Removes the special casing for foldl

Has to implement both functions as arguments and type
place holders (variables) for type constructors.

TODO.md

@@ -11,28 +11,22 @@
 - Implement a FizzBuzz example
 - Also, check the codes for FIXME and TODO
 - Allocation is done using pointers for members, is this desired?
-- Functions don't seem to be a thing on typing level yet?
-- static_array and tuple should probably not be PrimitiveType3, but instead subclass AppliedType3?
 - See if we want to replace Fractional with Real, and add Rational, Irrationl, Algebraic, Transendental
+  - Implement q32? q64? Two i32/i64 divided?
 - Does Subscript do what we want? It's a language feature rather a normal typed thing. How would you implement your own Subscript-able type?
+  - Clean up Subscript implementation - it's half implemented in the compiler. Makes more sense to move more parts to stdlib_types.
 - Have a set of rules or guidelines for the constraint comments, they're messy.
+- Why is expression_subscript_bytes using a helper method but expression_subscript_static_array is not?
 
-- Find pytest.mark.skip
+- Parser is putting stuff in ModuleDataBlock
-- There's a weird resolve_as reference in calculate_alloc_size
+  - Surely the compiler should build data blocks
-  - Either there should be more of them or less
-  - At first glance, looks like failure in the typing system
-  - Related to the FIXME in phasm_type3?
-  - Related: Parser is putting stuff in ModuleDataBlock
-- Casting is not implemented except u32 which is special cased
 - Make prelude more an actual thing
-  - Merge in type3types.LOOKUP_TABLE
+  - Merge in compiler.INSTANCES
+  - Make it less build in - have a environment class of some kind
 - Implemented Bounded: https://hackage.haskell.org/package/base-4.21.0.0/docs/Prelude.html#t:Bounded
 - Try to implement the min and max functions using select
 - Filter out methods that aren't used; other the other way around (easier?) only add __ methods when needed
-- Move UnaryOp.operator into type class methods
 - Move foldr into type class methods
-- PrimitiveType is just the type, nothing primitive about it (change the name). u32 are still basic types or something.
+  - Functions don't seem to be a thing on typing level yet?
-- Clean up Subscript implementation - it's half implemented in the compiler. Makes more sense to move more parts to stdlib_types.
+  - Related to the FIXME in phasm_type3?
-- Type constuctor should also be able to constuct placeholders - somehow.
+  - Type constuctor should also be able to constuct placeholders - somehow.
-- Make struct a type constructor?
-- Add InternalPassAsPointer to Struct?

examples/crc32.py

@@ -51,7 +51,7 @@ _CRC32_Table: u32[256] = (
 )
 
 def _crc32_f(crc: u32, byt: u8) -> u32:
-    return (crc >> 8) ^ _CRC32_Table[(crc & 0xFF) ^ u32(byt)]
+    return (crc >> 8) ^ _CRC32_Table[(crc & 0xFF) ^ extend(byt)]
 
 @exported
 def crc32(data: bytes) -> u32:

phasm/codestyle.py

@@ -6,8 +6,7 @@ It's intented to be a "any color, as long as it's black" kind of renderer
 from typing import Generator
 
 from . import ourlang, prelude
-from .type3.placeholders import TYPE3_ASSERTION_ERROR, Type3OrPlaceholder
+from .type3.types import Type3, TypeApplication_Struct
-from .type3.types import Type3
 
 
 def phasm_render(inp: ourlang.Module) -> str:
@@ -18,12 +17,10 @@ def phasm_render(inp: ourlang.Module) -> str:
 
 Statements = Generator[str, None, None]
 
-def type3(inp: Type3OrPlaceholder) -> str:
+def type3(inp: Type3) -> str:
     """
     Render: type's name
     """
-    assert isinstance(inp, Type3), TYPE3_ASSERTION_ERROR
-
     if inp is prelude.none:
         return 'None'
 
@@ -33,11 +30,10 @@ def struct_definition(inp: ourlang.StructDefinition) -> str:
     """
     Render: TypeStruct's definition
     """
-    st_args = prelude.struct.did_construct(inp.struct_type3)
+    assert isinstance(inp.struct_type3.application, TypeApplication_Struct)
-    assert st_args is not None
 
     result = f'class {inp.struct_type3.name}:\n'
-    for mem, typ in st_args.items():
+    for mem, typ in inp.struct_type3.application.arguments:
         result += f'    {mem}: {type3(typ)}\n'
 
     return result
@@ -67,7 +63,7 @@ def expression(inp: ourlang.Expression) -> str:
         ) + ', )'
 
     if isinstance(inp, ourlang.ConstantStruct):
-        return inp.struct_name + '(' + ', '.join(
+        return inp.struct_type3.name + '(' + ', '.join(
             expression(x)
             for x in inp.value
         ) + ')'
@@ -75,16 +71,6 @@ def expression(inp: ourlang.Expression) -> str:
     if isinstance(inp, ourlang.VariableReference):
         return str(inp.variable.name)
 
-    if isinstance(inp, ourlang.UnaryOp):
-        if inp.operator == 'cast':
-            mtyp = type3(inp.type3)
-            if mtyp is None:
-                raise NotImplementedError(f'Casting to type {inp.type_var}')
-
-            return f'{mtyp}({expression(inp.right)})'
-
-        return f'{inp.operator}{expression(inp.right)}'
-
     if isinstance(inp, ourlang.BinaryOp):
         return f'{expression(inp.left)} {inp.operator.name} {expression(inp.right)}'
 
@@ -116,10 +102,6 @@ def expression(inp: ourlang.Expression) -> str:
     if isinstance(inp, ourlang.AccessStructMember):
         return f'{expression(inp.varref)}.{inp.member}'
 
-    if isinstance(inp, ourlang.Fold):
-        fold_name = 'foldl' if ourlang.Fold.Direction.LEFT == inp.dir else 'foldr'
-        return f'{fold_name}({inp.func.name}, {expression(inp.base)}, {expression(inp.iter)})'
-
     raise NotImplementedError(expression, inp)
 
 def statement(inp: ourlang.Statement) -> Statements:

phasm/compiler.py

@@ -2,18 +2,28 @@
 This module contains the code to convert parsed Ourlang into WebAssembly code
 """
 import struct
-from typing import Dict, List, Optional
+from typing import List, Optional
 
-from . import codestyle, ourlang, prelude, wasm
+from . import ourlang, prelude, wasm
 from .runtime import calculate_alloc_size, calculate_member_offset
 from .stdlib import alloc as stdlib_alloc
 from .stdlib import types as stdlib_types
-from .type3 import functions as type3functions
+from .type3.functions import TypeVariable
-from .type3 import placeholders as type3placeholders
+from .type3.routers import NoRouteForTypeException, TypeApplicationRouter
-from .type3 import typeclasses as type3classes
+from .type3.typeclasses import Type3ClassMethod
-from .type3 import types as type3types
+from .type3.types import (
+    IntType3,
+    Type3,
+    TypeApplication_Struct,
+    TypeApplication_TypeInt,
+    TypeApplication_TypeStar,
+    TypeConstructor_StaticArray,
+    TypeConstructor_Tuple,
+)
 from .wasmgenerator import Generator as WasmGenerator
 
+TYPE3_ASSERTION_ERROR = 'You must call phasm_type3 after calling phasm_parse before your program can be compiled'
+
 LOAD_STORE_TYPE_MAP = {
     'i8': 'i32', # Have to use an u32, since there is no native i8 type
     'u8': 'i32', # Have to use an u32, since there is no native u8 type
@@ -28,217 +38,6 @@ LOAD_STORE_TYPE_MAP = {
     'bytes': 'i32', # Bytes are passed around as pointers
 }
 
-# For now this is nice & clean, but this will get messy quick
-# Especially once we get functions with polymorphying applied types
-INSTANCES = {
-    prelude.Eq.operators['==']: {
-        'a=u8': stdlib_types.u8_eq_equals,
-        'a=u32': stdlib_types.u32_eq_equals,
-        'a=u64': stdlib_types.u64_eq_equals,
-        'a=i8': stdlib_types.i8_eq_equals,
-        'a=i32': stdlib_types.i32_eq_equals,
-        'a=i64': stdlib_types.i64_eq_equals,
-        'a=f32': stdlib_types.f32_eq_equals,
-        'a=f64': stdlib_types.f64_eq_equals,
-    },
-    prelude.Eq.operators['!=']: {
-        'a=u8': stdlib_types.u8_eq_not_equals,
-        'a=u32': stdlib_types.u32_eq_not_equals,
-        'a=u64': stdlib_types.u64_eq_not_equals,
-        'a=i8': stdlib_types.i8_eq_not_equals,
-        'a=i32': stdlib_types.i32_eq_not_equals,
-        'a=i64': stdlib_types.i64_eq_not_equals,
-        'a=f32': stdlib_types.f32_eq_not_equals,
-        'a=f64': stdlib_types.f64_eq_not_equals,
-    },
-    prelude.Ord.methods['min']: {
-        'a=u8': stdlib_types.u8_ord_min,
-        'a=u32': stdlib_types.u32_ord_min,
-        'a=u64': stdlib_types.u64_ord_min,
-        'a=i8': stdlib_types.i8_ord_min,
-        'a=i32': stdlib_types.i32_ord_min,
-        'a=i64': stdlib_types.i64_ord_min,
-        'a=f32': stdlib_types.f32_ord_min,
-        'a=f64': stdlib_types.f64_ord_min,
-    },
-    prelude.Ord.methods['max']: {
-        'a=u8': stdlib_types.u8_ord_max,
-        'a=u32': stdlib_types.u32_ord_max,
-        'a=u64': stdlib_types.u64_ord_max,
-        'a=i8': stdlib_types.i8_ord_max,
-        'a=i32': stdlib_types.i32_ord_max,
-        'a=i64': stdlib_types.i64_ord_max,
-        'a=f32': stdlib_types.f32_ord_max,
-        'a=f64': stdlib_types.f64_ord_max,
-    },
-    prelude.Ord.operators['<']: {
-        'a=u8': stdlib_types.u8_ord_less_than,
-        'a=u32': stdlib_types.u32_ord_less_than,
-        'a=u64': stdlib_types.u64_ord_less_than,
-        'a=i8': stdlib_types.i8_ord_less_than,
-        'a=i32': stdlib_types.i32_ord_less_than,
-        'a=i64': stdlib_types.i64_ord_less_than,
-        'a=f32': stdlib_types.f32_ord_less_than,
-        'a=f64': stdlib_types.f64_ord_less_than,
-    },
-    prelude.Ord.operators['<=']: {
-        'a=u8': stdlib_types.u8_ord_less_than_or_equal,
-        'a=u32': stdlib_types.u32_ord_less_than_or_equal,
-        'a=u64': stdlib_types.u64_ord_less_than_or_equal,
-        'a=i8': stdlib_types.i8_ord_less_than_or_equal,
-        'a=i32': stdlib_types.i32_ord_less_than_or_equal,
-        'a=i64': stdlib_types.i64_ord_less_than_or_equal,
-        'a=f32': stdlib_types.f32_ord_less_than_or_equal,
-        'a=f64': stdlib_types.f64_ord_less_than_or_equal,
-    },
-    prelude.Ord.operators['>']: {
-        'a=u8': stdlib_types.u8_ord_greater_than,
-        'a=u32': stdlib_types.u32_ord_greater_than,
-        'a=u64': stdlib_types.u64_ord_greater_than,
-        'a=i8': stdlib_types.i8_ord_greater_than,
-        'a=i32': stdlib_types.i32_ord_greater_than,
-        'a=i64': stdlib_types.i64_ord_greater_than,
-        'a=f32': stdlib_types.f32_ord_greater_than,
-        'a=f64': stdlib_types.f64_ord_greater_than,
-    },
-    prelude.Ord.operators['>=']: {
-        'a=u8': stdlib_types.u8_ord_greater_than_or_equal,
-        'a=u32': stdlib_types.u32_ord_greater_than_or_equal,
-        'a=u64': stdlib_types.u64_ord_greater_than_or_equal,
-        'a=i8': stdlib_types.i8_ord_greater_than_or_equal,
-        'a=i32': stdlib_types.i32_ord_greater_than_or_equal,
-        'a=i64': stdlib_types.i64_ord_greater_than_or_equal,
-        'a=f32': stdlib_types.f32_ord_greater_than_or_equal,
-        'a=f64': stdlib_types.f64_ord_greater_than_or_equal,
-    },
-    prelude.Bits.methods['shl']: {
-        'a=u8': stdlib_types.u8_bits_logical_shift_left,
-        'a=u32': stdlib_types.u32_bits_logical_shift_left,
-        'a=u64': stdlib_types.u64_bits_logical_shift_left,
-    },
-    prelude.Bits.methods['shr']: {
-        'a=u8': stdlib_types.u8_bits_logical_shift_right,
-        'a=u32': stdlib_types.u32_bits_logical_shift_right,
-        'a=u64': stdlib_types.u64_bits_logical_shift_right,
-    },
-    prelude.Bits.methods['rotl']: {
-        'a=u8': stdlib_types.u8_bits_rotate_left,
-        'a=u32': stdlib_types.u32_bits_rotate_left,
-        'a=u64': stdlib_types.u64_bits_rotate_left,
-    },
-    prelude.Bits.methods['rotr']: {
-        'a=u8': stdlib_types.u8_bits_rotate_right,
-        'a=u32': stdlib_types.u32_bits_rotate_right,
-        'a=u64': stdlib_types.u64_bits_rotate_right,
-    },
-    prelude.Bits.operators['&']: {
-        'a=u8': stdlib_types.u8_bits_bitwise_and,
-        'a=u32': stdlib_types.u32_bits_bitwise_and,
-        'a=u64': stdlib_types.u64_bits_bitwise_and,
-    },
-    prelude.Bits.operators['|']: {
-        'a=u8': stdlib_types.u8_bits_bitwise_or,
-        'a=u32': stdlib_types.u32_bits_bitwise_or,
-        'a=u64': stdlib_types.u64_bits_bitwise_or,
-    },
-    prelude.Bits.operators['^']: {
-        'a=u8': stdlib_types.u8_bits_bitwise_xor,
-        'a=u32': stdlib_types.u32_bits_bitwise_xor,
-        'a=u64': stdlib_types.u64_bits_bitwise_xor,
-    },
-    prelude.Floating.methods['sqrt']: {
-        'a=f32': stdlib_types.f32_floating_sqrt,
-        'a=f64': stdlib_types.f64_floating_sqrt,
-    },
-    prelude.Fractional.methods['ceil']: {
-        'a=f32': stdlib_types.f32_fractional_ceil,
-        'a=f64': stdlib_types.f64_fractional_ceil,
-    },
-    prelude.Fractional.methods['floor']: {
-        'a=f32': stdlib_types.f32_fractional_floor,
-        'a=f64': stdlib_types.f64_fractional_floor,
-    },
-    prelude.Fractional.methods['trunc']: {
-        'a=f32': stdlib_types.f32_fractional_trunc,
-        'a=f64': stdlib_types.f64_fractional_trunc,
-    },
-    prelude.Fractional.methods['nearest']: {
-        'a=f32': stdlib_types.f32_fractional_nearest,
-        'a=f64': stdlib_types.f64_fractional_nearest,
-    },
-    prelude.Fractional.operators['/']: {
-        'a=f32': stdlib_types.f32_fractional_div,
-        'a=f64': stdlib_types.f64_fractional_div,
-    },
-    prelude.Integral.operators['//']: {
-        'a=u32': stdlib_types.u32_integral_div,
-        'a=u64': stdlib_types.u64_integral_div,
-        'a=i32': stdlib_types.i32_integral_div,
-        'a=i64': stdlib_types.i64_integral_div,
-    },
-    prelude.Integral.operators['%']: {
-        'a=u32': stdlib_types.u32_integral_rem,
-        'a=u64': stdlib_types.u64_integral_rem,
-        'a=i32': stdlib_types.i32_integral_rem,
-        'a=i64': stdlib_types.i64_integral_rem,
-    },
-    prelude.IntNum.methods['abs']: {
-        'a=i32': stdlib_types.i32_intnum_abs,
-        'a=i64': stdlib_types.i64_intnum_abs,
-        'a=f32': stdlib_types.f32_intnum_abs,
-        'a=f64': stdlib_types.f64_intnum_abs,
-    },
-    prelude.IntNum.methods['neg']: {
-        'a=i32': stdlib_types.i32_intnum_neg,
-        'a=i64': stdlib_types.i64_intnum_neg,
-        'a=f32': stdlib_types.f32_intnum_neg,
-        'a=f64': stdlib_types.f64_intnum_neg,
-    },
-    prelude.NatNum.operators['+']: {
-        'a=u32': stdlib_types.u32_natnum_add,
-        'a=u64': stdlib_types.u64_natnum_add,
-        'a=i32': stdlib_types.i32_natnum_add,
-        'a=i64': stdlib_types.i64_natnum_add,
-        'a=f32': stdlib_types.f32_natnum_add,
-        'a=f64': stdlib_types.f64_natnum_add,
-    },
-    prelude.NatNum.operators['-']: {
-        'a=u32': stdlib_types.u32_natnum_sub,
-        'a=u64': stdlib_types.u64_natnum_sub,
-        'a=i32': stdlib_types.i32_natnum_sub,
-        'a=i64': stdlib_types.i64_natnum_sub,
-        'a=f32': stdlib_types.f32_natnum_sub,
-        'a=f64': stdlib_types.f64_natnum_sub,
-    },
-    prelude.NatNum.operators['*']: {
-        'a=u32': stdlib_types.u32_natnum_mul,
-        'a=u64': stdlib_types.u64_natnum_mul,
-        'a=i32': stdlib_types.i32_natnum_mul,
-        'a=i64': stdlib_types.i64_natnum_mul,
-        'a=f32': stdlib_types.f32_natnum_mul,
-        'a=f64': stdlib_types.f64_natnum_mul,
-    },
-    prelude.NatNum.operators['<<']: {
-        'a=u32': stdlib_types.u32_natnum_arithmic_shift_left,
-        'a=u64': stdlib_types.u64_natnum_arithmic_shift_left,
-        'a=i32': stdlib_types.i32_natnum_arithmic_shift_left,
-        'a=i64': stdlib_types.i64_natnum_arithmic_shift_left,
-        'a=f32': stdlib_types.f32_natnum_arithmic_shift_left,
-        'a=f64': stdlib_types.f64_natnum_arithmic_shift_left,
-    },
-    prelude.NatNum.operators['>>']: {
-        'a=u32': stdlib_types.u32_natnum_arithmic_shift_right,
-        'a=u64': stdlib_types.u64_natnum_arithmic_shift_right,
-        'a=i32': stdlib_types.i32_natnum_arithmic_shift_right,
-        'a=i64': stdlib_types.i64_natnum_arithmic_shift_right,
-        'a=f32': stdlib_types.f32_natnum_arithmic_shift_right,
-        'a=f64': stdlib_types.f64_natnum_arithmic_shift_right,
-    },
-    prelude.Sized_.methods['len']: {
-        'a=bytes': stdlib_types.bytes_sized_len,
-    },
-}
-
 def phasm_compile(inp: ourlang.Module) -> wasm.Module:
     """
     Public method for compiling a parsed Phasm module into
@@ -246,14 +45,14 @@ def phasm_compile(inp: ourlang.Module) -> wasm.Module:
     """
     return module(inp)
 
-def type3(inp: type3placeholders.Type3OrPlaceholder) -> wasm.WasmType:
+def type3(inp: Type3) -> wasm.WasmType:
     """
     Compile: type
 
     Types are used for example in WebAssembly function parameters
     and return types.
     """
-    assert isinstance(inp, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
+    assert inp is not None, TYPE3_ASSERTION_ERROR
 
     if inp == prelude.none:
         return wasm.WasmTypeNone()
@@ -296,7 +95,7 @@ def type3(inp: type3placeholders.Type3OrPlaceholder) -> wasm.WasmType:
         # And pointers are i32
         return wasm.WasmTypeInt32()
 
-    if prelude.InternalPassAsPointer in inp.classes:
+    if (prelude.InternalPassAsPointer, (inp, )) in prelude.PRELUDE_TYPE_CLASS_INSTANCES_EXISTING:
         return wasm.WasmTypeInt32()
 
     raise NotImplementedError(type3, inp)
@@ -305,25 +104,30 @@ def tuple_instantiation(wgn: WasmGenerator, inp: ourlang.TupleInstantiation) ->
     """
     Compile: Instantiation (allocation) of a tuple
     """
-    assert isinstance(inp.type3, type3types.Type3)
+    assert inp.type3 is not None, TYPE3_ASSERTION_ERROR
 
-    args: list[type3types.Type3] = []
+    args: tuple[Type3, ...]
 
-    sa_args = prelude.static_array.did_construct(inp.type3)
+    if isinstance(inp.type3.application, TypeApplication_TypeStar):
-    if sa_args is not None:
+        # Possibly paranoid assert. If we have a future variadic type,
-        sa_type, sa_len = sa_args
+        # does it also do this tuple instantation like this?
-        args = [sa_type for _ in range(sa_len.value)]
+        assert isinstance(inp.type3.application.constructor, TypeConstructor_Tuple)
 
-    if not args:
+        args = inp.type3.application.arguments
-        tp_args = prelude.tuple_.did_construct(inp.type3)
+    elif isinstance(inp.type3.application, TypeApplication_TypeInt):
-        if tp_args is None:
+        # Possibly paranoid assert. If we have a future type of kind * -> Int -> *,
-            raise NotImplementedError
+        # does it also do this tuple instantation like this?
+        assert isinstance(inp.type3.application.constructor, TypeConstructor_StaticArray)
 
-        args = list(tp_args)
+        sa_type, sa_len = inp.type3.application.arguments
+
+        args = tuple(sa_type for _ in range(sa_len.value))
+    else:
+        raise NotImplementedError('tuple_instantiation', inp.type3)
 
     comment_elements = ''
     for element in inp.elements:
-        assert isinstance(element.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
+        assert element.type3 is not None, TYPE3_ASSERTION_ERROR
         comment_elements += f'{element.type3.name}, '
 
     tmp_var = wgn.temp_var_i32('tuple_adr')
@@ -337,17 +141,11 @@ def tuple_instantiation(wgn: WasmGenerator, inp: ourlang.TupleInstantiation) ->
     # Store each element individually
     offset = 0
     for element, exp_type3 in zip(inp.elements, args, strict=True):
-        if isinstance(exp_type3, type3placeholders.PlaceholderForType):
-            assert exp_type3.resolve_as is not None
-            assert isinstance(exp_type3.resolve_as, type3types.Type3)
-            exp_type3 = exp_type3.resolve_as
-
         assert element.type3 == exp_type3
 
-        if prelude.InternalPassAsPointer in exp_type3.classes:
+        if (prelude.InternalPassAsPointer, (exp_type3, )) in prelude.PRELUDE_TYPE_CLASS_INSTANCES_EXISTING:
             mtyp = 'i32'
         else:
-            assert isinstance(exp_type3, type3types.Type3), NotImplementedError('Tuple of applied types / structs')
             mtyp = LOAD_STORE_TYPE_MAP[exp_type3.name]
 
         wgn.add_statement('nop', comment='PRE')
@@ -361,6 +159,78 @@ def tuple_instantiation(wgn: WasmGenerator, inp: ourlang.TupleInstantiation) ->
     # Return the allocated address
     wgn.local.get(tmp_var)
 
+def expression_subscript_bytes(
+        attrs: tuple[WasmGenerator, ourlang.Subscript],
+    ) -> None:
+    wgn, inp = attrs
+
+    expression(wgn, inp.varref)
+    expression(wgn, inp.index)
+    wgn.call(stdlib_types.__subscript_bytes__)
+
+def expression_subscript_static_array(
+        attrs: tuple[WasmGenerator, ourlang.Subscript],
+        args: tuple[Type3, IntType3],
+    ) -> None:
+    wgn, inp = attrs
+
+    el_type, el_len = args
+
+    # OPTIMIZE: If index is a constant, we can use offset instead of multiply
+    # and we don't need to do the out of bounds check
+
+    expression(wgn, inp.varref)
+
+    tmp_var = wgn.temp_var_i32('index')
+    expression(wgn, inp.index)
+    wgn.local.tee(tmp_var)
+
+    # Out of bounds check based on el_len.value
+    wgn.i32.const(el_len.value)
+    wgn.i32.ge_u()
+    with wgn.if_():
+        wgn.unreachable(comment='Out of bounds')
+
+    wgn.local.get(tmp_var)
+    wgn.i32.const(calculate_alloc_size(el_type))
+    wgn.i32.mul()
+    wgn.i32.add()
+
+    mtyp = LOAD_STORE_TYPE_MAP[el_type.name]
+
+    wgn.add_statement(f'{mtyp}.load')
+
+def expression_subscript_tuple(
+        attrs: tuple[WasmGenerator, ourlang.Subscript],
+        args: tuple[Type3, ...],
+    ) -> None:
+    wgn, inp = attrs
+
+    assert isinstance(inp.index, ourlang.ConstantPrimitive)
+    assert isinstance(inp.index.value, int)
+
+    offset = 0
+    for el_type in args[0:inp.index.value]:
+        assert el_type is not None, TYPE3_ASSERTION_ERROR
+        offset += calculate_alloc_size(el_type)
+
+    el_type = args[inp.index.value]
+    assert el_type is not None, TYPE3_ASSERTION_ERROR
+
+    expression(wgn, inp.varref)
+
+    if (prelude.InternalPassAsPointer, (el_type, )) in prelude.PRELUDE_TYPE_CLASS_INSTANCES_EXISTING:
+        mtyp = 'i32'
+    else:
+        mtyp = LOAD_STORE_TYPE_MAP[el_type.name]
+
+    wgn.add_statement(f'{mtyp}.load', f'offset={offset}')
+
+SUBSCRIPT_ROUTER = TypeApplicationRouter[tuple[WasmGenerator, ourlang.Subscript], None]()
+SUBSCRIPT_ROUTER.add_n(prelude.bytes_, expression_subscript_bytes)
+SUBSCRIPT_ROUTER.add(prelude.static_array, expression_subscript_static_array)
+SUBSCRIPT_ROUTER.add(prelude.tuple_, expression_subscript_tuple)
+
 def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
     """
     Compile: Any expression
@@ -370,7 +240,7 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
         raise Exception
 
     if isinstance(inp, ourlang.ConstantPrimitive):
-        assert isinstance(inp.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
+        assert inp.type3 is not None, TYPE3_ASSERTION_ERROR
 
         if inp.type3 in (prelude.i8, prelude.u8, ):
             # No native u8 type - treat as i32, with caution
@@ -411,9 +281,9 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
             return
 
         if isinstance(inp.variable, ourlang.ModuleConstantDef):
-            assert isinstance(inp.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
+            assert inp.type3 is not None, TYPE3_ASSERTION_ERROR
 
-            if prelude.InternalPassAsPointer in inp.type3.classes:
+            if (prelude.InternalPassAsPointer, (inp.type3, )) in prelude.PRELUDE_TYPE_CLASS_INSTANCES_EXISTING:
                 assert isinstance(inp.variable.constant, (ourlang.ConstantBytes, ourlang.ConstantStruct, ourlang.ConstantTuple, ))
 
                 address = inp.variable.constant.data_block.address
@@ -421,11 +291,8 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
                 wgn.i32.const(address)
                 return
 
-            if isinstance(inp.type3, type3types.Type3):
+            expression(wgn, inp.variable.constant)
-                expression(wgn, inp.variable.constant)
+            return
-                return
-
-            raise NotImplementedError(expression, inp)
 
         raise NotImplementedError(expression, inp.variable)
 
@@ -433,69 +300,52 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
         expression(wgn, inp.left)
         expression(wgn, inp.right)
 
-        assert isinstance(inp.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
+        type_var_map: dict[TypeVariable, Type3] = {}
-
-        type_var_map: Dict[type3functions.TypeVariable, type3types.Type3] = {}
 
         for type_var, arg_expr in zip(inp.operator.signature.args, [inp.left, inp.right, inp], strict=True):
-            if not isinstance(type_var, type3functions.TypeVariable):
+            assert arg_expr.type3 is not None, TYPE3_ASSERTION_ERROR
+
+            if isinstance(type_var, Type3):
                 # Fixed type, not part of the lookup requirements
                 continue
 
-            assert isinstance(arg_expr.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
+            if isinstance(type_var, TypeVariable):
-            type_var_map[type_var] = arg_expr.type3
+                type_var_map[type_var] = arg_expr.type3
+                continue
 
-        instance_key = ','.join(
+            raise NotImplementedError(type_var, arg_expr.type3)
-            f'{k.letter}={v.name}'
-            for k, v in type_var_map.items()
-        )
 
-        instance = INSTANCES.get(inp.operator, {}).get(instance_key, None)
+        router = prelude.PRELUDE_TYPE_CLASS_INSTANCE_METHODS[inp.operator]
-        if instance is not None:
+        router(wgn, type_var_map)
-            instance(wgn)
+        return
-            return
-
-        raise NotImplementedError(inp.operator, instance_key)
-
-    if isinstance(inp, ourlang.UnaryOp):
-        expression(wgn, inp.right)
-
-        assert isinstance(inp.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
-
-        if inp.operator == 'cast':
-            if inp.type3 == prelude.u32 and inp.right.type3 == prelude.u8:
-                # Nothing to do, you can use an u8 value as a u32 no problem
-                return
-
-        raise NotImplementedError(expression, inp.type3, inp.operator)
 
     if isinstance(inp, ourlang.FunctionCall):
         for arg in inp.arguments:
             expression(wgn, arg)
 
-        if isinstance(inp.function, type3classes.Type3ClassMethod):
+        if isinstance(inp.function, Type3ClassMethod):
             # FIXME: Duplicate code with BinaryOp
             type_var_map = {}
 
             for type_var, arg_expr in zip(inp.function.signature.args, inp.arguments + [inp], strict=True):
-                if not isinstance(type_var, type3functions.TypeVariable):
+                assert arg_expr.type3 is not None, TYPE3_ASSERTION_ERROR
+
+                if isinstance(type_var, Type3):
                     # Fixed type, not part of the lookup requirements
                     continue
 
-                assert isinstance(arg_expr.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
+                if isinstance(type_var, TypeVariable):
-                type_var_map[type_var] = arg_expr.type3
+                    type_var_map[type_var] = arg_expr.type3
+                    continue
 
-            instance_key = ','.join(
+                raise NotImplementedError(type_var, arg_expr.type3)
-                f'{k.letter}={v.name}'
-                for k, v in type_var_map.items()
-            )
 
-            instance = INSTANCES.get(inp.function, {}).get(instance_key, None)
+            router = prelude.PRELUDE_TYPE_CLASS_INSTANCE_METHODS[inp.function]
-            if instance is not None:
+            try:
-                instance(wgn)
+                router(wgn, type_var_map)
-                return
+            except NoRouteForTypeException:
-
+                raise NotImplementedError(str(inp.function), type_var_map)
-            raise NotImplementedError(inp.function, instance_key)
+            return
 
         wgn.add_statement('call', '${}'.format(inp.function.name))
         return
@@ -505,173 +355,29 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
         return
 
     if isinstance(inp, ourlang.Subscript):
-        assert isinstance(inp.varref.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
+        assert inp.varref.type3 is not None, TYPE3_ASSERTION_ERROR
 
-        if inp.varref.type3 is prelude.bytes_:
+        # Type checker guarantees we don't get routing errors
-            expression(wgn, inp.varref)
+        SUBSCRIPT_ROUTER((wgn, inp, ), inp.varref.type3)
-            expression(wgn, inp.index)
+        return
-            wgn.call(stdlib_types.__subscript_bytes__)
-            return
-
-        assert isinstance(inp.varref.type3, type3types.Type3)
-
-        sa_args = prelude.static_array.did_construct(inp.varref.type3)
-        if sa_args is not None:
-                el_type, el_len = sa_args
-
-                # OPTIMIZE: If index is a constant, we can use offset instead of multiply
-                # and we don't need to do the out of bounds check
-
-                expression(wgn, inp.varref)
-
-                tmp_var = wgn.temp_var_i32('index')
-                expression(wgn, inp.index)
-                wgn.local.tee(tmp_var)
-
-                # Out of bounds check based on el_len.value
-                wgn.i32.const(el_len.value)
-                wgn.i32.ge_u()
-                with wgn.if_():
-                    wgn.unreachable(comment='Out of bounds')
-
-                wgn.local.get(tmp_var)
-                wgn.i32.const(calculate_alloc_size(el_type))
-                wgn.i32.mul()
-                wgn.i32.add()
-
-                assert isinstance(el_type, type3types.Type3), NotImplementedError('Tuple of applied types / structs')
-                mtyp = LOAD_STORE_TYPE_MAP[el_type.name]
-
-                wgn.add_statement(f'{mtyp}.load')
-                return
-
-        tp_args = prelude.tuple_.did_construct(inp.varref.type3)
-        if tp_args is not None:
-                assert isinstance(inp.index, ourlang.ConstantPrimitive)
-                assert isinstance(inp.index.value, int)
-
-                offset = 0
-                for el_type in tp_args[0:inp.index.value]:
-                    assert isinstance(el_type, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
-                    offset += calculate_alloc_size(el_type)
-
-                el_type = tp_args[inp.index.value]
-                assert isinstance(el_type, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
-
-                expression(wgn, inp.varref)
-
-                if prelude.InternalPassAsPointer in el_type.classes:
-                    mtyp = 'i32'
-                else:
-                    assert isinstance(el_type, type3types.Type3), NotImplementedError('Tuple of applied types / structs')
-                    mtyp = LOAD_STORE_TYPE_MAP[el_type.name]
-
-                wgn.add_statement(f'{mtyp}.load', f'offset={offset}')
-                return
-
-        raise NotImplementedError(expression, inp, inp.varref.type3)
 
     if isinstance(inp, ourlang.AccessStructMember):
-        assert isinstance(inp.struct_type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
+        assert inp.struct_type3 is not None, TYPE3_ASSERTION_ERROR
 
-        st_args = prelude.struct.did_construct(inp.struct_type3)
+        assert isinstance(inp.struct_type3.application, TypeApplication_Struct)
-        assert st_args is not None
 
-        member_type = st_args[inp.member]
+        member_type = dict(inp.struct_type3.application.arguments)[inp.member]
 
-        assert isinstance(member_type, type3types.Type3), NotImplementedError('Tuple of applied types / structs')
         mtyp = LOAD_STORE_TYPE_MAP[member_type.name]
 
         expression(wgn, inp.varref)
         wgn.add_statement(f'{mtyp}.load', 'offset=' + str(calculate_member_offset(
-            inp.struct_type3.name, st_args, inp.member
+            inp.struct_type3.name, inp.struct_type3.application.arguments, inp.member
         )))
         return
 
-    if isinstance(inp, ourlang.Fold):
-        expression_fold(wgn, inp)
-        return
-
     raise NotImplementedError(expression, inp)
 
-def expression_fold(wgn: WasmGenerator, inp: ourlang.Fold) -> None:
-    """
-    Compile: Fold expression
-    """
-    assert isinstance(inp.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
-
-    if inp.iter.type3 is not prelude.bytes_:
-        raise NotImplementedError(expression_fold, inp, inp.iter.type3)
-
-    wgn.add_statement('nop', comment='acu :: u8')
-    acu_var = wgn.temp_var_u8(f'fold_{codestyle.type3(inp.type3)}_acu')
-    wgn.add_statement('nop', comment='adr :: bytes*')
-    adr_var = wgn.temp_var_i32('fold_i32_adr')
-    wgn.add_statement('nop', comment='len :: i32')
-    len_var = wgn.temp_var_i32('fold_i32_len')
-
-    wgn.add_statement('nop', comment='acu = base')
-    expression(wgn, inp.base)
-    wgn.local.set(acu_var)
-
-    wgn.add_statement('nop', comment='adr = adr(iter)')
-    expression(wgn, inp.iter)
-    wgn.local.set(adr_var)
-
-    wgn.add_statement('nop', comment='len = len(iter)')
-    wgn.local.get(adr_var)
-    wgn.i32.load()
-    wgn.local.set(len_var)
-
-    wgn.add_statement('nop', comment='i = 0')
-    idx_var = wgn.temp_var_i32(f'fold_{codestyle.type3(inp.type3)}_idx')
-    wgn.i32.const(0)
-    wgn.local.set(idx_var)
-
-    wgn.add_statement('nop', comment='if i < len')
-    wgn.local.get(idx_var)
-    wgn.local.get(len_var)
-    wgn.i32.lt_u()
-    with wgn.if_():
-        # From here on, adr_var is the address of byte we're referencing
-        # This is akin to calling stdlib_types.__subscript_bytes__
-        # But since we already know we are inside of bounds,
-        # can just bypass it and load the memory directly.
-        wgn.local.get(adr_var)
-        wgn.i32.const(3) # Bytes header -1, since we do a +1 every loop
-        wgn.i32.add()
-        wgn.local.set(adr_var)
-
-        wgn.add_statement('nop', comment='while True')
-        with wgn.loop():
-            wgn.add_statement('nop', comment='acu = func(acu, iter[i])')
-            wgn.local.get(acu_var)
-
-            # Get the next byte, write back the address
-            wgn.local.get(adr_var)
-            wgn.i32.const(1)
-            wgn.i32.add()
-            wgn.local.tee(adr_var)
-            wgn.i32.load8_u()
-
-            wgn.add_statement('call', f'${inp.func.name}')
-            wgn.local.set(acu_var)
-
-            wgn.add_statement('nop', comment='i = i + 1')
-            wgn.local.get(idx_var)
-            wgn.i32.const(1)
-            wgn.i32.add()
-            wgn.local.set(idx_var)
-
-            wgn.add_statement('nop', comment='if i >= len: break')
-            wgn.local.get(idx_var)
-            wgn.local.get(len_var)
-            wgn.i32.lt_u()
-            wgn.br_if(0)
-
-    # return acu
-    wgn.local.get(acu_var)
-
 def statement_return(wgn: WasmGenerator, inp: ourlang.StatementReturn) -> None:
     """
     Compile: Return statement
@@ -829,7 +535,7 @@ def module_data(inp: ourlang.ModuleData) -> bytes:
         data_list: List[bytes] = []
 
         for constant in block.data:
-            assert isinstance(constant.type3, type3types.Type3), (id(constant), type3placeholders.TYPE3_ASSERTION_ERROR)
+            assert constant.type3 is not None, TYPE3_ASSERTION_ERROR
 
             if isinstance(constant, ourlang.ConstantMemoryStored) and block is not constant.data_block:
                 # It's stored in a different block
@@ -959,8 +665,9 @@ def module(inp: ourlang.Module) -> wasm.Module:
     return result
 
 def _generate_struct_constructor(wgn: WasmGenerator, inp: ourlang.StructConstructor) -> None:
-    st_args = prelude.struct.did_construct(inp.struct_type3)
+    assert isinstance(inp.struct_type3.application, TypeApplication_Struct)
-    assert st_args is not None
+
+    st_args = inp.struct_type3.application.arguments
 
     tmp_var = wgn.temp_var_i32('struct_adr')
 
@@ -970,9 +677,9 @@ def _generate_struct_constructor(wgn: WasmGenerator, inp: ourlang.StructConstruc
     wgn.local.set(tmp_var)
 
     # Store each member individually
-    for memname, mtyp3 in st_args.items():
+    for memname, mtyp3 in st_args:
         mtyp: Optional[str]
-        if prelude.InternalPassAsPointer in mtyp3.classes:
+        if (prelude.InternalPassAsPointer, (mtyp3, )) in prelude.PRELUDE_TYPE_CLASS_INSTANCES_EXISTING:
             mtyp = 'i32'
         else:
             mtyp = LOAD_STORE_TYPE_MAP.get(mtyp3.name)

phasm/ourlang.py

@@ -1,14 +1,12 @@
 """
 Contains the syntax tree for ourlang
 """
-import enum
 from typing import Dict, Iterable, List, Optional, Union
 
 from . import prelude
 from .type3.functions import FunctionSignature, TypeVariableContext
-from .type3.placeholders import PlaceholderForType, Type3OrPlaceholder
 from .type3.typeclasses import Type3ClassMethod
-from .type3.types import Type3
+from .type3.types import Type3, TypeApplication_Struct
 
 
 class Expression:
@@ -17,10 +15,10 @@ class Expression:
     """
     __slots__ = ('type3', )
 
-    type3: Type3OrPlaceholder
+    type3: Type3 | None
 
     def __init__(self) -> None:
-        self.type3 = PlaceholderForType([self])
+        self.type3 = None
 
 class Constant(Expression):
     """
@@ -99,21 +97,21 @@ class ConstantStruct(ConstantMemoryStored):
     """
     A Struct constant value expression within a statement
     """
-    __slots__ = ('struct_name', 'value', )
+    __slots__ = ('struct_type3', 'value', )
 
-    struct_name: str
+    struct_type3: Type3
     value: List[Union[ConstantPrimitive, ConstantBytes, ConstantTuple, 'ConstantStruct']]
 
-    def __init__(self, struct_name: str, value: List[Union[ConstantPrimitive, ConstantBytes, ConstantTuple, 'ConstantStruct']], data_block: 'ModuleDataBlock') -> None:
+    def __init__(self, struct_type3: Type3, value: List[Union[ConstantPrimitive, ConstantBytes, ConstantTuple, 'ConstantStruct']], data_block: 'ModuleDataBlock') -> None:
         super().__init__(data_block)
-        self.struct_name = struct_name
+        self.struct_type3 = struct_type3
         self.value = value
 
     def __repr__(self) -> str:
         # Do not repr the whole ModuleDataBlock
         # As this has a reference back to this constant for its data
         # which it needs to compile the data into the program
-        return f'ConstantStruct({repr(self.struct_name)}, {repr(self.value)}, @{repr(self.data_block.address)})'
+        return f'ConstantStruct({self.struct_type3!r}, {self.value!r}, @{self.data_block.address!r})'
 
 class VariableReference(Expression):
     """
@@ -127,21 +125,6 @@ class VariableReference(Expression):
         super().__init__()
         self.variable = variable
 
-class UnaryOp(Expression):
-    """
-    A unary operator expression within a statement
-    """
-    __slots__ = ('operator', 'right', )
-
-    operator: str
-    right: Expression
-
-    def __init__(self, operator: str, right: Expression) -> None:
-        super().__init__()
-
-        self.operator = operator
-        self.right = right
-
 class BinaryOp(Expression):
     """
     A binary operator expression within a statement
@@ -213,46 +196,16 @@ class AccessStructMember(Expression):
     __slots__ = ('varref', 'struct_type3', 'member', )
 
     varref: VariableReference
-    struct_type3: Type3OrPlaceholder
+    struct_type3: Type3
     member: str
 
-    def __init__(self, varref: VariableReference,  struct_type3: Type3OrPlaceholder, member: str) -> None:
+    def __init__(self, varref: VariableReference,  struct_type3: Type3, member: str) -> None:
         super().__init__()
 
         self.varref = varref
         self.struct_type3 = struct_type3
         self.member = member
 
-class Fold(Expression):
-    """
-    A (left or right) fold
-    """
-    class Direction(enum.Enum):
-        """
-        Which direction to fold in
-        """
-        LEFT = 0
-        RIGHT = 1
-
-    dir: Direction
-    func: 'Function'
-    base: Expression
-    iter: Expression
-
-    def __init__(
-            self,
-            dir_: Direction,
-            func: 'Function',
-            base: Expression,
-            iter_: Expression,
-        ) -> None:
-        super().__init__()
-
-        self.dir = dir_
-        self.func = func
-        self.base = base
-        self.iter = iter_
-
 class Statement:
     """
     A statement within a function
@@ -299,7 +252,7 @@ class FunctionParam:
     __slots__ = ('name', 'type3', )
 
     name: str
-    type3: Type3OrPlaceholder
+    type3: Type3
 
     def __init__(self, name: str, type3: Type3) -> None:
         self.name = name
@@ -357,9 +310,9 @@ class StructConstructor(Function):
     def __init__(self, struct_type3: Type3) -> None:
         super().__init__(f'@{struct_type3.name}@__init___@', -1)
 
-        st_args = prelude.struct.did_construct(struct_type3)
+        assert isinstance(struct_type3.application, TypeApplication_Struct)
-        assert st_args is not None
+
-        for mem, typ in st_args.items():
+        for mem, typ in struct_type3.application.arguments:
             self.posonlyargs.append(FunctionParam(mem, typ, ))
             self.signature.args.append(typ)
 

phasm/parser.py

@@ -14,7 +14,6 @@ from .ourlang import (
     ConstantStruct,
     ConstantTuple,
     Expression,
-    Fold,
     Function,
     FunctionCall,
     FunctionParam,
@@ -29,12 +28,11 @@ from .ourlang import (
     StructDefinition,
     Subscript,
     TupleInstantiation,
-    UnaryOp,
     VariableReference,
 )
 from .prelude import PRELUDE_METHODS, PRELUDE_OPERATORS, PRELUDE_TYPES
-from .type3 import typeclasses as type3typeclasses
+from .type3.typeclasses import Type3ClassMethod
-from .type3 import types as type3types
+from .type3.types import IntType3, Type3
 
 
 def phasm_parse(source: str) -> Module:
@@ -164,8 +162,8 @@ class OurVisitor:
 
             arg_type = self.visit_type(module, arg.annotation)
 
-            # if isisntance(arg_type, TypeVariable):
+            # FIXME: Allow TypeVariable in the function signature
-            #   arg_type = PlaceHolderForType()
+            # This would also require FunctionParam to accept a placeholder
 
             function.signature.args.append(arg_type)
             function.posonlyargs.append(FunctionParam(
@@ -227,7 +225,7 @@ class OurVisitor:
         _not_implemented(not node.keywords, 'ClassDef.keywords')
         _not_implemented(not node.decorator_list, 'ClassDef.decorator_list')
 
-        members: Dict[str, type3types.Type3] = {}
+        members: Dict[str, Type3] = {}
 
         for stmt in node.body:
             if not isinstance(stmt, ast.AnnAssign):
@@ -247,7 +245,7 @@ class OurVisitor:
 
             members[stmt.target.id] = self.visit_type(module, stmt.annotation)
 
-        return StructDefinition(prelude.struct(node.name, members, set()), node.lineno)
+        return StructDefinition(prelude.struct(node.name, tuple(members.items())), node.lineno)
 
     def pre_visit_Module_AnnAssign(self, module: Module, node: ast.AnnAssign) -> ModuleConstantDef:
         if not isinstance(node.target, ast.Name):
@@ -353,7 +351,7 @@ class OurVisitor:
 
     def visit_Module_FunctionDef_expr(self, module: Module, function: Function, our_locals: OurLocals, node: ast.expr) -> Expression:
         if isinstance(node, ast.BinOp):
-            operator: Union[str, type3typeclasses.Type3ClassMethod]
+            operator: Union[str, Type3ClassMethod]
 
             if isinstance(node.op, ast.Add):
                 operator = '+'
@@ -389,19 +387,6 @@ class OurVisitor:
                 self.visit_Module_FunctionDef_expr(module, function, our_locals, node.right),
             )
 
-        if isinstance(node, ast.UnaryOp):
-            if isinstance(node.op, ast.UAdd):
-                operator = '+'
-            elif isinstance(node.op, ast.USub):
-                operator = '-'
-            else:
-                raise NotImplementedError(f'Operator {node.op}')
-
-            return UnaryOp(
-                operator,
-                self.visit_Module_FunctionDef_expr(module, function, our_locals, node.operand),
-            )
-
         if isinstance(node, ast.Compare):
             if 1 < len(node.ops):
                 raise NotImplementedError('Multiple operators')
@@ -476,7 +461,7 @@ class OurVisitor:
 
         raise NotImplementedError(f'{node} as expr in FunctionDef')
 
-    def visit_Module_FunctionDef_Call(self, module: Module, function: Function, our_locals: OurLocals, node: ast.Call) -> Union[Fold, FunctionCall, UnaryOp]:
+    def visit_Module_FunctionDef_Call(self, module: Module, function: Function, our_locals: OurLocals, node: ast.Call) -> Union[FunctionCall]:
         if node.keywords:
             _raise_static_error(node, 'Keyword calling not supported') # Yet?
 
@@ -485,42 +470,10 @@ class OurVisitor:
         if not isinstance(node.func.ctx, ast.Load):
             _raise_static_error(node, 'Must be load context')
 
-        func: Union[Function, type3typeclasses.Type3ClassMethod]
+        func: Union[Function, Type3ClassMethod]
 
         if node.func.id in PRELUDE_METHODS:
             func = PRELUDE_METHODS[node.func.id]
-        elif node.func.id == 'u32':
-            if 1 != len(node.args):
-                _raise_static_error(node, f'Function {node.func.id} requires 1 arguments but {len(node.args)} are given')
-
-            unary_op = UnaryOp(
-                'cast',
-                self.visit_Module_FunctionDef_expr(module, function, our_locals, node.args[0]),
-            )
-            unary_op.type3 = prelude.u32
-            return unary_op
-        elif node.func.id == 'foldl':
-            if 3 != len(node.args):
-                _raise_static_error(node, f'Function {node.func.id} requires 3 arguments but {len(node.args)} are given')
-
-            # TODO: This is not generic, you cannot return a function
-            subnode = node.args[0]
-            if not isinstance(subnode, ast.Name):
-                raise NotImplementedError(f'Calling methods that are not a name {subnode}')
-            if not isinstance(subnode.ctx, ast.Load):
-                _raise_static_error(subnode, 'Must be load context')
-            if subnode.id not in module.functions:
-                _raise_static_error(subnode, 'Reference to undefined function')
-            func = module.functions[subnode.id]
-            if 2 != len(func.posonlyargs):
-                _raise_static_error(node, f'Function {node.func.id} requires a function with 2 arguments but a function with {len(func.posonlyargs)} args is given')
-
-            return Fold(
-                Fold.Direction.LEFT,
-                func,
-                self.visit_Module_FunctionDef_expr(module, function, our_locals, node.args[1]),
-                self.visit_Module_FunctionDef_expr(module, function, our_locals, node.args[2]),
-            )
         else:
             if node.func.id not in module.functions:
                 _raise_static_error(node, 'Call to undefined function')
@@ -608,7 +561,8 @@ class OurVisitor:
             if not isinstance(node.func.ctx, ast.Load):
                 _raise_static_error(node.func, 'Must be load context')
 
-            if node.func.id not in module.struct_definitions:
+            struct_def = module.struct_definitions.get(node.func.id)
+            if struct_def is None:
                 _raise_static_error(node.func, 'Undefined struct')
 
             if node.keywords:
@@ -624,7 +578,7 @@ class OurVisitor:
 
             data_block = ModuleDataBlock(struct_data)
             module.data.blocks.append(data_block)
-            return ConstantStruct(node.func.id, struct_data, data_block)
+            return ConstantStruct(struct_def.struct_type3, struct_data, data_block)
 
         _not_implemented(node.kind is None, 'Constant.kind')
 
@@ -641,7 +595,7 @@ class OurVisitor:
 
         raise NotImplementedError(f'{node.value} as constant')
 
-    def visit_type(self, module: Module, node: ast.expr) -> type3types.Type3:
+    def visit_type(self, module: Module, node: ast.expr) -> Type3:
         if isinstance(node, ast.Constant):
             if node.value is None:
                 return prelude.none
@@ -669,7 +623,7 @@ class OurVisitor:
 
             return prelude.static_array(
                 self.visit_type(module, node.value),
-                type3types.IntType3(node.slice.value),
+                IntType3(node.slice.value),
             )
 
         if isinstance(node, ast.Tuple):

phasm/prelude/__init__.py

@@ -1,50 +1,129 @@
 """
 The prelude are all the builtin types, type classes and methods
 """
+from typing import Any, Callable
+from warnings import warn
 
-from ..type3.functions import TypeVariable
+from phasm.stdlib import types as stdtypes
-from ..type3.typeclasses import Type3Class, instance_type_class
+from phasm.wasmgenerator import Generator
+
+from ..type3.functions import (
+    Constraint_TypeClassInstanceExists,
+    TypeConstructorVariable,
+    TypeVariable,
+    TypeVariableApplication_Nullary,
+)
+from ..type3.routers import TypeClassArgsRouter, TypeVariableLookup
+from ..type3.typeclasses import Type3Class, Type3ClassMethod
 from ..type3.types import (
+    IntType3,
     Type3,
+    TypeApplication_Nullary,
+    TypeConstructor_Base,
     TypeConstructor_StaticArray,
     TypeConstructor_Struct,
     TypeConstructor_Tuple,
 )
 
-none = Type3('none', [])
+PRELUDE_TYPE_CLASS_INSTANCES_EXISTING: set[tuple[Type3Class, tuple[Type3 | TypeConstructor_Base[Any], ...]]] = set()
+
+PRELUDE_TYPE_CLASS_INSTANCE_METHODS: dict[Type3ClassMethod, TypeClassArgsRouter[Generator, None]] = {}
+
+class MissingImplementationException(Exception):
+    pass
+
+class MissingImplementationWarning(Warning):
+    pass
+
+def instance_type_class(
+        cls: Type3Class,
+        *typ: Type3 | TypeConstructor_Base[Any],
+        methods: dict[str, Callable[[Generator, TypeVariableLookup], None]] = {},
+        operators: dict[str, Callable[[Generator, TypeVariableLookup], None]] = {},
+) -> None:
+    global PRELUDE_TYPE_CLASS_INSTANCES_EXISTING
+    global PRELUDE_TYPE_CLASS_INSTANCE_METHODS
+
+    assert len(cls.args) == len(typ)
+
+    tv_map: dict[TypeVariable, Type3] = {}
+    tc_map: dict[TypeConstructorVariable, TypeConstructor_Base[Any]] = {}
+    for arg_tv, arg_tp in zip(cls.args, typ, strict=True):
+        if isinstance(arg_tv, TypeVariable):
+            assert isinstance(arg_tp, Type3)
+            tv_map[arg_tv] = arg_tp
+        elif isinstance(arg_tv, TypeConstructorVariable):
+            assert isinstance(arg_tp, TypeConstructor_Base)
+            tc_map[arg_tv] = arg_tp
+        else:
+            raise NotImplementedError(arg_tv, arg_tp)
+
+    # TODO: Check for required existing instantiations
+
+    PRELUDE_TYPE_CLASS_INSTANCES_EXISTING.add((cls, tuple(typ), ))
+
+    for method_name, method in cls.methods.items():
+        router = PRELUDE_TYPE_CLASS_INSTANCE_METHODS.get(method)
+        if router is None:
+            router = TypeClassArgsRouter[Generator, None](cls.args)
+            PRELUDE_TYPE_CLASS_INSTANCE_METHODS[method] = router
+
+        try:
+            generator = methods[method_name]
+        except KeyError:
+            warn(MissingImplementationWarning(str(method), cls.name + ' ' + ' '.join(x.name for x in typ)))
+            continue
+
+        router.add(tv_map, tc_map, generator)
+
+    for operator_name, operator in cls.operators.items():
+        router = PRELUDE_TYPE_CLASS_INSTANCE_METHODS.get(operator)
+        if router is None:
+            router = TypeClassArgsRouter[Generator, None](cls.args)
+            PRELUDE_TYPE_CLASS_INSTANCE_METHODS[operator] = router
+
+        try:
+            generator = operators[operator_name]
+        except KeyError:
+            warn(MissingImplementationWarning(str(operator), cls.name + ' ' + ' '.join(x.name for x in typ)))
+            continue
+
+        router.add(tv_map, tc_map, generator)
+
+none = Type3('none', TypeApplication_Nullary(None, None))
 """
 The none type, for when functions simply don't return anything. e.g., IO().
 """
 
-bool_ = Type3('bool', [])
+bool_ = Type3('bool', TypeApplication_Nullary(None, None))
 """
 The bool type, either True or False
 
 Suffixes with an underscores, as it's a Python builtin
 """
 
-u8 = Type3('u8', [])
+u8 = Type3('u8', TypeApplication_Nullary(None, None))
 """
 The unsigned 8-bit integer type.
 
 Operations on variables employ modular arithmetic, with modulus 2^8.
 """
 
-u32 = Type3('u32', [])
+u32 = Type3('u32', TypeApplication_Nullary(None, None))
 """
 The unsigned 32-bit integer type.
 
 Operations on variables employ modular arithmetic, with modulus 2^32.
 """
 
-u64 = Type3('u64', [])
+u64 = Type3('u64', TypeApplication_Nullary(None, None))
 """
 The unsigned 64-bit integer type.
 
 Operations on variables employ modular arithmetic, with modulus 2^64.
 """
 
-i8 = Type3('i8', [])
+i8 = Type3('i8', TypeApplication_Nullary(None, None))
 """
 The signed 8-bit integer type.
 
@@ -52,7 +131,7 @@ Operations on variables employ modular arithmetic, with modulus 2^8, but
 with the middel point being 0.
 """
 
-i32 = Type3('i32', [])
+i32 = Type3('i32', TypeApplication_Nullary(None, None))
 """
 The unsigned 32-bit integer type.
 
@@ -60,7 +139,7 @@ Operations on variables employ modular arithmetic, with modulus 2^32, but
 with the middel point being 0.
 """
 
-i64 = Type3('i64', [])
+i64 = Type3('i64', TypeApplication_Nullary(None, None))
 """
 The unsigned 64-bit integer type.
 
@@ -68,22 +147,25 @@ Operations on variables employ modular arithmetic, with modulus 2^64, but
 with the middel point being 0.
 """
 
-f32 = Type3('f32', [])
+f32 = Type3('f32', TypeApplication_Nullary(None, None))
 """
 A 32-bits IEEE 754 float, of 32 bits width.
 """
 
-f64 = Type3('f64', [])
+f64 = Type3('f64', TypeApplication_Nullary(None, None))
 """
 A 32-bits IEEE 754 float, of 64 bits width.
 """
 
-bytes_ = Type3('bytes', [])
+bytes_ = Type3('bytes', TypeApplication_Nullary(None, None))
 """
 This is a runtime-determined length piece of memory that can be indexed at runtime.
 """
 
-static_array = TypeConstructor_StaticArray('static_array', [], [])
+def sa_on_create(args: tuple[Type3, IntType3], typ: Type3) -> None:
+    instance_type_class(InternalPassAsPointer, typ)
+
+static_array = TypeConstructor_StaticArray('static_array', on_create=sa_on_create)
 """
 A type constructor.
 
@@ -93,7 +175,10 @@ It should be applied with one argument. It has a runtime-dynamic length
 of the same type repeated.
 """
 
-tuple_ = TypeConstructor_Tuple('tuple', [], [])
+def tp_on_create(args: tuple[Type3, ...], typ: Type3) -> None:
+    instance_type_class(InternalPassAsPointer, typ)
+
+tuple_ = TypeConstructor_Tuple('tuple', on_create=tp_on_create)
 """
 This is a fixed length piece of memory.
 
@@ -101,7 +186,10 @@ It should be applied with zero or more arguments. It has a compile time
 determined length, and each argument can be different.
 """
 
-struct = TypeConstructor_Struct('struct', [], [])
+def st_on_create(args: tuple[tuple[str, Type3], ...], typ: Type3) -> None:
+    instance_type_class(InternalPassAsPointer, typ)
+
+struct = TypeConstructor_Struct('struct', on_create=st_on_create)
 """
 This is like a tuple, but each argument is named, so that developers
 can get and set fields by name.
@@ -121,36 +209,61 @@ PRELUDE_TYPES: dict[str, Type3] = {
     'bytes': bytes_,
 }
 
-a = TypeVariable('a')
+a = TypeVariable('a', TypeVariableApplication_Nullary(None, None))
+b = TypeVariable('b', TypeVariableApplication_Nullary(None, None))
 
+t = TypeConstructorVariable('t')
 
-InternalPassAsPointer = Type3Class('InternalPassAsPointer', [a], methods={}, operators={})
+InternalPassAsPointer = Type3Class('InternalPassAsPointer', (a, ), methods={}, operators={})
 """
 Internal type class to keep track which types we pass arounds as a pointer.
 """
 
 instance_type_class(InternalPassAsPointer, bytes_)
-instance_type_class(InternalPassAsPointer, static_array)
+# instance_type_class(InternalPassAsPointer, static_array)
-instance_type_class(InternalPassAsPointer, tuple_)
+# instance_type_class(InternalPassAsPointer, tuple_)
-instance_type_class(InternalPassAsPointer, struct)
+# instance_type_class(InternalPassAsPointer, struct)
 
-Eq = Type3Class('Eq', [a], methods={}, operators={
+Eq = Type3Class('Eq', (a, ), methods={}, operators={
     '==': [a, a, bool_],
     '!=': [a, a, bool_],
     # FIXME: Do we want to expose 'eqz'? Or is that a compiler optimization?
 })
 
-instance_type_class(Eq, u8)
+instance_type_class(Eq, u8, operators={
-instance_type_class(Eq, u32)
+    '==': stdtypes.u8_eq_equals,
-instance_type_class(Eq, u64)
+    '!=': stdtypes.u8_eq_not_equals,
-instance_type_class(Eq, i8)
+})
-instance_type_class(Eq, i32)
+instance_type_class(Eq, u32, operators={
-instance_type_class(Eq, i64)
+    '==': stdtypes.u32_eq_equals,
-instance_type_class(Eq, f32)
+    '!=': stdtypes.u32_eq_not_equals,
-instance_type_class(Eq, f64)
+})
-instance_type_class(Eq, static_array)
+instance_type_class(Eq, u64, operators={
+    '==': stdtypes.u64_eq_equals,
+    '!=': stdtypes.u64_eq_not_equals,
+})
+instance_type_class(Eq, i8, operators={
+    '==': stdtypes.i8_eq_equals,
+    '!=': stdtypes.i8_eq_not_equals,
+})
+instance_type_class(Eq, i32, operators={
+    '==': stdtypes.i32_eq_equals,
+    '!=': stdtypes.i32_eq_not_equals,
+})
+instance_type_class(Eq, i64, operators={
+    '==': stdtypes.i64_eq_equals,
+    '!=': stdtypes.i64_eq_not_equals,
+})
+instance_type_class(Eq, f32, operators={
+    '==': stdtypes.f32_eq_equals,
+    '!=': stdtypes.f32_eq_not_equals,
+})
+instance_type_class(Eq, f64, operators={
+    '==': stdtypes.f64_eq_equals,
+    '!=': stdtypes.f64_eq_not_equals,
+})
 
-Ord = Type3Class('Ord', [a], methods={
+Ord = Type3Class('Ord', (a, ), methods={
     'min': [a, a, a],
     'max': [a, a, a],
 }, operators={
@@ -160,16 +273,80 @@ Ord = Type3Class('Ord', [a], methods={
     '>=': [a, a, bool_],
 }, inherited_classes=[Eq])
 
-instance_type_class(Ord, u8)
+instance_type_class(Ord, u8, methods={
-instance_type_class(Ord, u32)
+    'min': stdtypes.u8_ord_min,
-instance_type_class(Ord, u64)
+    'max': stdtypes.u8_ord_max,
-instance_type_class(Ord, i8)
+}, operators={
-instance_type_class(Ord, i32)
+    '<': stdtypes.u8_ord_less_than,
-instance_type_class(Ord, i64)
+    '<=': stdtypes.u8_ord_less_than_or_equal,
-instance_type_class(Ord, f32)
+    '>': stdtypes.u8_ord_greater_than,
-instance_type_class(Ord, f64)
+    '>=': stdtypes.u8_ord_greater_than_or_equal,
+})
+instance_type_class(Ord, u32, methods={
+    'min': stdtypes.u32_ord_min,
+    'max': stdtypes.u32_ord_max,
+}, operators={
+    '<': stdtypes.u32_ord_less_than,
+    '<=': stdtypes.u32_ord_less_than_or_equal,
+    '>': stdtypes.u32_ord_greater_than,
+    '>=': stdtypes.u32_ord_greater_than_or_equal,
+})
+instance_type_class(Ord, u64, methods={
+    'min': stdtypes.u64_ord_min,
+    'max': stdtypes.u64_ord_max,
+}, operators={
+    '<': stdtypes.u64_ord_less_than,
+    '<=': stdtypes.u64_ord_less_than_or_equal,
+    '>': stdtypes.u64_ord_greater_than,
+    '>=': stdtypes.u64_ord_greater_than_or_equal,
+})
+instance_type_class(Ord, i8, methods={
+    'min': stdtypes.i8_ord_min,
+    'max': stdtypes.i8_ord_max,
+}, operators={
+    '<': stdtypes.i8_ord_less_than,
+    '<=': stdtypes.i8_ord_less_than_or_equal,
+    '>': stdtypes.i8_ord_greater_than,
+    '>=': stdtypes.i8_ord_greater_than_or_equal,
+})
+instance_type_class(Ord, i32, methods={
+    'min': stdtypes.i32_ord_min,
+    'max': stdtypes.i32_ord_max,
+}, operators={
+    '<': stdtypes.i32_ord_less_than,
+    '<=': stdtypes.i32_ord_less_than_or_equal,
+    '>': stdtypes.i32_ord_greater_than,
+    '>=': stdtypes.i32_ord_greater_than_or_equal,
+})
+instance_type_class(Ord, i64, methods={
+    'min': stdtypes.i64_ord_min,
+    'max': stdtypes.i64_ord_max,
+}, operators={
+    '<': stdtypes.i64_ord_less_than,
+    '<=': stdtypes.i64_ord_less_than_or_equal,
+    '>': stdtypes.i64_ord_greater_than,
+    '>=': stdtypes.i64_ord_greater_than_or_equal,
+})
+instance_type_class(Ord, f32, methods={
+    'min': stdtypes.f32_ord_min,
+    'max': stdtypes.f32_ord_max,
+}, operators={
+    '<': stdtypes.f32_ord_less_than,
+    '<=': stdtypes.f32_ord_less_than_or_equal,
+    '>': stdtypes.f32_ord_greater_than,
+    '>=': stdtypes.f32_ord_greater_than_or_equal,
+})
+instance_type_class(Ord, f64, methods={
+    'min': stdtypes.f64_ord_min,
+    'max': stdtypes.f64_ord_max,
+}, operators={
+    '<': stdtypes.f64_ord_less_than,
+    '<=': stdtypes.f64_ord_less_than_or_equal,
+    '>': stdtypes.f64_ord_greater_than,
+    '>=': stdtypes.f64_ord_greater_than_or_equal,
+})
 
-Bits = Type3Class('Bits', [a], methods={
+Bits = Type3Class('Bits', (a, ), methods={
     'shl': [a, u32, a], # Logical shift left
     'shr': [a, u32, a], # Logical shift right
     'rotl': [a, u32, a], # Rotate bits left
@@ -181,11 +358,38 @@ Bits = Type3Class('Bits', [a], methods={
     '^': [a, a, a], # Bit-wise xor
 })
 
-instance_type_class(Bits, u8)
+instance_type_class(Bits, u8, methods={
-instance_type_class(Bits, u32)
+    'shl': stdtypes.u8_bits_logical_shift_left,
-instance_type_class(Bits, u64)
+    'shr': stdtypes.u8_bits_logical_shift_right,
+    'rotl': stdtypes.u8_bits_rotate_left,
+    'rotr': stdtypes.u8_bits_rotate_right,
+}, operators={
+    '&': stdtypes.u8_bits_bitwise_and,
+    '|': stdtypes.u8_bits_bitwise_or,
+    '^': stdtypes.u8_bits_bitwise_xor,
+})
+instance_type_class(Bits, u32, methods={
+    'shl': stdtypes.u32_bits_logical_shift_left,
+    'shr': stdtypes.u32_bits_logical_shift_right,
+    'rotl': stdtypes.u32_bits_rotate_left,
+    'rotr': stdtypes.u32_bits_rotate_right,
+}, operators={
+    '&': stdtypes.u32_bits_bitwise_and,
+    '|': stdtypes.u32_bits_bitwise_or,
+    '^': stdtypes.u32_bits_bitwise_xor,
+})
+instance_type_class(Bits, u64, methods={
+    'shl': stdtypes.u64_bits_logical_shift_left,
+    'shr': stdtypes.u64_bits_logical_shift_right,
+    'rotl': stdtypes.u64_bits_rotate_left,
+    'rotr': stdtypes.u64_bits_rotate_right,
+}, operators={
+    '&': stdtypes.u64_bits_bitwise_and,
+    '|': stdtypes.u64_bits_bitwise_or,
+    '^': stdtypes.u64_bits_bitwise_xor,
+})
 
-NatNum = Type3Class('NatNum', [a], methods={}, operators={
+NatNum = Type3Class('NatNum', (a, ), methods={}, operators={
     '+': [a, a, a],
     '-': [a, a, a],
     '*': [a, a, a],
@@ -193,35 +397,95 @@ NatNum = Type3Class('NatNum', [a], methods={}, operators={
     '>>': [a, u32, a], # Arithmic shift right
 })
 
-instance_type_class(NatNum, u32)
+instance_type_class(NatNum, u32, operators={
-instance_type_class(NatNum, u64)
+    '+': stdtypes.u32_natnum_add,
-instance_type_class(NatNum, i32)
+    '-': stdtypes.u32_natnum_sub,
-instance_type_class(NatNum, i64)
+    '*': stdtypes.u32_natnum_mul,
-instance_type_class(NatNum, f32)
+    '<<': stdtypes.u32_natnum_arithmic_shift_left,
-instance_type_class(NatNum, f64)
+    '>>': stdtypes.u32_natnum_arithmic_shift_right,
+})
+instance_type_class(NatNum, u64, operators={
+    '+': stdtypes.u64_natnum_add,
+    '-': stdtypes.u64_natnum_sub,
+    '*': stdtypes.u64_natnum_mul,
+    '<<': stdtypes.u64_natnum_arithmic_shift_left,
+    '>>': stdtypes.u64_natnum_arithmic_shift_right,
+})
+instance_type_class(NatNum, i32, operators={
+    '+': stdtypes.i32_natnum_add,
+    '-': stdtypes.i32_natnum_sub,
+    '*': stdtypes.i32_natnum_mul,
+    '<<': stdtypes.i32_natnum_arithmic_shift_left,
+    '>>': stdtypes.i32_natnum_arithmic_shift_right,
+})
+instance_type_class(NatNum, i64, operators={
+    '+': stdtypes.i64_natnum_add,
+    '-': stdtypes.i64_natnum_sub,
+    '*': stdtypes.i64_natnum_mul,
+    '<<': stdtypes.i64_natnum_arithmic_shift_left,
+    '>>': stdtypes.i64_natnum_arithmic_shift_right,
+})
+instance_type_class(NatNum, f32, operators={
+    '+': stdtypes.f32_natnum_add,
+    '-': stdtypes.f32_natnum_sub,
+    '*': stdtypes.f32_natnum_mul,
+    '<<': stdtypes.f32_natnum_arithmic_shift_left,
+    '>>': stdtypes.f32_natnum_arithmic_shift_right,
+})
+instance_type_class(NatNum, f64, operators={
+    '+': stdtypes.f64_natnum_add,
+    '-': stdtypes.f64_natnum_sub,
+    '*': stdtypes.f64_natnum_mul,
+    '<<': stdtypes.f64_natnum_arithmic_shift_left,
+    '>>': stdtypes.f64_natnum_arithmic_shift_right,
+})
 
-IntNum = Type3Class('IntNum', [a], methods={
+IntNum = Type3Class('IntNum', (a, ), methods={
     'abs': [a, a],
     'neg': [a, a],
 }, operators={}, inherited_classes=[NatNum])
 
-instance_type_class(IntNum, i32)
+instance_type_class(IntNum, i32, methods={
-instance_type_class(IntNum, i64)
+    'abs': stdtypes.i32_intnum_abs,
-instance_type_class(IntNum, f32)
+    'neg': stdtypes.i32_intnum_neg,
-instance_type_class(IntNum, f64)
+})
+instance_type_class(IntNum, i64, methods={
+    'abs': stdtypes.i64_intnum_abs,
+    'neg': stdtypes.i64_intnum_neg,
+})
+instance_type_class(IntNum, f32, methods={
+    'abs': stdtypes.f32_intnum_abs,
+    'neg': stdtypes.f32_intnum_neg,
+})
+instance_type_class(IntNum, f64, methods={
+    'abs': stdtypes.f64_intnum_abs,
+    'neg': stdtypes.f64_intnum_neg,
+})
 
-Integral = Type3Class('Eq', [a], methods={
+Integral = Type3Class('Eq', (a, ), methods={
 }, operators={
     '//': [a, a, a],
     '%': [a, a, a],
 }, inherited_classes=[NatNum])
 
-instance_type_class(Integral, u32)
+instance_type_class(Integral, u32, operators={
-instance_type_class(Integral, u64)
+    '//': stdtypes.u32_integral_div,
-instance_type_class(Integral, i32)
+    '%': stdtypes.u32_integral_rem,
-instance_type_class(Integral, i64)
+})
+instance_type_class(Integral, u64, operators={
+    '//': stdtypes.u64_integral_div,
+    '%': stdtypes.u64_integral_rem,
+})
+instance_type_class(Integral, i32, operators={
+    '//': stdtypes.i32_integral_div,
+    '%': stdtypes.i32_integral_rem,
+})
+instance_type_class(Integral, i64, operators={
+    '//': stdtypes.i64_integral_div,
+    '%': stdtypes.i64_integral_rem,
+})
 
-Fractional = Type3Class('Fractional', [a], methods={
+Fractional = Type3Class('Fractional', (a, ), methods={
     'ceil': [a, a],
     'floor': [a, a],
     'trunc': [a, a],
@@ -230,23 +494,94 @@ Fractional = Type3Class('Fractional', [a], methods={
     '/': [a, a, a],
 }, inherited_classes=[NatNum])
 
-instance_type_class(Fractional, f32)
+instance_type_class(Fractional, f32, methods={
-instance_type_class(Fractional, f64)
+    'ceil': stdtypes.f32_fractional_ceil,
+    'floor': stdtypes.f32_fractional_floor,
+    'trunc': stdtypes.f32_fractional_trunc,
+    'nearest': stdtypes.f32_fractional_nearest,
+}, operators={
+    '/': stdtypes.f32_fractional_div,
+})
+instance_type_class(Fractional, f64, methods={
+    'ceil': stdtypes.f64_fractional_ceil,
+    'floor': stdtypes.f64_fractional_floor,
+    'trunc': stdtypes.f64_fractional_trunc,
+    'nearest': stdtypes.f64_fractional_nearest,
+}, operators={
+    '/': stdtypes.f64_fractional_div,
+})
 
-Floating = Type3Class('Floating', [a], methods={
+Floating = Type3Class('Floating', (a, ), methods={
     'sqrt': [a, a],
 }, operators={}, inherited_classes=[Fractional])
 
 # FIXME: Do we want to expose copysign?
 
-instance_type_class(Floating, f32)
+instance_type_class(Floating, f32, methods={
-instance_type_class(Floating, f64)
+    'sqrt': stdtypes.f32_floating_sqrt,
+})
+instance_type_class(Floating, f64, methods={
+    'sqrt': stdtypes.f64_floating_sqrt,
+})
 
-Sized_ = Type3Class('Sized', [a], methods={
+Sized_ = Type3Class('Sized', (a, ), methods={
     'len': [a, u32],
 }, operators={})  # FIXME: Once we get type class families, add [] here
 
-instance_type_class(Sized_, bytes_)
+instance_type_class(Sized_, bytes_, methods={
+    'len': stdtypes.bytes_sized_len,
+})
+
+Extendable = Type3Class('Extendable', (a, b, ), methods={
+    'extend': [a, b],
+    'wrap': [b, a],
+}, operators={})
+
+instance_type_class(Extendable, u8, u32, methods={
+    'extend': stdtypes.u8_u32_extend,
+    'wrap': stdtypes.u8_u32_wrap,
+})
+instance_type_class(Extendable, u8, u64, methods={
+    'extend': stdtypes.u8_u64_extend,
+    'wrap': stdtypes.u8_u64_wrap,
+})
+instance_type_class(Extendable, u32, u64, methods={
+    'extend': stdtypes.u32_u64_extend,
+    'wrap': stdtypes.u32_u64_wrap,
+})
+instance_type_class(Extendable, i8, i32, methods={
+    'extend': stdtypes.i8_i32_extend,
+    'wrap': stdtypes.i8_i32_wrap,
+})
+instance_type_class(Extendable, i8, i64, methods={
+    'extend': stdtypes.i8_i64_extend,
+    'wrap': stdtypes.i8_i64_wrap,
+})
+instance_type_class(Extendable, i32, i64, methods={
+    'extend': stdtypes.i32_i64_extend,
+    'wrap': stdtypes.i32_i64_wrap,
+})
+
+Promotable = Type3Class('Promotable', (a, b, ), methods={
+    'promote': [a, b],
+    'demote': [b, a],
+}, operators={})
+
+instance_type_class(Promotable, f32, f64, methods={
+    'promote': stdtypes.f32_f64_promote,
+    'demote': stdtypes.f32_f64_demote,
+})
+
+Foldable = Type3Class('Foldable', (t, ), methods={
+    'sum': [t(a), a],
+    'foldl': [[a, b, b], b, t(a), b],
+}, operators={}, additional_context={
+    'sum': [Constraint_TypeClassInstanceExists(NatNum, (a, ))],
+})
+
+instance_type_class(Foldable, static_array, methods={
+    'sum': stdtypes.static_array_sum,
+})
 
 PRELUDE_TYPE_CLASSES = {
     'Eq': Eq,
@@ -257,6 +592,8 @@ PRELUDE_TYPE_CLASSES = {
     'Integral': Integral,
     'Fractional': Fractional,
     'Floating': Floating,
+    'Extendable': Extendable,
+    'Promotable': Promotable,
 }
 
 PRELUDE_OPERATORS = {
@@ -279,4 +616,7 @@ PRELUDE_METHODS = {
     **IntNum.methods,
     **NatNum.methods,
     **Sized_.methods,
+    **Extendable.methods,
+    **Promotable.methods,
+    **Foldable.methods,
 }

phasm/runtime.py

@@ -1,8 +1,40 @@
 from . import prelude
-from .type3 import types as type3types
+from .type3.routers import NoRouteForTypeException, TypeApplicationRouter
+from .type3.types import IntType3, Type3
 
 
-def calculate_alloc_size(typ: type3types.Type3, is_member: bool = False) -> int:
+def calculate_alloc_size_static_array(is_member: bool, args: tuple[Type3, IntType3]) -> int:
+    if is_member:
+        return 4
+
+    sa_type, sa_len = args
+
+    return sa_len.value * calculate_alloc_size(sa_type, is_member=True)
+
+def calculate_alloc_size_tuple(is_member: bool, args: tuple[Type3, ...]) -> int:
+    if is_member:
+        return 4
+
+    return sum(
+        calculate_alloc_size(x, is_member=True)
+        for x in args
+    )
+
+def calculate_alloc_size_struct(is_member: bool, args: tuple[tuple[str, Type3], ...]) -> int:
+    if is_member:
+        return 4
+
+    return sum(
+        calculate_alloc_size(x, is_member=True)
+        for _, x in args
+    )
+
+ALLOC_SIZE_ROUTER = TypeApplicationRouter[bool, int]()
+ALLOC_SIZE_ROUTER.add(prelude.static_array, calculate_alloc_size_static_array)
+ALLOC_SIZE_ROUTER.add(prelude.struct, calculate_alloc_size_struct)
+ALLOC_SIZE_ROUTER.add(prelude.tuple_, calculate_alloc_size_tuple)
+
+def calculate_alloc_size(typ: Type3, is_member: bool = False) -> int:
     if typ in (prelude.u8, prelude.i8, ):
         return 4 # FIXME: We allocate 4 bytes for every u8 since you load them into an i32
 
@@ -12,51 +44,20 @@ def calculate_alloc_size(typ: type3types.Type3, is_member: bool = False) -> int:
     if typ in (prelude.u64, prelude.i64, prelude.f64, ):
         return 8
 
-    if typ == prelude.bytes_:
+    try:
+        return ALLOC_SIZE_ROUTER(is_member, typ)
+    except NoRouteForTypeException:
         if is_member:
+            # By default, 'boxed' or 'constructed' types are
+            # stored as pointers when a member of a struct or tuple
             return 4
 
-        raise NotImplementedError # When does this happen?
+        raise NotImplementedError(typ)
 
-    st_args = prelude.struct.did_construct(typ)
+def calculate_member_offset(st_name: str, st_args: tuple[tuple[str, Type3], ...], needle: str) -> int:
-    if st_args is not None:
-        if is_member:
-            # Structs referred to by other structs or tuples are pointers
-            return 4
-
-        return sum(
-            calculate_alloc_size(x, is_member=True)
-            for x in st_args.values()
-        )
-
-    sa_args = prelude.static_array.did_construct(typ)
-    if sa_args is not None:
-            if is_member:
-                # tuples referred to by other structs or tuples are pointers
-                return 4
-
-            sa_type, sa_len = sa_args
-
-            return sa_len.value * calculate_alloc_size(sa_type, is_member=True)
-
-    tp_args = prelude.tuple_.did_construct(typ)
-    if tp_args is not None:
-            if is_member:
-                # tuples referred to by other structs or tuples are pointers
-                return 4
-
-            size = 0
-            for arg in tp_args:
-                size += calculate_alloc_size(arg, is_member=True)
-
-            return size
-
-    raise NotImplementedError(calculate_alloc_size, typ)
-
-def calculate_member_offset(st_name: str, st_args: dict[str, type3types.Type3], needle: str) -> int:
     result = 0
 
-    for memnam, memtyp in st_args.items():
+    for memnam, memtyp in st_args:
         if needle == memnam:
             return result
 

phasm/stdlib/types.py

@@ -2,6 +2,8 @@
 stdlib: Standard types that are not wasm primitives
 """
 from phasm.stdlib import alloc
+from phasm.type3.routers import TypeVariableLookup
+from phasm.type3.types import IntType3, Type3
 from phasm.wasmgenerator import Generator, func_wrapper
 from phasm.wasmgenerator import VarType_i32 as i32
 from phasm.wasmgenerator import VarType_i64 as i64
@@ -39,8 +41,7 @@ def __subscript_bytes__(g: Generator, adr: i32, ofs: i32) -> i32:
     Returns an index from a bytes value
 
     If ofs is more than the length of the bytes, this
-    function returns 0, following the 'no undefined behaviour'
+    function stop as unreachable.
-    philosophy.
 
     adr   i32    The pointer for the allocated bytes
     ofs   i32    The offset within the allocated bytes
@@ -388,444 +389,579 @@ def __u8_rotr__(g: Generator, x: i32, r: i32) -> i32:
 ## ###
 ## class Eq
 
-def u8_eq_equals(g: Generator) -> None:
+def u8_eq_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.eq()
 
-def u32_eq_equals(g: Generator) -> None:
+def u32_eq_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.eq()
 
-def u64_eq_equals(g: Generator) -> None:
+def u64_eq_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.eq()
 
-def i8_eq_equals(g: Generator) -> None:
+def i8_eq_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.eq()
 
-def i32_eq_equals(g: Generator) -> None:
+def i32_eq_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.eq()
 
-def i64_eq_equals(g: Generator) -> None:
+def i64_eq_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.eq()
 
-def f32_eq_equals(g: Generator) -> None:
+def f32_eq_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.eq()
 
-def f64_eq_equals(g: Generator) -> None:
+def f64_eq_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.eq()
 
-def u8_eq_not_equals(g: Generator) -> None:
+def u8_eq_not_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.ne()
 
-def u32_eq_not_equals(g: Generator) -> None:
+def u32_eq_not_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.ne()
 
-def u64_eq_not_equals(g: Generator) -> None:
+def u64_eq_not_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.ne()
 
-def i8_eq_not_equals(g: Generator) -> None:
+def i8_eq_not_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.ne()
 
-def i32_eq_not_equals(g: Generator) -> None:
+def i32_eq_not_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.ne()
 
-def i64_eq_not_equals(g: Generator) -> None:
+def i64_eq_not_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.ne()
 
-def f32_eq_not_equals(g: Generator) -> None:
+def f32_eq_not_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.ne()
 
-def f64_eq_not_equals(g: Generator) -> None:
+def f64_eq_not_equals(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.ne()
 
 ## ###
 ## class Ord
 
-def u8_ord_min(g: Generator) -> None:
+def u8_ord_min(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u32_ord_min__')
 
-def u32_ord_min(g: Generator) -> None:
+def u32_ord_min(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u32_ord_min__')
 
-def u64_ord_min(g: Generator) -> None:
+def u64_ord_min(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u64_ord_min__')
 
-def i8_ord_min(g: Generator) -> None:
+def i8_ord_min(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__i32_ord_min__')
 
-def i32_ord_min(g: Generator) -> None:
+def i32_ord_min(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__i32_ord_min__')
 
-def i64_ord_min(g: Generator) -> None:
+def i64_ord_min(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__i64_ord_min__')
 
-def f32_ord_min(g: Generator) -> None:
+def f32_ord_min(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.min()
 
-def f64_ord_min(g: Generator) -> None:
+def f64_ord_min(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.min()
 
-def u8_ord_max(g: Generator) -> None:
+def u8_ord_max(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u32_ord_max__')
 
-def u32_ord_max(g: Generator) -> None:
+def u32_ord_max(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u32_ord_max__')
 
-def u64_ord_max(g: Generator) -> None:
+def u64_ord_max(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u64_ord_max__')
 
-def i8_ord_max(g: Generator) -> None:
+def i8_ord_max(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__i32_ord_max__')
 
-def i32_ord_max(g: Generator) -> None:
+def i32_ord_max(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__i32_ord_max__')
 
-def i64_ord_max(g: Generator) -> None:
+def i64_ord_max(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__i64_ord_max__')
 
-def f32_ord_max(g: Generator) -> None:
+def f32_ord_max(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.max()
 
-def f64_ord_max(g: Generator) -> None:
+def f64_ord_max(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.max()
 
 
-def u8_ord_less_than(g: Generator) -> None:
+def u8_ord_less_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.lt_u()
 
-def u32_ord_less_than(g: Generator) -> None:
+def u32_ord_less_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.lt_u()
 
-def u64_ord_less_than(g: Generator) -> None:
+def u64_ord_less_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.lt_u()
 
-def i8_ord_less_than(g: Generator) -> None:
+def i8_ord_less_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.lt_s()
 
-def i32_ord_less_than(g: Generator) -> None:
+def i32_ord_less_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.lt_s()
 
-def i64_ord_less_than(g: Generator) -> None:
+def i64_ord_less_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.lt_s()
 
-def f32_ord_less_than(g: Generator) -> None:
+def f32_ord_less_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.lt()
 
-def f64_ord_less_than(g: Generator) -> None:
+def f64_ord_less_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.lt()
 
-def u8_ord_less_than_or_equal(g: Generator) -> None:
+def u8_ord_less_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.le_u()
 
-def u32_ord_less_than_or_equal(g: Generator) -> None:
+def u32_ord_less_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.le_u()
 
-def u64_ord_less_than_or_equal(g: Generator) -> None:
+def u64_ord_less_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.le_u()
 
-def i8_ord_less_than_or_equal(g: Generator) -> None:
+def i8_ord_less_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.le_s()
 
-def i32_ord_less_than_or_equal(g: Generator) -> None:
+def i32_ord_less_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.le_s()
 
-def i64_ord_less_than_or_equal(g: Generator) -> None:
+def i64_ord_less_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.le_s()
 
-def f32_ord_less_than_or_equal(g: Generator) -> None:
+def f32_ord_less_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.le()
 
-def f64_ord_less_than_or_equal(g: Generator) -> None:
+def f64_ord_less_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.le()
 
-def u8_ord_greater_than(g: Generator) -> None:
+def u8_ord_greater_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.gt_u()
 
-def u32_ord_greater_than(g: Generator) -> None:
+def u32_ord_greater_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.gt_u()
 
-def u64_ord_greater_than(g: Generator) -> None:
+def u64_ord_greater_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.gt_u()
 
-def i8_ord_greater_than(g: Generator) -> None:
+def i8_ord_greater_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.gt_s()
 
-def i32_ord_greater_than(g: Generator) -> None:
+def i32_ord_greater_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.gt_s()
 
-def i64_ord_greater_than(g: Generator) -> None:
+def i64_ord_greater_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.gt_s()
 
-def f32_ord_greater_than(g: Generator) -> None:
+def f32_ord_greater_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.gt()
 
-def f64_ord_greater_than(g: Generator) -> None:
+def f64_ord_greater_than(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.gt()
 
-def u8_ord_greater_than_or_equal(g: Generator) -> None:
+def u8_ord_greater_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.ge_u()
 
-def u32_ord_greater_than_or_equal(g: Generator) -> None:
+def u32_ord_greater_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.ge_u()
 
-def u64_ord_greater_than_or_equal(g: Generator) -> None:
+def u64_ord_greater_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.ge_u()
 
-def i8_ord_greater_than_or_equal(g: Generator) -> None:
+def i8_ord_greater_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.ge_s()
 
-def i32_ord_greater_than_or_equal(g: Generator) -> None:
+def i32_ord_greater_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.ge_s()
 
-def i64_ord_greater_than_or_equal(g: Generator) -> None:
+def i64_ord_greater_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.ge_s()
 
-def f32_ord_greater_than_or_equal(g: Generator) -> None:
+def f32_ord_greater_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.ge()
 
-def f64_ord_greater_than_or_equal(g: Generator) -> None:
+def f64_ord_greater_than_or_equal(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.ge()
 
 ## ###
 ## class Bits
 
-def u8_bits_logical_shift_left(g: Generator) -> None:
+def u8_bits_logical_shift_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.shl()
     g.i32.const(255)
     g.i32.and_()
 
-def u32_bits_logical_shift_left(g: Generator) -> None:
+def u32_bits_logical_shift_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.shl()
 
-def u64_bits_logical_shift_left(g: Generator) -> None:
+def u64_bits_logical_shift_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.extend_i32_u()
     g.i64.shl()
 
-def u8_bits_logical_shift_right(g: Generator) -> None:
+def u8_bits_logical_shift_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.shr_u()
 
-def u32_bits_logical_shift_right(g: Generator) -> None:
+def u32_bits_logical_shift_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.shr_u()
 
-def u64_bits_logical_shift_right(g: Generator) -> None:
+def u64_bits_logical_shift_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.extend_i32_u()
     g.i64.shr_u()
 
-def u8_bits_rotate_left(g: Generator) -> None:
+def u8_bits_rotate_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u8_rotl__')
 
-def u32_bits_rotate_left(g: Generator) -> None:
+def u32_bits_rotate_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.rotl()
 
-def u64_bits_rotate_left(g: Generator) -> None:
+def u64_bits_rotate_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.extend_i32_u()
     g.i64.rotl()
 
-def u8_bits_rotate_right(g: Generator) -> None:
+def u8_bits_rotate_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u8_rotr__')
 
-def u32_bits_rotate_right(g: Generator) -> None:
+def u32_bits_rotate_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.rotr()
 
-def u64_bits_rotate_right(g: Generator) -> None:
+def u64_bits_rotate_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.extend_i32_u()
     g.i64.rotr()
 
-def u8_bits_bitwise_and(g: Generator) -> None:
+def u8_bits_bitwise_and(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.and_()
 
-def u32_bits_bitwise_and(g: Generator) -> None:
+def u32_bits_bitwise_and(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.and_()
 
-def u64_bits_bitwise_and(g: Generator) -> None:
+def u64_bits_bitwise_and(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.and_()
 
-def u8_bits_bitwise_or(g: Generator) -> None:
+def u8_bits_bitwise_or(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.or_()
 
-def u32_bits_bitwise_or(g: Generator) -> None:
+def u32_bits_bitwise_or(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.or_()
 
-def u64_bits_bitwise_or(g: Generator) -> None:
+def u64_bits_bitwise_or(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.or_()
 
-def u8_bits_bitwise_xor(g: Generator) -> None:
+def u8_bits_bitwise_xor(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.xor()
 
-def u32_bits_bitwise_xor(g: Generator) -> None:
+def u32_bits_bitwise_xor(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.xor()
 
-def u64_bits_bitwise_xor(g: Generator) -> None:
+def u64_bits_bitwise_xor(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.xor()
 
 ## ###
 ## class Fractional
 
-def f32_fractional_ceil(g: Generator) -> None:
+def f32_fractional_ceil(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.ceil()
 
-def f64_fractional_ceil(g: Generator) -> None:
+def f64_fractional_ceil(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.ceil()
 
-def f32_fractional_floor(g: Generator) -> None:
+def f32_fractional_floor(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.floor()
 
-def f64_fractional_floor(g: Generator) -> None:
+def f64_fractional_floor(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.floor()
 
-def f32_fractional_trunc(g: Generator) -> None:
+def f32_fractional_trunc(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.trunc()
 
-def f64_fractional_trunc(g: Generator) -> None:
+def f64_fractional_trunc(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.trunc()
 
-def f32_fractional_nearest(g: Generator) -> None:
+def f32_fractional_nearest(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.nearest()
 
-def f64_fractional_nearest(g: Generator) -> None:
+def f64_fractional_nearest(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.nearest()
 
-def f32_fractional_div(g: Generator) -> None:
+def f32_fractional_div(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.div()
 
-def f64_fractional_div(g: Generator) -> None:
+def f64_fractional_div(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.div()
 
 ## ###
 ## class Floating
 
-def f32_floating_sqrt(g: Generator) -> None:
+def f32_floating_sqrt(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('f32.sqrt')
 
-def f64_floating_sqrt(g: Generator) -> None:
+def f64_floating_sqrt(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('f64.sqrt')
 
 ## ###
 ## class Integral
 
-def u32_integral_div(g: Generator) -> None:
+def u32_integral_div(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.div_u')
 
-def u64_integral_div(g: Generator) -> None:
+def u64_integral_div(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.div_u')
 
-def i32_integral_div(g: Generator) -> None:
+def i32_integral_div(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.div_s')
 
-def i64_integral_div(g: Generator) -> None:
+def i64_integral_div(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.div_s')
 
-def u32_integral_rem(g: Generator) -> None:
+def u32_integral_rem(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.rem_u')
 
-def u64_integral_rem(g: Generator) -> None:
+def u64_integral_rem(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.rem_u')
 
-def i32_integral_rem(g: Generator) -> None:
+def i32_integral_rem(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.rem_s')
 
-def i64_integral_rem(g: Generator) -> None:
+def i64_integral_rem(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.rem_s')
 
 ## ###
 ## class NatNum
 
-def u32_natnum_add(g: Generator) -> None:
+def u32_natnum_add(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.add')
 
-def u64_natnum_add(g: Generator) -> None:
+def u64_natnum_add(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.add')
 
-def i32_natnum_add(g: Generator) -> None:
+def i32_natnum_add(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.add')
 
-def i64_natnum_add(g: Generator) -> None:
+def i64_natnum_add(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.add')
 
-def f32_natnum_add(g: Generator) -> None:
+def f32_natnum_add(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('f32.add')
 
-def f64_natnum_add(g: Generator) -> None:
+def f64_natnum_add(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('f64.add')
 
-def u32_natnum_sub(g: Generator) -> None:
+def u32_natnum_sub(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.sub')
 
-def u64_natnum_sub(g: Generator) -> None:
+def u64_natnum_sub(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.sub')
 
-def i32_natnum_sub(g: Generator) -> None:
+def i32_natnum_sub(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.sub')
 
-def i64_natnum_sub(g: Generator) -> None:
+def i64_natnum_sub(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.sub')
 
-def f32_natnum_sub(g: Generator) -> None:
+def f32_natnum_sub(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('f32.sub')
 
-def f64_natnum_sub(g: Generator) -> None:
+def f64_natnum_sub(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('f64.sub')
 
-def u32_natnum_mul(g: Generator) -> None:
+def u32_natnum_mul(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.mul')
 
-def u64_natnum_mul(g: Generator) -> None:
+def u64_natnum_mul(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.mul')
 
-def i32_natnum_mul(g: Generator) -> None:
+def i32_natnum_mul(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i32.mul')
 
-def i64_natnum_mul(g: Generator) -> None:
+def i64_natnum_mul(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('i64.mul')
 
-def f32_natnum_mul(g: Generator) -> None:
+def f32_natnum_mul(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('f32.mul')
 
-def f64_natnum_mul(g: Generator) -> None:
+def f64_natnum_mul(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('f64.mul')
 
-def u32_natnum_arithmic_shift_left(g: Generator) -> None:
+def u32_natnum_arithmic_shift_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.shl()
 
-def u64_natnum_arithmic_shift_left(g: Generator) -> None:
+def u64_natnum_arithmic_shift_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.extend_i32_u()
     g.i64.shl()
 
-def i32_natnum_arithmic_shift_left(g: Generator) -> None:
+def i32_natnum_arithmic_shift_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.shl()
 
-def i64_natnum_arithmic_shift_left(g: Generator) -> None:
+def i64_natnum_arithmic_shift_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.extend_i32_u()
     g.i64.shl()
 
-def f32_natnum_arithmic_shift_left(g: Generator) -> None:
+def f32_natnum_arithmic_shift_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u32_pow2__')
     g.f32.convert_i32_u()
     g.f32.mul()
 
-def f64_natnum_arithmic_shift_left(g: Generator) -> None:
+def f64_natnum_arithmic_shift_left(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u32_pow2__')
     g.f64.convert_i32_u()
     g.f64.mul()
 
-def u32_natnum_arithmic_shift_right(g: Generator) -> None:
+def u32_natnum_arithmic_shift_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.shr_u()
 
-def u64_natnum_arithmic_shift_right(g: Generator) -> None:
+def u64_natnum_arithmic_shift_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.extend_i32_u()
     g.i64.shr_u()
 
-def i32_natnum_arithmic_shift_right(g: Generator) -> None:
+def i32_natnum_arithmic_shift_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.shr_s()
 
-def i64_natnum_arithmic_shift_right(g: Generator) -> None:
+def i64_natnum_arithmic_shift_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.extend_i32_u()
     g.i64.shr_s()
 
-def f32_natnum_arithmic_shift_right(g: Generator) -> None:
+def f32_natnum_arithmic_shift_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u32_pow2__')
     g.f32.convert_i32_u()
     g.f32.div()
 
-def f64_natnum_arithmic_shift_right(g: Generator) -> None:
+def f64_natnum_arithmic_shift_right(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__u32_pow2__')
     g.f64.convert_i32_u()
     g.f64.div()
@@ -833,35 +969,219 @@ def f64_natnum_arithmic_shift_right(g: Generator) -> None:
 ## ###
 ## class IntNum
 
-def i32_intnum_abs(g: Generator) -> None:
+def i32_intnum_abs(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__i32_intnum_abs__')
 
-def i64_intnum_abs(g: Generator) -> None:
+def i64_intnum_abs(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.add_statement('call $stdlib.types.__i64_intnum_abs__')
 
-def f32_intnum_abs(g: Generator) -> None:
+def f32_intnum_abs(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.abs()
 
-def f64_intnum_abs(g: Generator) -> None:
+def f64_intnum_abs(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.abs()
 
-def i32_intnum_neg(g: Generator) -> None:
+def i32_intnum_neg(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i32.const(-1)
     g.i32.mul()
 
-def i64_intnum_neg(g: Generator) -> None:
+def i64_intnum_neg(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.i64.const(-1)
     g.i64.mul()
 
-def f32_intnum_neg(g: Generator) -> None:
+def f32_intnum_neg(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f32.neg()
 
-def f64_intnum_neg(g: Generator) -> None:
+def f64_intnum_neg(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     g.f64.neg()
 
 ## ###
 ## Class Sized
 
-def bytes_sized_len(g: Generator) -> None:
+def bytes_sized_len(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
     # The length is stored in the first 4 bytes
     g.i32.load()
+
+## ###
+## Extendable
+
+def u8_u32_extend(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    # No-op
+    # u8 is already stored as u32
+    pass
+
+def u8_u64_extend(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i64.extend_i32_u()
+
+def u32_u64_extend(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i64.extend_i32_u()
+
+def i8_i32_extend(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    # No-op
+    # i8 is already stored as i32
+    pass
+
+def i8_i64_extend(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i64.extend_i32_s()
+
+def i32_i64_extend(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i64.extend_i32_s()
+
+def u8_u32_wrap(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i32.const(0xFF)
+    g.i32.and_()
+
+def u8_u64_wrap(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i32.wrap_i64()
+    g.i32.const(0xFF)
+    g.i32.and_()
+
+def u32_u64_wrap(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i32.wrap_i64()
+
+def i8_i32_wrap(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i32.const(0xFF)
+    g.i32.and_()
+
+def i8_i64_wrap(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i32.wrap_i64()
+
+def i32_i64_wrap(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.i32.wrap_i64()
+
+## ###
+## Promotable
+
+def f32_f64_promote(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.f64.promote_f32()
+
+def f32_f64_demote(g: Generator, tv_map: TypeVariableLookup) -> None:
+    del tv_map
+    g.f32.demote_f64()
+
+def static_array_sum(g: Generator, tv_map: TypeVariableLookup) -> None:
+    assert len(tv_map) == 1
+    sa_type, sa_len = next(iter(tv_map.values()))
+    assert isinstance(sa_type, Type3)
+    assert isinstance(sa_len, IntType3)
+
+    if sa_len.value < 1:
+        raise NotImplementedError('Default value in case sum is empty')
+
+    # FIXME: We should probably use LOAD_STORE_TYPE_MAP for this?
+    mtyp_map = {
+        'u32': 'i32',
+        'u64': 'i64',
+        'i32': 'i32',
+        'i64': 'i64',
+        'f32': 'f32',
+        'f64': 'f64',
+    }
+
+    # FIXME: We should probably use calc_alloc_size for this?
+    type_var_size_map = {
+        'u32': 4,
+        'u64': 8,
+        'i32': 4,
+        'i64': 8,
+        'f32': 4,
+        'f64': 8,
+    }
+
+    type_var_add_generator = {
+        'u32': u32_natnum_add,
+        'u64': u64_natnum_add,
+        'i32': i32_natnum_add,
+        'i64': i64_natnum_add,
+        'f32': f32_natnum_add,
+        'f64': f64_natnum_add,
+    }
+
+    # By default, constructed types are passed as pointers
+    # FIXME: We don't know what add function to call
+    sa_type_mtyp = mtyp_map.get(sa_type.name, 'i32')
+    sa_type_alloc_size = type_var_size_map.get(sa_type.name, 4)
+    sa_type_add_gen = type_var_add_generator[sa_type.name]
+
+    # Definitions
+    sum_adr = g.temp_var(i32('sum_adr'))
+    sum_stop = g.temp_var(i32('sum_stop'))
+
+    # Stack before: [adr]
+    # Stack after:  [sum]
+
+    # adr = {address of what's currently on stack}
+    # Stack: [adr] -> []
+    g.nop(comment=f'Start sum for {sa_type.name}[{sa_len.value}]')
+    g.local.set(sum_adr)
+
+    # stop = adr + ar_len * sa_type_alloc_size
+    # Stack: []
+    g.nop(comment='Calculate address at which to stop looping')
+    g.local.get(sum_adr)
+    g.i32.const(sa_len.value * sa_type_alloc_size)
+    g.i32.add()
+    g.local.set(sum_stop)
+
+    # sum = *adr
+    # Stack: [] -> [sum]
+    g.nop(comment='Get the first array value as starting point')
+    g.local.get(sum_adr)
+    g.add_statement(f'{sa_type_mtyp}.load')
+
+    # Since we did the first one, increase adr
+    # adr = adr + sa_type_alloc_size
+    # Stack: [sum] -> [sum]
+    g.local.get(sum_adr)
+    g.i32.const(sa_type_alloc_size)
+    g.i32.add()
+    g.local.set(sum_adr)
+
+    if sa_len.value > 1:
+        with g.loop(params=[sa_type_mtyp], result=sa_type_mtyp):
+            # sum = sum + *adr
+            # Stack: [sum] -> [sum + *adr]
+            g.nop(comment='Add array value')
+            g.local.get(sum_adr)
+            g.add_statement(f'{sa_type_mtyp}.load')
+            sa_type_add_gen(g, {})
+
+            # adr = adr + sa_type_alloc_size
+            # Stack: [sum] -> [sum]
+            g.nop(comment='Calculate address of the next value')
+            g.local.get(sum_adr)
+            g.i32.const(sa_type_alloc_size)
+            g.i32.add()
+            g.local.tee(sum_adr)
+
+            # loop if adr < stop
+            g.nop(comment='Check if address exceeds array bounds')
+            g.local.get(sum_stop)
+            g.i32.lt_u()
+            g.br_if(0)
+    # else: sum x[1] === x => so we don't need to loop
+
+    g.nop(comment=f'Completed sum for {sa_type.name}[{sa_len.value}]')
+    # End result: [sum]

phasm/type3/constraints.py

@@ -3,10 +3,22 @@ This module contains possible constraints generated based on the AST
 
 These need to be resolved before the program can be compiled.
 """
-from typing import Dict, List, Optional, Tuple, Union
+from typing import Any, Dict, Iterable, List, Optional, Tuple, Union
 
 from .. import ourlang, prelude
-from . import placeholders, typeclasses, types
+from .placeholders import PlaceholderForType, Type3OrPlaceholder
+from .routers import NoRouteForTypeException, TypeApplicationRouter
+from .typeclasses import Type3Class
+from .types import (
+    IntType3,
+    Type3,
+    TypeApplication_Nullary,
+    TypeApplication_Struct,
+    TypeApplication_TypeInt,
+    TypeApplication_TypeStar,
+    TypeConstructor_Base,
+    TypeConstructor_Struct,
+)
 
 
 class Error:
@@ -32,20 +44,26 @@ class RequireTypeSubstitutes:
     typing of the program, so this constraint can be updated.
     """
 
-SubstitutionMap = Dict[placeholders.PlaceholderForType, types.Type3]
+SubstitutionMap = Dict[PlaceholderForType, Type3]
 
 NewConstraintList = List['ConstraintBase']
 
 CheckResult = Union[None, SubstitutionMap, Error, NewConstraintList, RequireTypeSubstitutes]
 
-HumanReadableRet = Tuple[str, Dict[str, Union[str, ourlang.Expression, types.Type3, placeholders.PlaceholderForType]]]
+HumanReadableRet = Tuple[str, Dict[str, Union[None, int, str, ourlang.Expression, Type3, PlaceholderForType]]]
 
 class Context:
     """
     Context for constraints
     """
 
-    __slots__ = ()
+    __slots__ = ('type_class_instances_existing', )
+
+    # Constraint_TypeClassInstanceExists
+    type_class_instances_existing: set[tuple[Type3Class, tuple[Union[Type3, TypeConstructor_Base[Any], TypeConstructor_Struct], ...]]]
+
+    def __init__(self) -> None:
+        self.type_class_instances_existing = set()
 
 class ConstraintBase:
     """
@@ -92,23 +110,23 @@ class SameTypeConstraint(ConstraintBase):
     """
     __slots__ = ('type_list', )
 
-    type_list: List[placeholders.Type3OrPlaceholder]
+    type_list: List[Type3OrPlaceholder]
 
-    def __init__(self, *type_list: placeholders.Type3OrPlaceholder, comment: Optional[str] = None) -> None:
+    def __init__(self, *type_list: Type3OrPlaceholder, comment: Optional[str] = None) -> None:
         super().__init__(comment=comment)
 
         assert len(type_list) > 1
         self.type_list = [*type_list]
 
     def check(self) -> CheckResult:
-        known_types: List[types.Type3] = []
+        known_types: List[Type3] = []
         phft_list = []
         for typ in self.type_list:
-            if isinstance(typ, types.Type3):
+            if isinstance(typ, Type3):
                 known_types.append(typ)
                 continue
 
-            if isinstance(typ, placeholders.PlaceholderForType):
+            if isinstance(typ, PlaceholderForType):
                 if typ.resolve_as is not None:
                     known_types.append(typ.resolve_as)
                 else:
@@ -125,7 +143,7 @@ class SameTypeConstraint(ConstraintBase):
             if ktyp != first_type:
                 return Error(f'{ktyp:s} must be {first_type:s} instead', comment=self.comment)
 
-        if not placeholders:
+        if not phft_list:
             return None
 
         for phft in phft_list:
@@ -150,138 +168,157 @@ class SameTypeConstraint(ConstraintBase):
 
         return f'SameTypeConstraint({args}, comment={repr(self.comment)})'
 
+class SameTypeArgumentConstraint(ConstraintBase):
+    __slots__ = ('tc_var', 'arg_var', )
+
+    tc_var: PlaceholderForType
+    arg_var: PlaceholderForType
+
+    def __init__(self, tc_var: PlaceholderForType, arg_var: PlaceholderForType, *, comment: str) -> None:
+        super().__init__(comment=comment)
+
+        self.tc_var = tc_var
+        self.arg_var = arg_var
+
+    def check(self) -> CheckResult:
+        if self.tc_var.resolve_as is None or self.arg_var.resolve_as is None:
+            return RequireTypeSubstitutes()
+
+        tc_typ = self.tc_var.resolve_as
+        arg_typ = self.arg_var.resolve_as
+
+        if isinstance(tc_typ.application, TypeApplication_Nullary):
+            return Error(f'{tc_typ:s} must be a constructed type instead')
+
+        if isinstance(tc_typ.application, TypeApplication_TypeStar):
+            # Sure, it's a constructed type. But it's like a struct,
+            # though without the way to implement type classes
+            # Presumably, doing a naked `foo :: t a -> a`
+            # doesn't work since you don't have any info on t
+            # So we can let the MustImplementTypeClassConstraint handle it.
+            return None
+
+        # FIXME: This feels sketchy. Shouldn't the type variable
+        # have the exact same number as arguments?
+        if isinstance(tc_typ.application, TypeApplication_TypeInt):
+            if tc_typ.application.arguments[0] == arg_typ:
+                return None
+
+            return Error(f'{tc_typ.application.arguments[0]:s} must be {arg_typ:s} instead')
+
+        raise NotImplementedError(tc_typ, arg_typ)
+
 class TupleMatchConstraint(ConstraintBase):
-    def __init__(self, exp_type: placeholders.Type3OrPlaceholder, args: List[placeholders.Type3OrPlaceholder], comment: str):
+    __slots__ = ('exp_type', 'args', )
+
+    exp_type: Type3OrPlaceholder
+    args: list[Type3OrPlaceholder]
+
+    def __init__(self, exp_type: Type3OrPlaceholder, args: Iterable[Type3OrPlaceholder], comment: str):
         super().__init__(comment=comment)
 
         self.exp_type = exp_type
         self.args = list(args)
 
+    def _generate_static_array(self, sa_args: tuple[Type3, IntType3]) -> CheckResult:
+        sa_type, sa_len = sa_args
+
+        if sa_len.value != len(self.args):
+            return Error('Mismatch between applied types argument count', comment=self.comment)
+
+        return [
+            SameTypeConstraint(arg, sa_type)
+            for arg in self.args
+        ]
+
+    def _generate_tuple(self, tp_args: tuple[Type3, ...]) -> CheckResult:
+        if len(tp_args) != len(self.args):
+            return Error('Mismatch between applied types argument count', comment=self.comment)
+
+        return [
+            SameTypeConstraint(arg, oth_arg)
+            for arg, oth_arg in zip(self.args, tp_args, strict=True)
+        ]
+
+    GENERATE_ROUTER = TypeApplicationRouter['TupleMatchConstraint', CheckResult]()
+    GENERATE_ROUTER.add(prelude.static_array, _generate_static_array)
+    GENERATE_ROUTER.add(prelude.tuple_, _generate_tuple)
+
     def check(self) -> CheckResult:
         exp_type = self.exp_type
-        if isinstance(exp_type, placeholders.PlaceholderForType):
+        if isinstance(exp_type, PlaceholderForType):
             if exp_type.resolve_as is None:
                 return RequireTypeSubstitutes()
 
             exp_type = exp_type.resolve_as
 
-        assert isinstance(exp_type, types.Type3)
+        try:
-
+            return self.__class__.GENERATE_ROUTER(self, exp_type)
-        sa_args = prelude.static_array.did_construct(exp_type)
+        except NoRouteForTypeException:
-        if sa_args is not None:
+            raise NotImplementedError(exp_type)
-            sa_type, sa_len = sa_args
-
-            if sa_len.value != len(self.args):
-                return Error('Mismatch between applied types argument count', comment=self.comment)
-
-            return [
-                SameTypeConstraint(arg, sa_type)
-                for arg in self.args
-            ]
-
-        tp_args = prelude.tuple_.did_construct(exp_type)
-        if tp_args is not None:
-            if len(tp_args) != len(self.args):
-                return Error('Mismatch between applied types argument count', comment=self.comment)
-
-            return [
-                SameTypeConstraint(arg, oth_arg)
-                for arg, oth_arg in zip(self.args, tp_args, strict=True)
-            ]
-
-        raise NotImplementedError(exp_type)
-
-class CastableConstraint(ConstraintBase):
-    """
-    A type can be cast to another type
-    """
-    __slots__ = ('from_type3', 'to_type3', )
-
-    from_type3: placeholders.Type3OrPlaceholder
-    to_type3: placeholders.Type3OrPlaceholder
-
-    def __init__(self, from_type3: placeholders.Type3OrPlaceholder, to_type3: placeholders.Type3OrPlaceholder, comment: Optional[str] = None) -> None:
-        super().__init__(comment=comment)
-
-        self.from_type3 = from_type3
-        self.to_type3 = to_type3
-
-    def check(self) -> CheckResult:
-        ftyp = self.from_type3
-        if isinstance(ftyp, placeholders.PlaceholderForType) and ftyp.resolve_as is not None:
-            ftyp = ftyp.resolve_as
-
-        ttyp = self.to_type3
-        if isinstance(ttyp, placeholders.PlaceholderForType) and ttyp.resolve_as is not None:
-            ttyp = ttyp.resolve_as
-
-        if isinstance(ftyp, placeholders.PlaceholderForType) or isinstance(ttyp, placeholders.PlaceholderForType):
-            return RequireTypeSubstitutes()
-
-        if ftyp is prelude.u8 and ttyp is prelude.u32:
-            return None
-
-        return Error(f'Cannot cast {ftyp.name} to {ttyp.name}')
-
-    def human_readable(self) -> HumanReadableRet:
-        return (
-            '{to_type3}({from_type3})',
-            {
-                'to_type3': self.to_type3,
-                'from_type3': self.from_type3,
-            },
-        )
-
-    def __repr__(self) -> str:
-        return f'CastableConstraint({repr(self.from_type3)}, {repr(self.to_type3)}, comment={repr(self.comment)})'
 
 class MustImplementTypeClassConstraint(ConstraintBase):
     """
     A type must implement a given type class
     """
-    __slots__ = ('type_class3', 'type3', )
+    __slots__ = ('context', 'type_class3', 'types', )
 
-    type_class3: Union[str, typeclasses.Type3Class]
+    context: Context
-    type3: placeholders.Type3OrPlaceholder
+    type_class3: Type3Class
+    types: list[Type3OrPlaceholder]
 
-    DATA = {
+    def __init__(self, context: Context, type_class3: Type3Class, typ_list: list[Type3OrPlaceholder], comment: Optional[str] = None) -> None:
-        'bytes': {'Foldable'},
-    }
-
-    def __init__(self, type_class3: Union[str, typeclasses.Type3Class], type3: placeholders.Type3OrPlaceholder, comment: Optional[str] = None) -> None:
         super().__init__(comment=comment)
 
+        self.context = context
         self.type_class3 = type_class3
-        self.type3 = type3
+        self.types = typ_list
 
     def check(self) -> CheckResult:
-        typ = self.type3
+        typ_list: list[Type3 | TypeConstructor_Base[Any] | TypeConstructor_Struct] = []
-        if isinstance(typ, placeholders.PlaceholderForType) and typ.resolve_as is not None:
+        for typ in self.types:
-            typ = typ.resolve_as
+            if isinstance(typ, PlaceholderForType) and typ.resolve_as is not None:
+                typ = typ.resolve_as
 
-        if isinstance(typ, placeholders.PlaceholderForType):
+            if isinstance(typ, PlaceholderForType):
-            return RequireTypeSubstitutes()
+                return RequireTypeSubstitutes()
 
-        if isinstance(self.type_class3, typeclasses.Type3Class):
+            if isinstance(typ.application, (TypeApplication_Nullary, TypeApplication_Struct, )):
-            if self.type_class3 in typ.classes:
+                typ_list.append(typ)
-                return None
+                continue
-        else:
-            if self.type_class3 in self.__class__.DATA.get(typ.name, set()):
-                return None
 
-        return Error(f'{typ.name} does not implement the {self.type_class3} type class')
+            if isinstance(typ.application, (TypeApplication_TypeInt, TypeApplication_TypeStar)):
+                typ_list.append(typ.application.constructor)
+                continue
+
+            raise NotImplementedError(typ, typ.application)
+
+        assert len(typ_list) == len(self.types)
+
+        key = (self.type_class3, tuple(typ_list), )
+        if key in self.context.type_class_instances_existing:
+            return None
+
+        typ_cls_name = self.type_class3 if isinstance(self.type_class3, str) else self.type_class3.name
+        typ_name_list = ' '.join(x.name for x in typ_list)
+        return Error(f'Missing type class instantation: {typ_cls_name} {typ_name_list}')
 
     def human_readable(self) -> HumanReadableRet:
+        keys = {
+            f'type{idx}': typ
+            for idx, typ in enumerate(self.types)
+        }
+
         return (
-            '{type3} derives {type_class3}',
+            'Exists instance {type_class3} ' + ' '.join(f'{{{x}}}' for x in keys),
             {
                 'type_class3': str(self.type_class3),
-                'type3': self.type3,
+                **keys,
             },
         )
 
     def __repr__(self) -> str:
-        return f'MustImplementTypeClassConstraint({repr(self.type_class3)}, {repr(self.type3)}, comment={repr(self.comment)})'
+        return f'MustImplementTypeClassConstraint({repr(self.type_class3)}, {repr(self.types)}, comment={repr(self.comment)})'
 
 class LiteralFitsConstraint(ConstraintBase):
     """
@@ -289,12 +326,12 @@ class LiteralFitsConstraint(ConstraintBase):
     """
     __slots__ = ('type3', 'literal', )
 
-    type3: placeholders.Type3OrPlaceholder
+    type3: Type3OrPlaceholder
     literal: Union[ourlang.ConstantPrimitive, ourlang.ConstantBytes, ourlang.ConstantTuple, ourlang.ConstantStruct]
 
     def __init__(
             self,
-            type3: placeholders.Type3OrPlaceholder,
+            type3: Type3OrPlaceholder,
             literal: Union[ourlang.ConstantPrimitive, ourlang.ConstantBytes, ourlang.ConstantTuple, ourlang.ConstantStruct],
             comment: Optional[str] = None,
         ) -> None:
@@ -303,6 +340,91 @@ class LiteralFitsConstraint(ConstraintBase):
         self.type3 = type3
         self.literal = literal
 
+    def _generate_static_array(self, sa_args: tuple[Type3, IntType3]) -> CheckResult:
+        if not isinstance(self.literal, ourlang.ConstantTuple):
+            return Error('Must be tuple', comment=self.comment)
+
+        sa_type, sa_len = sa_args
+
+        if sa_len.value != len(self.literal.value):
+            return Error('Member count mismatch', comment=self.comment)
+
+        res: list[ConstraintBase] = []
+
+        res.extend(
+            LiteralFitsConstraint(sa_type, y)
+            for y in self.literal.value
+        )
+
+        # Generate placeholders so each Literal expression
+        # gets updated when we figure out the type of the
+        # expression the literal is used in
+        res.extend(
+            SameTypeConstraint(sa_type, PlaceholderForType([y]))
+            for y in self.literal.value
+        )
+
+        return res
+
+    def _generate_struct(self, st_args: tuple[tuple[str, Type3], ...]) -> CheckResult:
+        if not isinstance(self.literal, ourlang.ConstantStruct):
+            return Error('Must be struct')
+
+        if len(st_args) != len(self.literal.value):
+            return Error('Struct element count mismatch')
+
+        res: list[ConstraintBase] = []
+
+        res.extend(
+            LiteralFitsConstraint(x, y)
+            for (_, x), y in zip(st_args, self.literal.value, strict=True)
+        )
+
+        # Generate placeholders so each Literal expression
+        # gets updated when we figure out the type of the
+        # expression the literal is used in
+        res.extend(
+            SameTypeConstraint(x_t, PlaceholderForType([y]), comment=f'{self.literal.struct_type3.name}.{x_n}')
+            for (x_n, x_t, ), y in zip(st_args, self.literal.value, strict=True)
+        )
+
+        res.append(SameTypeConstraint(
+            self.literal.struct_type3,
+            self.type3,
+            comment='Struct types must match',
+        ))
+
+        return res
+
+    def _generate_tuple(self, tp_args: tuple[Type3, ...]) -> CheckResult:
+        if not isinstance(self.literal, ourlang.ConstantTuple):
+            return Error('Must be tuple', comment=self.comment)
+
+        if len(tp_args) != len(self.literal.value):
+            return Error('Tuple element count mismatch', comment=self.comment)
+
+        res: list[ConstraintBase] = []
+
+        res.extend(
+            LiteralFitsConstraint(x, y)
+            for x, y in zip(tp_args, self.literal.value, strict=True)
+        )
+
+        # Generate placeholders so each Literal expression
+        # gets updated when we figure out the type of the
+        # expression the literal is used in
+        res.extend(
+            SameTypeConstraint(x, PlaceholderForType([y]))
+            for x, y in zip(tp_args, self.literal.value, strict=True)
+        )
+
+        return res
+
+    GENERATE_ROUTER = TypeApplicationRouter['LiteralFitsConstraint', CheckResult]()
+    GENERATE_ROUTER.add(prelude.static_array, _generate_static_array)
+    GENERATE_ROUTER.add(prelude.struct, _generate_struct)
+    GENERATE_ROUTER.add(prelude.tuple_, _generate_tuple)
+
     def check(self) -> CheckResult:
         int_table: Dict[str, Tuple[int, bool]] = {
             'u8': (1, False),
@@ -318,7 +440,7 @@ class LiteralFitsConstraint(ConstraintBase):
             'f64': None,
         }
 
-        if isinstance(self.type3, placeholders.PlaceholderForType):
+        if isinstance(self.type3, PlaceholderForType):
             if self.type3.resolve_as is None:
                 return RequireTypeSubstitutes()
 
@@ -353,80 +475,12 @@ class LiteralFitsConstraint(ConstraintBase):
 
             return Error('Must be bytes', comment=self.comment) # FIXME: Add line information
 
-        res: NewConstraintList
+        exp_type = self.type3
 
-        assert isinstance(self.type3, types.Type3)
+        try:
-
+            return self.__class__.GENERATE_ROUTER(self, exp_type)
-        tp_args = prelude.tuple_.did_construct(self.type3)
+        except NoRouteForTypeException:
-        if tp_args is not None:
+            raise NotImplementedError(exp_type)
-                if not isinstance(self.literal, ourlang.ConstantTuple):
-                    return Error('Must be tuple', comment=self.comment)
-
-                if len(tp_args) != len(self.literal.value):
-                    return Error('Tuple element count mismatch', comment=self.comment)
-
-                res = []
-
-                res.extend(
-                    LiteralFitsConstraint(x, y)
-                    for x, y in zip(tp_args, self.literal.value, strict=True)
-                )
-                res.extend(
-                    SameTypeConstraint(x, y.type3)
-                    for x, y in zip(tp_args, self.literal.value, strict=True)
-                )
-
-                return res
-
-        sa_args = prelude.static_array.did_construct(self.type3)
-        if sa_args is not None:
-                if not isinstance(self.literal, ourlang.ConstantTuple):
-                    return Error('Must be tuple', comment=self.comment)
-
-                sa_type, sa_len = sa_args
-
-                if sa_len.value != len(self.literal.value):
-                    return Error('Member count mismatch', comment=self.comment)
-
-                res = []
-
-                res.extend(
-                    LiteralFitsConstraint(sa_type, y)
-                    for y in self.literal.value
-                )
-                res.extend(
-                    SameTypeConstraint(sa_type, y.type3)
-                    for y in self.literal.value
-                )
-
-                return res
-
-        st_args = prelude.struct.did_construct(self.type3)
-        if st_args is not None:
-            if not isinstance(self.literal, ourlang.ConstantStruct):
-                return Error('Must be struct')
-
-            if self.literal.struct_name != self.type3.name:
-                return Error('Struct mismatch')
-
-
-            if len(st_args) != len(self.literal.value):
-                return Error('Struct element count mismatch')
-
-            res = []
-
-            res.extend(
-                LiteralFitsConstraint(x, y)
-                for x, y in zip(st_args.values(), self.literal.value, strict=True)
-            )
-            res.extend(
-                SameTypeConstraint(x_t, y.type3, comment=f'{self.literal.struct_name}.{x_n}')
-                for (x_n, x_t, ), y in zip(st_args.items(), self.literal.value, strict=True)
-            )
-
-            return res
-
-        raise NotImplementedError(self.type3, self.literal)
 
     def human_readable(self) -> HumanReadableRet:
         return (
@@ -444,83 +498,85 @@ class CanBeSubscriptedConstraint(ConstraintBase):
     """
     A value that is subscipted, i.e. a[0] (tuple) or a[b] (static array)
     """
-    __slots__ = ('ret_type3', 'type3', 'index', 'index_type3', )
+    __slots__ = ('ret_type3', 'type3', 'index_type3', 'index_const', )
 
-    ret_type3: placeholders.Type3OrPlaceholder
+    ret_type3: PlaceholderForType
-    type3: placeholders.Type3OrPlaceholder
+    type3: PlaceholderForType
-    index: ourlang.Expression
+    index_type3: PlaceholderForType
-    index_type3: placeholders.Type3OrPlaceholder
+    index_const: int | None
 
-    def __init__(self, ret_type3: placeholders.Type3OrPlaceholder, type3: placeholders.Type3OrPlaceholder, index: ourlang.Expression, comment: Optional[str] = None) -> None:
+    def __init__(
+            self,
+            ret_type3: PlaceholderForType,
+            type3: PlaceholderForType,
+            index_type3: PlaceholderForType,
+            index_const: int | None,
+            comment: Optional[str] = None,
+        ) -> None:
         super().__init__(comment=comment)
 
         self.ret_type3 = ret_type3
         self.type3 = type3
-        self.index = index
+        self.index_type3 = index_type3
-        self.index_type3 = index.type3
+        self.index_const = index_const
 
-    def check(self) -> CheckResult:
+    def _generate_bytes(self) -> CheckResult:
-        exp_type = self.type3
+        return [
-        if isinstance(exp_type, placeholders.PlaceholderForType):
+            SameTypeConstraint(prelude.u32, self.index_type3, comment='([]) :: bytes -> u32 -> u8'),
-            if exp_type.resolve_as is None:
+            SameTypeConstraint(prelude.u8, self.ret_type3, comment='([]) :: bytes -> u32 -> u8'),
-                return RequireTypeSubstitutes()
+        ]
 
-            exp_type = exp_type.resolve_as
+    def _generate_static_array(self, sa_args: tuple[Type3, IntType3]) -> CheckResult:
+        sa_type, sa_len = sa_args
 
-        assert isinstance(exp_type, types.Type3)
+        if self.index_const is not None and (self.index_const < 0 or sa_len.value <= self.index_const):
+            return Error('Tuple index out of range')
 
-        sa_args = prelude.static_array.did_construct(exp_type)
+        return [
-        if sa_args is not None:
+            SameTypeConstraint(prelude.u32, self.index_type3, comment='([]) :: Subscriptable a => a b -> u32 -> b'),
-                sa_type, sa_len = sa_args
+            SameTypeConstraint(sa_type, self.ret_type3, comment='([]) :: Subscriptable a => a b -> u32 -> b'),
-
+        ]
-                result: List[ConstraintBase] = [
-                    SameTypeConstraint(prelude.u32, self.index_type3, comment='([]) :: Subscriptable a => a b -> u32 -> b'),
-                    SameTypeConstraint(sa_type, self.ret_type3, comment='([]) :: Subscriptable a => a b -> u32 -> b'),
-                ]
-
-                if isinstance(self.index, ourlang.ConstantPrimitive):
-                    assert isinstance(self.index.value, int)
-
-                    if self.index.value < 0 or sa_len.value <= self.index.value:
-                        return Error('Tuple index out of range')
-
-                return result
 
+    def _generate_tuple(self, tp_args: tuple[Type3, ...]) -> CheckResult:
         # We special case tuples to allow for ease of use to the programmer
         # e.g. rather than having to do `fst a` and `snd a` and only have to-sized tuples
         # we use a[0] and a[1] and allow for a[2] and on.
-        tp_args = prelude.tuple_.did_construct(exp_type)
-        if tp_args is not None:
-                if not isinstance(self.index, ourlang.ConstantPrimitive):
-                    return Error('Must index with literal')
 
-                if not isinstance(self.index.value, int):
+        if self.index_const is None:
-                    return Error('Must index with integer literal')
+            return Error('Must index with integer literal')
 
-                if self.index.value < 0 or len(tp_args) <= self.index.value:
+        if self.index_const < 0 or len(tp_args) <= self.index_const:
-                    return Error('Tuple index out of range')
+            return Error('Tuple index out of range')
 
-                return [
+        return [
-                    SameTypeConstraint(prelude.u32, self.index_type3, comment=f'Tuple subscript index {self.index.value}'),
+            SameTypeConstraint(prelude.u32, self.index_type3, comment='([]) :: Subscriptable a => a b -> u32 -> b'),
-                    SameTypeConstraint(tp_args[self.index.value], self.ret_type3, comment=f'Tuple subscript index {self.index.value}'),
+            SameTypeConstraint(tp_args[self.index_const], self.ret_type3, comment=f'Tuple subscript index {self.index_const}'),
-                ]
+        ]
 
-        if exp_type is prelude.bytes_:
+    GENERATE_ROUTER = TypeApplicationRouter['CanBeSubscriptedConstraint', CheckResult]()
-            return [
+    GENERATE_ROUTER.add_n(prelude.bytes_, _generate_bytes)
-                SameTypeConstraint(prelude.u32, self.index_type3, comment='([]) :: bytes -> u32 -> u8'),
+    GENERATE_ROUTER.add(prelude.static_array, _generate_static_array)
-                SameTypeConstraint(prelude.u8, self.ret_type3, comment='([]) :: bytes -> u32 -> u8'),
+    GENERATE_ROUTER.add(prelude.tuple_, _generate_tuple)
-            ]
 
-        return Error(f'{exp_type.name} cannot be subscripted')
+    def check(self) -> CheckResult:
+        if self.type3.resolve_as is None:
+            return RequireTypeSubstitutes()
+
+        exp_type = self.type3.resolve_as
+
+        try:
+            return self.__class__.GENERATE_ROUTER(self, exp_type)
+        except NoRouteForTypeException:
+            return Error(f'{exp_type.name} cannot be subscripted')
 
     def human_readable(self) -> HumanReadableRet:
         return (
             '{type3}[{index}]',
             {
                 'type3': self.type3,
-                'index': self.index,
+                'index': self.index_type3 if self.index_const is None else self.index_const,
             },
         )
 
     def __repr__(self) -> str:
-        return f'CanBeSubscriptedConstraint({repr(self.type3)}, {repr(self.index)}, comment={repr(self.comment)})'
+        return f'CanBeSubscriptedConstraint({self.ret_type3!r}, {self.type3!r}, {self.index_type3!r}, {self.index_const!r}, comment={repr(self.comment)})'

phasm/type3/constraintsgenerator.py

@@ -6,109 +6,180 @@ The constraints solver can then try to resolve all constraints.
 from typing import Generator, List
 
 from .. import ourlang, prelude
-from . import functions as functions
-from . import placeholders as placeholders
-from . import typeclasses as typeclasses
-from . import types as type3types
 from .constraints import (
     CanBeSubscriptedConstraint,
-    CastableConstraint,
     ConstraintBase,
     Context,
     LiteralFitsConstraint,
     MustImplementTypeClassConstraint,
+    SameTypeArgumentConstraint,
     SameTypeConstraint,
     TupleMatchConstraint,
 )
+from .functions import (
+    Constraint_TypeClassInstanceExists,
+    FunctionSignature,
+    TypeVariable,
+    TypeVariableApplication_Unary,
+)
+from .placeholders import PlaceholderForType
+from .types import Type3, TypeApplication_Struct
 
 ConstraintGenerator = Generator[ConstraintBase, None, None]
 
 def phasm_type3_generate_constraints(inp: ourlang.Module) -> List[ConstraintBase]:
     ctx = Context()
+    ctx.type_class_instances_existing.update(prelude.PRELUDE_TYPE_CLASS_INSTANCES_EXISTING)
 
     return [*module(ctx, inp)]
 
-def constant(ctx: Context, inp: ourlang.Constant) -> ConstraintGenerator:
+def constant(ctx: Context, inp: ourlang.Constant, phft: PlaceholderForType) -> ConstraintGenerator:
     if isinstance(inp, (ourlang.ConstantPrimitive, ourlang.ConstantBytes, ourlang.ConstantTuple, ourlang.ConstantStruct)):
         yield LiteralFitsConstraint(
-            inp.type3, inp,
+            phft, inp,
             comment='The given literal must fit the expected type'
         )
         return
 
     raise NotImplementedError(constant, inp)
 
-def expression(ctx: Context, inp: ourlang.Expression) -> ConstraintGenerator:
+def expression_binary_op(ctx: Context, inp: ourlang.BinaryOp, phft: PlaceholderForType) -> ConstraintGenerator:
+    return _expression_function_call(
+        ctx,
+        f'({inp.operator.name})',
+        inp.operator.signature,
+        [inp.left, inp.right],
+        inp,
+        phft,
+    )
+
+def expression_function_call(ctx: Context, inp: ourlang.FunctionCall, phft: PlaceholderForType) -> ConstraintGenerator:
+    return _expression_function_call(
+            ctx,
+            inp.function.name,
+            inp.function.signature,
+            inp.arguments,
+            inp,
+            phft,
+        )
+
+def _expression_function_call(
+        ctx: Context,
+        func_name: str,
+        signature: FunctionSignature,
+        arguments: list[ourlang.Expression],
+        return_expr: ourlang.Expression,
+        return_phft: PlaceholderForType,
+    ) -> ConstraintGenerator:
+    """
+    Generates all type-level constraints for a function call.
+
+    A Binary operator functions pretty much the same as a function call
+    with two arguments - it's only a syntactic difference.
+    """
+    # First create placeholders for all arguments, and generate their constraints
+    arg_placeholders = {
+        arg_expr: PlaceholderForType([arg_expr])
+        for arg_expr in arguments
+    }
+    arg_placeholders[return_expr] = return_phft
+
+    for call_arg in arguments:
+        yield from expression(ctx, call_arg, arg_placeholders[call_arg])
+
+    # Then generate placeholders the function signature
+    # and apply constraints that the function requires
+    # Skip any fully reference types
+    # Making this a map ensures that if a function signature has
+    # the same type on multiple arguments, we only get one
+    # placeholder here. These don't need to update anything once
+    # subsituted - that's done by arg_placeholders.
+    type_var_map = {
+        x: PlaceholderForType([])
+        for x in signature.args
+        if isinstance(x, TypeVariable)
+    }
+
+    for constraint in signature.context.constraints:
+        if isinstance(constraint, Constraint_TypeClassInstanceExists):
+            yield MustImplementTypeClassConstraint(
+                ctx,
+                constraint.type_class3,
+                [type_var_map[x] for x in constraint.types],
+            )
+            continue
+
+        raise NotImplementedError(constraint)
+
+    # If some of the function arguments are type constructors,
+    # we need to deal with those separately.
+    # That is, given `foo :: t a -> a` we need to ensure
+    # that both a's are the same.
+    for sig_arg in signature.args:
+        if isinstance(sig_arg, Type3):
+            # Not a type variable at all
+            continue
+
+        if sig_arg.application.constructor is None:
+            # Not a type variable for a type constructor
+            continue
+
+        if not isinstance(sig_arg.application, TypeVariableApplication_Unary):
+            raise NotImplementedError(sig_arg.application)
+
+        assert sig_arg.application.arguments in type_var_map  # When does this happen?
+
+        yield SameTypeArgumentConstraint(
+            type_var_map[sig_arg],
+            type_var_map[sig_arg.application.arguments],
+            comment=f'Ensure `{sig_arg.application.arguments.name}` matches in {signature}',
+        )
+
+    # Lastly, tie the signature and expression together
+    for arg_no, (sig_part, arg_expr) in enumerate(zip(signature.args, arguments + [return_expr], strict=True)):
+        if arg_no == len(arguments):
+            comment = f'The type of a function call to {func_name} is the same as the type that the function returns'
+        else:
+            comment = f'The type of the value passed to argument {arg_no} of function {func_name} should match the type of that argument'
+
+        if isinstance(sig_part, TypeVariable):
+            yield SameTypeConstraint(type_var_map[sig_part], arg_placeholders[arg_expr], comment=comment)
+            continue
+
+        if isinstance(sig_part, Type3):
+            yield SameTypeConstraint(sig_part, arg_placeholders[arg_expr], comment=comment)
+            continue
+
+        raise NotImplementedError(sig_part)
+    return
+
+def expression(ctx: Context, inp: ourlang.Expression, phft: PlaceholderForType) -> ConstraintGenerator:
     if isinstance(inp, ourlang.Constant):
-        yield from constant(ctx, inp)
+        yield from constant(ctx, inp, phft)
         return
 
     if isinstance(inp, ourlang.VariableReference):
-        yield SameTypeConstraint(inp.variable.type3, inp.type3,
+        yield SameTypeConstraint(inp.variable.type3, phft,
             comment=f'typeOf("{inp.variable.name}") == typeOf({inp.variable.name})')
         return
 
-    if isinstance(inp, ourlang.UnaryOp):
+    if isinstance(inp, ourlang.BinaryOp):
-        if 'cast' == inp.operator:
+        yield from expression_binary_op(ctx, inp, phft)
-            yield from expression(ctx, inp.right)
+        return
-            yield CastableConstraint(inp.right.type3, inp.type3)
-            return
 
-        raise NotImplementedError(expression, inp, inp.operator)
+    if isinstance(inp, ourlang.FunctionCall):
-
+        yield from expression_function_call(ctx, inp, phft)
-    if isinstance(inp, ourlang.BinaryOp) or isinstance(inp, ourlang.FunctionCall):
-        signature = inp.operator.signature if isinstance(inp, ourlang.BinaryOp) else inp.function.signature
-        arguments = [inp.left, inp.right] if isinstance(inp, ourlang.BinaryOp) else inp.arguments
-
-        func_name = f'({inp.operator.name})' if isinstance(inp, ourlang.BinaryOp) else inp.function.name
-
-        type_var_map = {
-            x: placeholders.PlaceholderForType([])
-            for x in signature.args
-            if isinstance(x, functions.TypeVariable)
-        }
-
-        for call_arg in arguments:
-            yield from expression(ctx, call_arg)
-
-        for type_var, constraint_list in signature.context.constraints.items():
-            assert type_var in type_var_map # When can this happen?
-
-            for constraint in constraint_list:
-                if isinstance(constraint, functions.TypeVariableConstraint_TypeHasTypeClass):
-                    yield MustImplementTypeClassConstraint(
-                        constraint.type_class3,
-                        type_var_map[type_var],
-                    )
-                    continue
-
-                raise NotImplementedError(constraint)
-
-        for arg_no, (sig_part, arg_expr) in enumerate(zip(signature.args, arguments + [inp], strict=True)):
-            if arg_no == len(arguments):
-                comment = f'The type of a function call to {func_name} is the same as the type that the function returns'
-            else:
-                comment = f'The type of the value passed to argument {arg_no} of function {func_name} should match the type of that argument'
-
-            if isinstance(sig_part, functions.TypeVariable):
-                yield SameTypeConstraint(type_var_map[sig_part], arg_expr.type3, comment=comment)
-                continue
-
-            if isinstance(sig_part, type3types.Type3):
-                yield SameTypeConstraint(sig_part, arg_expr.type3, comment=comment)
-                continue
-
-            raise NotImplementedError(sig_part)
         return
 
     if isinstance(inp, ourlang.TupleInstantiation):
         r_type = []
         for arg in inp.elements:
-            yield from expression(ctx, arg)
+            arg_phft = PlaceholderForType([arg])
-            r_type.append(arg.type3)
+            yield from expression(ctx, arg, arg_phft)
+            r_type.append(arg_phft)
 
         yield TupleMatchConstraint(
-            inp.type3,
+            phft,
             r_type,
             comment='The type of a tuple is a combination of its members'
         )
@@ -116,44 +187,44 @@ def expression(ctx: Context, inp: ourlang.Expression) -> ConstraintGenerator:
         return
 
     if isinstance(inp, ourlang.Subscript):
-        yield from expression(ctx, inp.varref)
+        varref_phft = PlaceholderForType([inp.varref])
-        yield from expression(ctx, inp.index)
+        index_phft = PlaceholderForType([inp.index])
 
-        yield CanBeSubscriptedConstraint(inp.type3, inp.varref.type3, inp.index)
+        yield from expression(ctx, inp.varref, varref_phft)
+        yield from expression(ctx, inp.index, index_phft)
+
+        if isinstance(inp.index, ourlang.ConstantPrimitive) and isinstance(inp.index.value, int):
+            yield CanBeSubscriptedConstraint(phft, varref_phft, index_phft, inp.index.value)
+        else:
+            yield CanBeSubscriptedConstraint(phft, varref_phft, index_phft, None)
         return
 
     if isinstance(inp, ourlang.AccessStructMember):
-        assert isinstance(inp.struct_type3, type3types.Type3)  # When does this happen?
+        assert isinstance(inp.struct_type3.application, TypeApplication_Struct)  # FIXME: See test_struct.py::test_struct_not_accessible
-        st_args = prelude.struct.did_construct(inp.struct_type3)
-        assert st_args is not None  # When does this happen?
 
-        yield from expression(ctx, inp.varref)
+        mem_typ = dict(inp.struct_type3.application.arguments)[inp.member]
-        yield SameTypeConstraint(st_args[inp.member], inp.type3,
+
+        yield from expression(ctx, inp.varref, PlaceholderForType([inp.varref]))  # TODO
+        yield SameTypeConstraint(mem_typ, phft,
             comment=f'The type of a struct member reference is the same as the type of struct member {inp.struct_type3.name}.{inp.member}')
         return
 
-    if isinstance(inp, ourlang.Fold):
-        yield from expression(ctx, inp.base)
-        yield from expression(ctx, inp.iter)
-
-        yield SameTypeConstraint(inp.func.posonlyargs[0].type3, inp.func.returns_type3, inp.base.type3, inp.type3,
-            comment='foldl :: Foldable t => (b -> a -> b) -> b -> t a -> b')
-        yield MustImplementTypeClassConstraint('Foldable', inp.iter.type3)
-
-        return
-
     raise NotImplementedError(expression, inp)
 
 def statement_return(ctx: Context, fun: ourlang.Function, inp: ourlang.StatementReturn) -> ConstraintGenerator:
-    yield from expression(ctx, inp.value)
+    phft = PlaceholderForType([inp.value])
 
-    yield SameTypeConstraint(fun.returns_type3, inp.value.type3,
+    yield from expression(ctx, inp.value, phft)
+
+    yield SameTypeConstraint(fun.returns_type3, phft,
         comment=f'The type of the value returned from function {fun.name} should match its return type')
 
 def statement_if(ctx: Context, fun: ourlang.Function, inp: ourlang.StatementIf) -> ConstraintGenerator:
-    yield from expression(ctx, inp.test)
+    test_phft = PlaceholderForType([inp.test])
 
-    yield SameTypeConstraint(inp.test.type3, prelude.bool_,
+    yield from expression(ctx, inp.test, test_phft)
+
+    yield SameTypeConstraint(test_phft, prelude.bool_,
         comment='Must pass a boolean expression to if')
 
     for stmt in inp.statements:
@@ -183,8 +254,10 @@ def function(ctx: Context, inp: ourlang.Function) -> ConstraintGenerator:
         yield from statement(ctx, inp, stmt)
 
 def module_constant_def(ctx: Context, inp: ourlang.ModuleConstantDef) -> ConstraintGenerator:
-    yield from constant(ctx, inp.constant)
+    phft = PlaceholderForType([inp.constant])
-    yield SameTypeConstraint(inp.type3, inp.constant.type3,
+
+    yield from constant(ctx, inp.constant, phft)
+    yield SameTypeConstraint(inp.type3, phft,
         comment=f'The type of the value for module constant definition {inp.name} should match the type of that constant')
 
 def module(ctx: Context, inp: ourlang.Module) -> ConstraintGenerator:

phasm/type3/entry.py

@@ -115,8 +115,6 @@ def phasm_type3(inp: ourlang.Module, verbose: bool = False) -> None:
     # FIXME: This doesn't work with e.g. `:: [a] -> a`, as the placeholder is inside a type
     for plh, typ in placeholder_substitutes.items():
         for expr in plh.update_on_substitution:
-            assert expr.type3 is plh
-
             expr.type3 = typ
 
 def print_constraint(placeholder_id_map: Dict[int, str], constraint: ConstraintBase) -> None:

phasm/type3/functions.py

@@ -1,10 +1,36 @@
-from typing import TYPE_CHECKING, Any, Iterable, List, Union
+from typing import TYPE_CHECKING, Any, Hashable, Iterable, List, Union
 
 if TYPE_CHECKING:
     from .typeclasses import Type3Class
     from .types import Type3
 
 
+class TypeVariableApplication_Base[T: Hashable, S: Hashable]:
+    """
+    Records the constructor and arguments used to create this type.
+
+    Nullary types, or types of kind *, have both arguments set to None.
+    """
+    constructor: T
+    arguments: S
+
+    def __init__(self, constructor: T, arguments: S) -> None:
+        self.constructor = constructor
+        self.arguments = arguments
+
+    def __hash__(self) -> int:
+        return hash((self.constructor, self.arguments, ))
+
+    def __eq__(self, other: Any) -> bool:
+        if not isinstance(other, TypeVariableApplication_Base):
+            raise NotImplementedError
+
+        return (self.constructor == other.constructor  # type: ignore[no-any-return]
+            and self.arguments == other.arguments)
+
+    def __repr__(self) -> str:
+        return f'{self.__class__.__name__}({self.constructor!r}, {self.arguments!r})'
+
 class TypeVariable:
     """
     Types variable are used in function definition.
@@ -14,47 +40,120 @@ class TypeVariable:
     during type checking. These type variables are used solely in the
     function's definition
     """
-    __slots__ = ('letter', )
+    __slots__ = ('name', 'application', )
 
-    letter: str
+    name: str
+    application: TypeVariableApplication_Base[Any, Any]
 
-    def __init__(self, letter: str) -> None:
+    def __init__(self, name: str, application: TypeVariableApplication_Base[Any, Any]) -> None:
-        assert len(letter) == 1, f'{letter} is not a valid type variable'
+        self.name = name
-        self.letter = letter
+        self.application = application
 
     def __hash__(self) -> int:
-        return hash(self.letter)
+        return hash((self.name, self.application, ))
 
     def __eq__(self, other: Any) -> bool:
         if not isinstance(other, TypeVariable):
             raise NotImplementedError
 
-        return self.letter == other.letter
+        return (self.name == other.name
+            and self.application == other.application)
 
     def __repr__(self) -> str:
-        return f'TypeVariable({repr(self.letter)})'
+        return f'TypeVariable({repr(self.name)})'
 
-class TypeVariableConstraintBase:
+class TypeVariableApplication_Nullary(TypeVariableApplication_Base[None, None]):
+    """
+    For the type for this function argument it's not relevant if it was constructed.
+    """
+
+class TypeConstructorVariable:
+    """
+    Types constructor variable are used in function definition.
+
+    They are a lot like TypeVariable, except that they represent a
+    type constructor rather than a type directly.
+
+    For now, we only have type constructor variables for kind
+    * -> *.
+    """
+    __slots__ = ('name', )
+
+    name: str
+
+    def __init__(self, name: str) -> None:
+        self.name = name
+
+    def __hash__(self) -> int:
+        return hash((self.name, ))
+
+    def __eq__(self, other: Any) -> bool:
+        if other is None:
+            return False
+
+        if not isinstance(other, TypeConstructorVariable):
+            raise NotImplementedError
+
+        return (self.name == other.name)
+
+    def __call__(self, tvar: TypeVariable) -> 'TypeVariable':
+        return TypeVariable(
+            self.name + ' ' + tvar.name,
+            TypeVariableApplication_Unary(self, tvar)
+        )
+
+    def __repr__(self) -> str:
+        return f'TypeConstructorVariable({self.name!r})'
+
+class TypeVariableApplication_Unary(TypeVariableApplication_Base[TypeConstructorVariable, TypeVariable]):
+    """
+    The type for this function argument should be constructed from a type constructor.
+
+    And we need to know what construtor that was, since that's the one we support.
+    """
+
+class ConstraintBase:
     __slots__ = ()
 
-class TypeVariableConstraint_TypeHasTypeClass(TypeVariableConstraintBase):
+class Constraint_TypeClassInstanceExists(ConstraintBase):
-    __slots__ = ('type_class3', )
+    __slots__ = ('type_class3', 'types', )
 
-    def __init__(self, type_class3: 'Type3Class') -> None:
+    type_class3: 'Type3Class'
+    types: list[TypeVariable]
+
+    def __init__(self, type_class3: 'Type3Class', types: Iterable[TypeVariable]) -> None:
         self.type_class3 = type_class3
+        self.types = list(types)
+
+        # Sanity check. AFAIK, if you have a multi-parameter type class,
+        # you can only add a constraint by supplying types for all variables
+        assert len(self.type_class3.args) == len(self.types)
+
+    def __str__(self) -> str:
+        return self.type_class3.name + ' ' + ' '.join(x.name for x in self.types)
+
+    def __repr__(self) -> str:
+        return f'Constraint_TypeClassInstanceExists({self.type_class3.name}, {self.types!r})'
 
 class TypeVariableContext:
     __slots__ = ('constraints', )
 
-    constraints: dict[TypeVariable, list[TypeVariableConstraintBase]]
+    constraints: list[ConstraintBase]
 
-    def __init__(self) -> None:
+    def __init__(self, constraints: Iterable[ConstraintBase] = ()) -> None:
-        self.constraints = {}
+        self.constraints = list(constraints)
 
     def __copy__(self) -> 'TypeVariableContext':
-        result = TypeVariableContext()
+        return TypeVariableContext(self.constraints)
-        result.constraints.update(self.constraints)
+
-        return result
+    def __str__(self) -> str:
+        if not self.constraints:
+            return ''
+
+        return '(' + ', '.join(str(x) for x in self.constraints) + ') => '
+
+    def __repr__(self) -> str:
+        return f'TypeVariableContext({self.constraints!r})'
 
 class FunctionSignature:
     __slots__ = ('context', 'args', )
@@ -65,3 +164,9 @@ class FunctionSignature:
     def __init__(self, context: TypeVariableContext, args: Iterable[Union['Type3', TypeVariable]]) -> None:
         self.context = context.__copy__()
         self.args = list(args)
+
+    def __str__(self) -> str:
+        return str(self.context) + ' -> '.join(x.name for x in self.args)
+
+    def __repr__(self) -> str:
+        return f'FunctionSignature({self.context!r}, {self.args!r})'

phasm/type3/placeholders.py

@@ -7,14 +7,13 @@ from typing import Any, Iterable, List, Optional, Protocol, Union
 
 from .types import Type3
 
-TYPE3_ASSERTION_ERROR = 'You must call phasm_type3 after calling phasm_parse before you can call any other method'
 
 class ExpressionProtocol(Protocol):
     """
     A protocol for classes that should be updated on substitution
     """
 
-    type3: 'Type3OrPlaceholder'
+    type3: Type3 | None
     """
     The type to update
     """

phasm/type3/routers.py

@@ -0,0 +1,119 @@
+from typing import Any, Callable
+
+from .functions import (
+    TypeConstructorVariable,
+    TypeVariable,
+    TypeVariableApplication_Unary,
+)
+from .typeclasses import Type3ClassArgs
+from .types import KindArgument, Type3, TypeApplication_TypeInt, TypeConstructor_Base
+
+
+class NoRouteForTypeException(Exception):
+    pass
+
+class TypeApplicationRouter[S, R]:
+    """
+    Helper class to find a method based on a constructed type
+    """
+    __slots__ = ('by_constructor', 'by_type', )
+
+    by_constructor: dict[Any, Callable[[S, Any], R]]
+    """
+    Contains all the added routing functions for constructed types
+    """
+
+    by_type: dict[Type3, Callable[[S], R]]
+    """
+    Contains all the added routing functions for constructed types
+    """
+
+    def __init__(self) -> None:
+        self.by_constructor = {}
+        self.by_type = {}
+
+    def add_n(self, typ: Type3, helper: Callable[[S], R]) -> None:
+        """
+        Lets you route to types that were not constructed
+
+        Also known types of kind *
+        """
+        self.by_type[typ] = helper
+
+    def add[T](self, constructor: TypeConstructor_Base[T], helper: Callable[[S, T], R]) -> None:
+        self.by_constructor[constructor] = helper
+
+    def __call__(self, arg0: S, typ: Type3) -> R:
+        t_helper = self.by_type.get(typ)
+        if t_helper is not None:
+            return t_helper(arg0)
+
+        c_helper = self.by_constructor.get(typ.application.constructor)
+        if c_helper is not None:
+            return c_helper(arg0, typ.application.arguments)
+
+        raise NoRouteForTypeException(arg0, typ)
+
+TypeVariableLookup = dict[TypeVariable, tuple[KindArgument, ...]]
+
+class TypeClassArgsRouter[S, R]:
+    """
+    Helper class to find a method based on a type class argument list
+    """
+    __slots__ = ('args', 'data', )
+
+    args: Type3ClassArgs
+
+    data: dict[tuple[Type3 | TypeConstructor_Base[Any], ...], Callable[[S, TypeVariableLookup], R]]
+
+    def __init__(self, args: Type3ClassArgs) -> None:
+        self.args = args
+        self.data = {}
+
+    def add(
+            self,
+            tv_map: dict[TypeVariable, Type3],
+            tc_map: dict[TypeConstructorVariable, TypeConstructor_Base[Any]],
+            helper: Callable[[S, TypeVariableLookup], R],
+        ) -> None:
+
+        key: list[Type3 | TypeConstructor_Base[Any]] = []
+
+        for tc_arg in self.args:
+            if isinstance(tc_arg, TypeVariable):
+                key.append(tv_map[tc_arg])
+            else:
+                key.append(tc_map[tc_arg])
+
+        self.data[tuple(key)] = helper
+
+    def __call__(self, arg0: S, tv_map: dict[TypeVariable, Type3]) -> R:
+        key: list[Type3 | TypeConstructor_Base[Any]] = []
+        arguments: TypeVariableLookup = {}
+
+        for tc_arg in self.args:
+            if isinstance(tc_arg, TypeVariable):
+                key.append(tv_map[tc_arg])
+                continue
+
+            for tvar, typ in tv_map.items():
+                tvar_constructor = tvar.application.constructor
+                if tvar_constructor != tc_arg:
+                    continue
+
+                key.append(typ.application.constructor)
+
+                if isinstance(tvar.application, TypeVariableApplication_Unary):
+                    # FIXME: This feels sketchy. Shouldn't the type variable
+                    # have the exact same number as arguments?
+                    if isinstance(typ.application, TypeApplication_TypeInt):
+                        arguments[tvar.application.arguments] = typ.application.arguments
+                        continue
+
+                raise NotImplementedError(tvar.application, typ.application)
+
+        t_helper = self.data.get(tuple(key))
+        if t_helper is not None:
+            return t_helper(arg0, arguments)
+
+        raise NoRouteForTypeException(arg0, tv_map)

phasm/type3/typeclasses.py

@@ -1,12 +1,14 @@
-from typing import Any, Dict, Iterable, List, Mapping, Optional, Union
+from typing import Dict, Iterable, List, Mapping, Optional, Union
 
 from .functions import (
+    Constraint_TypeClassInstanceExists,
+    ConstraintBase,
     FunctionSignature,
+    TypeConstructorVariable,
     TypeVariable,
-    TypeVariableConstraint_TypeHasTypeClass,
     TypeVariableContext,
 )
-from .types import Type3, TypeConstructor, TypeConstructor_Struct
+from .types import Type3
 
 
 class Type3ClassMethod:
@@ -19,14 +21,19 @@ class Type3ClassMethod:
         self.name = name
         self.signature = signature
 
+    def __str__(self) -> str:
+        return f'{self.name} :: {self.signature}'
+
     def __repr__(self) -> str:
         return f'Type3ClassMethod({repr(self.name)}, {repr(self.signature)})'
 
+Type3ClassArgs = tuple[TypeVariable] | tuple[TypeVariable, TypeVariable] | tuple[TypeConstructorVariable]
+
 class Type3Class:
     __slots__ = ('name', 'args', 'methods', 'operators', 'inherited_classes', )
 
     name: str
-    args: List[TypeVariable]
+    args: Type3ClassArgs
     methods: Dict[str, Type3ClassMethod]
     operators: Dict[str, Type3ClassMethod]
     inherited_classes: List['Type3Class']
@@ -34,42 +41,60 @@ class Type3Class:
     def __init__(
             self,
             name: str,
-            args: Iterable[TypeVariable],
+            args: Type3ClassArgs,
             methods: Mapping[str, Iterable[Union[Type3, TypeVariable]]],
             operators: Mapping[str, Iterable[Union[Type3, TypeVariable]]],
             inherited_classes: Optional[List['Type3Class']] = None,
+            additional_context: Optional[Mapping[str, Iterable[ConstraintBase]]] = None,
         ) -> None:
         self.name = name
-        self.args = list(args)
+        self.args = args
-
-        context = TypeVariableContext()
-        for arg in args:
-            context.constraints[arg] = [
-                TypeVariableConstraint_TypeHasTypeClass(self)
-            ]
-
-        # FIXME: Multi parameter class types
-        # To fix this, realise that an instantiation of a multi paramater type class
-        # means that the instantiation depends on the combination of type classes
-        # and so we can't store the type classes on the types anymore
-        # This also means constraints should store a tuple of types as its key
-        assert len(context.constraints) <= 1
 
         self.methods = {
-            k: Type3ClassMethod(k, FunctionSignature(context, v))
+            k: Type3ClassMethod(k, _create_signature(v, self))
             for k, v in methods.items()
         }
         self.operators = {
-            k: Type3ClassMethod(k, FunctionSignature(context, v))
+            k: Type3ClassMethod(k, _create_signature(v, self))
             for k, v in operators.items()
         }
         self.inherited_classes = inherited_classes or []
 
+        if additional_context:
+            for func_name, constraint_list in additional_context.items():
+                func = self.methods.get(func_name) or self.operators.get(func_name)
+                assert func is not None  # type hint
+
+                func.signature.context.constraints.extend(constraint_list)
+
     def __repr__(self) -> str:
         return self.name
 
-def instance_type_class(cls: Type3Class, typ: Type3 | TypeConstructor[Any] | TypeConstructor_Struct) -> None:
+def _create_signature(
-    if isinstance(typ, Type3):
+        method_arg_list: Iterable[Type3 | TypeVariable],
-        typ.classes.add(cls)
+        type_class3: Type3Class,
-    else:
+    ) -> FunctionSignature:
-        typ.type_classes.add(cls)
+    context = TypeVariableContext()
+    if not isinstance(type_class3.args[0], TypeConstructorVariable):
+        context.constraints.append(Constraint_TypeClassInstanceExists(type_class3, type_class3.args))
+
+    signature_args: list[Type3 | TypeVariable] = []
+    for method_arg in method_arg_list:
+        if isinstance(method_arg, Type3):
+            signature_args.append(method_arg)
+            continue
+
+        if isinstance(method_arg, TypeVariable):
+            type_constructor = method_arg.application.constructor
+            if type_constructor is None:
+                signature_args.append(method_arg)
+                continue
+
+            if (type_constructor, ) == type_class3.args:
+                context.constraints.append(Constraint_TypeClassInstanceExists(type_class3, [method_arg]))
+                signature_args.append(method_arg)
+                continue
+
+        raise NotImplementedError(method_arg)
+
+    return FunctionSignature(context, signature_args)

phasm/type3/types.py

@@ -2,22 +2,46 @@
 Contains the final types for use in Phasm, as well as construtors.
 """
 from typing import (
-    TYPE_CHECKING,
     Any,
-    Generic,
+    Callable,
-    Iterable,
+    Hashable,
-    Set,
+    Self,
     Tuple,
     TypeVar,
 )
 
-if TYPE_CHECKING:
+S = TypeVar('S')
-    from .typeclasses import Type3Class
+T = TypeVar('T')
-
 
 class KindArgument:
     pass
 
+class TypeApplication_Base[T: Hashable, S: Hashable]:
+    """
+    Records the constructor and arguments used to create this type.
+
+    Nullary types, or types of kind *, have both arguments set to None.
+    """
+    constructor: T
+    arguments: S
+
+    def __init__(self, constructor: T, arguments: S) -> None:
+        self.constructor = constructor
+        self.arguments = arguments
+
+    def __hash__(self) -> int:
+        return hash((self.constructor, self.arguments, ))
+
+    def __eq__(self, other: Any) -> bool:
+        if not isinstance(other, TypeApplication_Base):
+            raise NotImplementedError
+
+        return (self.constructor == other.constructor  # type: ignore[no-any-return]
+            and self.arguments == other.arguments)
+
+    def __repr__(self) -> str:
+        return f'{self.__class__.__name__}({self.constructor!r}, {self.arguments!r})'
+
 class Type3(KindArgument):
     """
     Base class for the type3 types
@@ -25,32 +49,25 @@ class Type3(KindArgument):
     (Having a separate name makes it easier to distinguish from
      Python's Type)
     """
-    __slots__ = ('name', 'classes', )
+    __slots__ = ('name', 'application', )
 
     name: str
     """
     The name of the string, as parsed and outputted by codestyle.
     """
 
-    classes: Set['Type3Class']
+    application: TypeApplication_Base[Any, Any]
     """
-    The type classes that this type implements
+    How the type was constructed; i.e. which constructor was used and which
+    type level arguments were applied to the constructor.
     """
 
-    def __init__(self, name: str, classes: Iterable['Type3Class']) -> None:
+    def __init__(self, name: str, application: TypeApplication_Base[Any, Any]) -> None:
         self.name = name
-        self.classes = set(classes)
+        self.application = application
-
-        for cls in self.classes:
-            for inh_cls in cls.inherited_classes:
-                if inh_cls not in self.classes:
-                    raise Exception(
-                        f'No instance for ({inh_cls} {self.name})'
-                        f'; required for ({cls} {self.name})'
-                    )
 
     def __repr__(self) -> str:
-        return f'Type3({repr(self.name)}, {repr(self.classes)})'
+        return f'Type3({self.name!r}, {self.application!r})'
 
     def __str__(self) -> str:
         return self.name
@@ -76,6 +93,11 @@ class Type3(KindArgument):
     def __bool__(self) -> bool:
         raise NotImplementedError
 
+class TypeApplication_Nullary(TypeApplication_Base[None, None]):
+    """
+    There was no constructor used to create this type - it's a 'simple' type like u32
+    """
+
 class IntType3(KindArgument):
     """
     Sometimes you can have an int on the type level, e.g. when using static arrays
@@ -94,6 +116,9 @@ class IntType3(KindArgument):
     def __init__(self, value: int) -> None:
         self.value = value
 
+    def __repr__(self) -> str:
+        return f'IntType3({self.value!r})'
+
     def __format__(self, format_spec: str) -> str:
         if format_spec != 's':
             raise TypeError(f'unsupported format string passed to Type3.__format__: {format_spec}')
@@ -112,27 +137,20 @@ class IntType3(KindArgument):
     def __hash__(self) -> int:
         return hash(self.value)
 
-T = TypeVar('T')
+class TypeConstructor_Base[T]:
-
-class TypeConstructor(Generic[T]):
     """
     Base class for type construtors
     """
-    __slots__ = ('name', 'classes', 'type_classes', '_cache', '_reverse_cache')
+    __slots__ = ('name', 'on_create', '_cache', )
 
     name: str
     """
     The name of the type constructor
     """
 
-    classes: Set['Type3Class']
+    on_create: Callable[[T, Type3], None]
     """
-    The type classes that this constructor implements
+    Who to let know if a type is created
-    """
-
-    type_classes: Set['Type3Class']
-    """
-    The type classes that the constructed types implement
     """
 
     _cache: dict[T, Type3]
@@ -141,32 +159,26 @@ class TypeConstructor(Generic[T]):
     it should produce the exact same result.
     """
 
-    _reverse_cache: dict[Type3, T]
+    def __init__(self, name: str, on_create: Callable[[T, Type3], None]) -> None:
-    """
-    Sometimes we need to know the key that created a type.
-    """
-
-    def __init__(self, name: str, classes: Iterable['Type3Class'], type_classes: Iterable['Type3Class']) -> None:
         self.name = name
-        self.classes = set(classes)
+        self.on_create = on_create
-        self.type_classes = set(type_classes)
 
         self._cache = {}
-        self._reverse_cache = {}
 
     def make_name(self, key: T) -> str:
         """
         Renders the type's name based on the given arguments
         """
-        raise NotImplementedError
+        raise NotImplementedError('make_name', self)
 
-    def did_construct(self, typ: Type3) -> T | None:
+    def make_application(self, key: T) -> TypeApplication_Base[Self, T]:
         """
-        Was the given type constructed by this constructor?
+        Records how the type was constructed into type.
 
-        If so, which arguments where used?
+        The type checker and compiler will need to know what
+        arguments where made to construct the type.
         """
-        return self._reverse_cache.get(typ)
+        raise NotImplementedError('make_application', self)
 
     def construct(self, key: T) -> Type3:
         """
@@ -175,21 +187,15 @@ class TypeConstructor(Generic[T]):
         """
         result = self._cache.get(key, None)
         if result is None:
-            self._cache[key] = result = Type3(self.make_name(key), self.type_classes)
+            self._cache[key] = result = Type3(self.make_name(key), self.make_application(key))
-            self._reverse_cache[result] = key
+            self.on_create(key, result)
 
         return result
 
-class TypeConstructor_Type(TypeConstructor[Type3]):
+    def __repr__(self) -> str:
-    """
+        return f'{self.__class__.__name__}({self.name!r}, ...)'
-    Base class type constructors of kind: * -> *
-    """
-    __slots__ = ()
 
-    def __call__(self, arg: Type3) -> Type3:
+class TypeConstructor_TypeInt(TypeConstructor_Base[Tuple[Type3, IntType3]]):
-        raise NotImplementedError
-
-class TypeConstructor_TypeInt(TypeConstructor[Tuple[Type3, IntType3]]):
     """
     Base class type constructors of kind: * -> Int -> *
 
@@ -197,22 +203,34 @@ class TypeConstructor_TypeInt(TypeConstructor[Tuple[Type3, IntType3]]):
     """
     __slots__ = ()
 
+    def make_application(self, key: Tuple[Type3, IntType3]) -> 'TypeApplication_TypeInt':
+        return TypeApplication_TypeInt(self, key)
+
     def make_name(self, key: Tuple[Type3, IntType3]) -> str:
         return f'{self.name} {key[0].name} {key[1].value}'
 
     def __call__(self, arg0: Type3, arg1: IntType3) -> Type3:
         return self.construct((arg0, arg1))
 
-class TypeConstructor_TypeStar(TypeConstructor[Tuple[Type3, ...]]):
+class TypeApplication_TypeInt(TypeApplication_Base[TypeConstructor_TypeInt, Tuple[Type3, IntType3]]):
+    pass
+
+class TypeConstructor_TypeStar(TypeConstructor_Base[Tuple[Type3, ...]]):
     """
     Base class type constructors of variadic kind
 
     Notably, tuple.
     """
+    def make_application(self, key: Tuple[Type3, ...]) -> 'TypeApplication_TypeStar':
+        return TypeApplication_TypeStar(self, key)
+
     def __call__(self, *args: Type3) -> Type3:
         key: Tuple[Type3, ...] = tuple(args)
         return self.construct(key)
 
+class TypeApplication_TypeStar(TypeApplication_Base[TypeConstructor_TypeStar, Tuple[Type3, ...]]):
+    pass
+
 class TypeConstructor_StaticArray(TypeConstructor_TypeInt):
     def make_name(self, key: Tuple[Type3, IntType3]) -> str:
         return f'{key[0].name}[{key[1].value}]'
@@ -221,57 +239,30 @@ class TypeConstructor_Tuple(TypeConstructor_TypeStar):
     def make_name(self, key: Tuple[Type3, ...]) -> str:
         return '(' + ', '.join(x.name for x in key) + ', )'
 
-class TypeConstructor_Struct:
+class TypeConstructor_Struct(TypeConstructor_Base[tuple[tuple[str, Type3], ...]]):
     """
-    Base class for type construtors
+    Constructs struct types
     """
-    __slots__ = ('name', 'classes', 'type_classes', '_cache', '_reverse_cache')
+    def make_application(self, key: tuple[tuple[str, Type3], ...]) -> 'TypeApplication_Struct':
+        return TypeApplication_Struct(self, key)
 
-    name: str
+    def make_name(self, key: tuple[tuple[str, Type3], ...]) -> str:
-    """
+        return f'{self.name}(' + ', '.join(
-    The name of the type constructor
+            f'{n}: {t.name}'
-    """
+            for n, t in key
+        ) + ')'
 
-    classes: Set['Type3Class']
+    def construct(self, key: T) -> Type3:
-    """
-    The type classes that this constructor implements
-    """
-
-    type_classes: Set['Type3Class']
-    """
-    The type classes that the constructed types implement
-    """
-
-    _cache: dict[str, Type3]
-    """
-    When constructing a type with the same arguments,
-    it should produce the exact same result.
-    """
-
-    _reverse_cache: dict[Type3, dict[str, Type3]]
-    """
-    After construction you may need to look up the arguments
-    used for making the type
-    """
-
-    def __init__(self, name: str, classes: Iterable['Type3Class'], type_classes: Iterable['Type3Class']) -> None:
-        self.name = name
-        self.classes = set(classes)
-        self.type_classes = set(type_classes)
-
-        self._cache = {}
-        self._reverse_cache = {}
-
-    def did_construct(self, typ: Type3) -> dict[str, Type3] | None:
         """
-        Was the given type constructed by this constructor?
+        Constructs the type by applying the given arguments to this
-
+        constructor.
-        If so, which arguments where used?
         """
-        return self._reverse_cache.get(typ)
+        raise Exception('This does not work with the caching system')
-
-    def __call__(self, name: str, args: dict[str, Type3], classes: Set['Type3Class']) -> Type3:
-        result = Type3(name, classes | self.type_classes)
-        self._reverse_cache[result] = args
 
+    def __call__(self, name: str, args: tuple[tuple[str, Type3], ...]) -> Type3:
+        result = Type3(name, self.make_application(args))
+        self.on_create(args, result)
         return result
+
+class TypeApplication_Struct(TypeApplication_Base[TypeConstructor_Struct, tuple[tuple[str, Type3], ...]]):
+    pass

phasm/wasmgenerator.py

@@ -2,7 +2,7 @@
 Helper functions to generate WASM code by writing Python functions
 """
 import functools
-from typing import Any, Callable, Dict, List, Optional, Type
+from typing import Any, Callable, Dict, Iterable, List, Optional, Type
 
 from . import wasm
 
@@ -24,6 +24,12 @@ class VarType_i32(VarType_Base):
 class VarType_i64(VarType_Base):
     wasm_type = wasm.WasmTypeInt64
 
+class VarType_f32(VarType_Base):
+    wasm_type = wasm.WasmTypeFloat32
+
+class VarType_f64(VarType_Base):
+    wasm_type = wasm.WasmTypeFloat64
+
 class Generator_i32i64:
     def __init__(self, prefix: str, generator: 'Generator') -> None:
         self.prefix = prefix
@@ -74,6 +80,9 @@ class Generator_i32(Generator_i32i64):
     def __init__(self, generator: 'Generator') -> None:
         super().__init__('i32', generator)
 
+        # 2.4.1. Numeric Instructions
+        self.wrap_i64 = functools.partial(self.generator.add_statement, 'i32.wrap_i64')
+
 class Generator_i64(Generator_i32i64):
     def __init__(self, generator: 'Generator') -> None:
         super().__init__('i64', generator)
@@ -132,10 +141,16 @@ class Generator_f32(Generator_f32f64):
     def __init__(self, generator: 'Generator') -> None:
         super().__init__('f32', generator)
 
+        # 2.4.1 Numeric Instructions
+        self.demote_f64 = functools.partial(self.generator.add_statement, 'f32.demote_f64')
+
 class Generator_f64(Generator_f32f64):
     def __init__(self, generator: 'Generator') -> None:
         super().__init__('f64', generator)
 
+        # 2.4.1 Numeric Instructions
+        self.promote_f32 = functools.partial(self.generator.add_statement, 'f64.promote_f32')
+
 class Generator_Local:
     def __init__(self, generator: 'Generator') -> None:
         self.generator = generator
@@ -155,12 +170,23 @@ class Generator_Local:
         self.generator.add_statement('local.tee', variable.name_ref, comment=comment)
 
 class GeneratorBlock:
-    def __init__(self, generator: 'Generator', name: str) -> None:
+    def __init__(self, generator: 'Generator', name: str, params: Iterable[str] = (), result: str | None = None) -> None:
         self.generator = generator
         self.name = name
+        self.params = params
+        self.result = result
 
     def __enter__(self) -> None:
-        self.generator.add_statement(self.name)
+        stmt = self.name
+        if self.params:
+            stmt = f'{stmt} ' + ' '.join(
+                f'(param {typ})'
+                for typ in self.params
+            )
+        if self.result:
+            stmt = f'{stmt} (result {self.result})'
+
+        self.generator.add_statement(stmt)
 
     def __exit__(self, exc_type: Any, exc_value: Any, traceback: Any) -> None:
         if not exc_type:
@@ -201,19 +227,18 @@ class Generator:
     def add_statement(self, name: str, *args: str, comment: Optional[str] = None) -> None:
         self.statements.append(wasm.Statement(name, *args, comment=comment))
 
-    def temp_var_i32(self, infix: str) -> VarType_i32:
+    def temp_var[T: VarType_Base](self, var: T) -> T:
         idx = 0
-        while (varname := f'__{infix}_tmp_var_{idx}__') in self.locals:
+        while (varname := f'__{var.name}_tmp_var_{idx}__') in self.locals:
             idx += 1
 
-        return VarType_i32(varname)
+        return var.__class__(varname)
+
+    def temp_var_i32(self, infix: str) -> VarType_i32:
+        return self.temp_var(VarType_i32(infix))
 
     def temp_var_u8(self, infix: str) -> VarType_u8:
-        idx = 0
+        return self.temp_var(VarType_u8(infix))
-        while (varname := f'__{infix}_tmp_var_{idx}__') in self.locals:
-            idx += 1
-
-        return VarType_u8(varname)
 
 def func_wrapper(exported: bool = True) -> Callable[[Any], wasm.Function]:
     """

tests/integration/helpers.py

@@ -4,14 +4,22 @@ from typing import Any, Generator, Iterable, List, TextIO, Union
 
 from phasm import compiler, prelude
 from phasm.codestyle import phasm_render
-from phasm.runtime import calculate_alloc_size
+from phasm.runtime import (
-from phasm.type3 import placeholders as type3placeholders
+    calculate_alloc_size,
+    calculate_alloc_size_static_array,
+    calculate_alloc_size_struct,
+    calculate_alloc_size_tuple,
+)
 from phasm.type3 import types as type3types
+from phasm.type3.routers import NoRouteForTypeException, TypeApplicationRouter
 
 from . import runners
 
 DASHES = '-' * 16
 
+class InvalidArgumentException(Exception):
+    pass
+
 class SuiteResult:
     def __init__(self) -> None:
         self.returned_value = None
@@ -65,9 +73,6 @@ class Suite:
             runner.interpreter_dump_memory(sys.stderr)
 
             for arg, arg_typ in zip(args, func_args, strict=True):
-                assert not isinstance(arg_typ, type3placeholders.PlaceholderForType), \
-                    'Cannot call polymorphic function from outside'
-
                 if arg_typ in (prelude.u8, prelude.u32, prelude.u64, ):
                     assert isinstance(arg, int)
                     wasm_args.append(arg)
@@ -83,31 +88,11 @@ class Suite:
                     wasm_args.append(arg)
                     continue
 
-                if arg_typ is prelude.bytes_:
+                try:
-                    adr = _allocate_memory_stored_value(runner, arg_typ, arg)
+                    adr = ALLOCATE_MEMORY_STORED_ROUTER((runner, arg), arg_typ)
                     wasm_args.append(adr)
-                    continue
+                except NoRouteForTypeException:
-
+                    raise NotImplementedError(arg_typ, arg)
-                assert isinstance(arg_typ, type3types.Type3)
-                sa_args = prelude.static_array.did_construct(arg_typ)
-                if sa_args is not None:
-                        adr = _allocate_memory_stored_value(runner, arg_typ, arg)
-                        wasm_args.append(adr)
-                        continue
-
-                tp_args = prelude.tuple_.did_construct(arg_typ)
-                if tp_args is not None:
-                        adr = _allocate_memory_stored_value(runner, arg_typ, arg)
-                        wasm_args.append(adr)
-                        continue
-
-                st_args = prelude.struct.did_construct(arg_typ)
-                if st_args is not None:
-                    adr = _allocate_memory_stored_value(runner, arg_typ, arg)
-                    wasm_args.append(adr)
-                    continue
-
-                raise NotImplementedError(arg_typ, arg)
 
         write_header(sys.stderr, 'Memory (pre run)')
         runner.interpreter_dump_memory(sys.stderr)
@@ -146,107 +131,89 @@ def _write_memory_stored_value(
         val_typ: type3types.Type3,
         val: Any,
     ) -> int:
-    if val_typ is prelude.bytes_:
+    try:
-        adr2 = _allocate_memory_stored_value(runner, val_typ, val)
+        adr2 = ALLOCATE_MEMORY_STORED_ROUTER((runner, val), val_typ)
         runner.interpreter_write_memory(adr, compiler.module_data_u32(adr2))
         return 4
+    except NoRouteForTypeException:
+        to_write = WRITE_LOOKUP_MAP[val_typ.name](val)
+        runner.interpreter_write_memory(adr, to_write)
+        return len(to_write)
 
-    st_args = prelude.struct.did_construct(val_typ)
+def _allocate_memory_stored_bytes(attrs: tuple[runners.RunnerBase, bytes]) -> int:
-    if st_args is not None:
+    runner, val = attrs
-        adr2 = _allocate_memory_stored_value(runner, val_typ, val)
-        runner.interpreter_write_memory(adr, compiler.module_data_u32(adr2))
-        return 4
 
-    sa_args = prelude.static_array.did_construct(val_typ)
+    assert isinstance(val, bytes)
-    if sa_args is not None:
-        adr2 = _allocate_memory_stored_value(runner, val_typ, val)
-        runner.interpreter_write_memory(adr, compiler.module_data_u32(adr2))
-        return 4
 
-    tp_args = prelude.tuple_.did_construct(val_typ)
+    adr = runner.call('stdlib.types.__alloc_bytes__', len(val))
-    if tp_args is not None:
+    assert isinstance(adr, int)
-        adr2 = _allocate_memory_stored_value(runner, val_typ, val)
-        runner.interpreter_write_memory(adr, compiler.module_data_u32(adr2))
-        return 4
 
-    to_write = WRITE_LOOKUP_MAP[val_typ.name](val)
+    sys.stderr.write(f'Allocation 0x{adr:08x} {repr(val)}\n')
-    runner.interpreter_write_memory(adr, to_write)
+    runner.interpreter_write_memory(adr + 4, val)
-    return len(to_write)
+    return adr
 
-def _allocate_memory_stored_value(
+def _allocate_memory_stored_static_array(attrs: tuple[runners.RunnerBase, Any], sa_args: tuple[type3types.Type3, type3types.IntType3]) -> int:
-        runner: runners.RunnerBase,
+    runner, val = attrs
-        val_typ: type3types.Type3,
-        val: Any
-    ) -> int:
-    if val_typ is prelude.bytes_:
-        assert isinstance(val, bytes)
 
-        adr = runner.call('stdlib.types.__alloc_bytes__', len(val))
+    sa_type, sa_len = sa_args
-        assert isinstance(adr, int)
 
-        sys.stderr.write(f'Allocation 0x{adr:08x} {repr(val)}\n')
+    if not isinstance(val, tuple):
-        runner.interpreter_write_memory(adr + 4, val)
+        raise InvalidArgumentException(f'Expected tuple of length {sa_len.value}; got {val!r} instead')
-        return adr
+    if sa_len.value != len(val):
+        raise InvalidArgumentException(f'Expected tuple of length {sa_len.value}; got {val!r} instead')
 
-    sa_args = prelude.static_array.did_construct(val_typ)
+    alloc_size = calculate_alloc_size_static_array(False, sa_args)
-    if sa_args is not None:
+    adr = runner.call('stdlib.alloc.__alloc__', alloc_size)
-            assert isinstance(val, tuple)
+    assert isinstance(adr, int)  # Type int
+    sys.stderr.write(f'Allocation 0x{adr:08x} {repr(val)}\n')
 
-            sa_type, sa_len = sa_args
+    offset = adr
+    for val_el_val in val:
+        offset += _write_memory_stored_value(runner, offset, sa_type, val_el_val)
+    return adr
 
-            alloc_size = calculate_alloc_size(val_typ)
+def _allocate_memory_stored_struct(attrs: tuple[runners.RunnerBase, Any], st_args: tuple[tuple[str, type3types.Type3], ...]) -> int:
-            adr = runner.call('stdlib.alloc.__alloc__', alloc_size)
+    runner, val = attrs
-            assert isinstance(adr, int)
-            sys.stderr.write(f'Allocation 0x{adr:08x} {repr(val)}\n')
 
-            tuple_len = sa_len.value
+    assert isinstance(val, dict)
-            assert tuple_len == len(val)
 
-            offset = adr
+    alloc_size = calculate_alloc_size_struct(False, st_args)
-            for val_el_val in val:
+    adr = runner.call('stdlib.alloc.__alloc__', alloc_size)
-                offset += _write_memory_stored_value(runner, offset, sa_type, val_el_val)
+    assert isinstance(adr, int)
-            return adr
+    sys.stderr.write(f'Allocation 0x{adr:08x} {repr(val)}\n')
 
-    val_el_typ: type3types.Type3
+    offset = adr
+    for val_el_name, val_el_typ in st_args:
+        assert val_el_name in val, f'Missing key value {val_el_name}'
+        val_el_val = val.pop(val_el_name)
+        offset += _write_memory_stored_value(runner, offset, val_el_typ, val_el_val)
 
-    tp_args = prelude.tuple_.did_construct(val_typ)
+    assert not val, f'Additional values: {list(val)!r}'
-    if tp_args is not None:
-            assert isinstance(val, tuple)
 
-            alloc_size = calculate_alloc_size(val_typ)
+    return adr
-            adr = runner.call('stdlib.alloc.__alloc__', alloc_size)
-            assert isinstance(adr, int)
-            sys.stderr.write(f'Allocation 0x{adr:08x} {repr(val)}\n')
 
-            assert len(val) == len(tp_args)
+def _allocate_memory_stored_tuple(attrs: tuple[runners.RunnerBase, Any], tp_args: tuple[type3types.Type3, ...]) -> int:
+    runner, val = attrs
 
-            offset = adr
+    assert isinstance(val, tuple)
-            for val_el_val, val_el_typ in zip(val, tp_args, strict=True):
-                assert not isinstance(val_el_typ, type3placeholders.PlaceholderForType)
 
-                offset += _write_memory_stored_value(runner, offset, val_el_typ, val_el_val)
+    alloc_size = calculate_alloc_size_tuple(False, tp_args)
-            return adr
+    adr = runner.call('stdlib.alloc.__alloc__', alloc_size)
+    assert isinstance(adr, int)
+    sys.stderr.write(f'Allocation 0x{adr:08x} {repr(val)}\n')
 
-    st_args = prelude.struct.did_construct(val_typ)
+    assert len(val) == len(tp_args)
-    if st_args is not None:
-        assert isinstance(val, dict)
 
-        alloc_size = calculate_alloc_size(val_typ)
+    offset = adr
-        adr = runner.call('stdlib.alloc.__alloc__', alloc_size)
+    for val_el_val, val_el_typ in zip(val, tp_args, strict=True):
-        assert isinstance(adr, int)
+        offset += _write_memory_stored_value(runner, offset, val_el_typ, val_el_val)
-        sys.stderr.write(f'Allocation 0x{adr:08x} {repr(val)}\n')
+    return adr
 
-        assert list(val.keys()) == list(st_args)
+ALLOCATE_MEMORY_STORED_ROUTER = TypeApplicationRouter[tuple[runners.RunnerBase, Any], Any]()
-
+ALLOCATE_MEMORY_STORED_ROUTER.add_n(prelude.bytes_, _allocate_memory_stored_bytes)
-        offset = adr
+ALLOCATE_MEMORY_STORED_ROUTER.add(prelude.static_array, _allocate_memory_stored_static_array)
-        for val_el_name, val_el_typ in st_args.items():
+ALLOCATE_MEMORY_STORED_ROUTER.add(prelude.struct, _allocate_memory_stored_struct)
-            assert not isinstance(val_el_typ, type3placeholders.PlaceholderForType)
+ALLOCATE_MEMORY_STORED_ROUTER.add(prelude.tuple_, _allocate_memory_stored_tuple)
-
-            val_el_val = val[val_el_name]
-            offset += _write_memory_stored_value(runner, offset, val_el_typ, val_el_val)
-        return adr
-
-    raise NotImplementedError(val_typ, val)
 
 def _load_memory_stored_returned_value(
         runner: runners.RunnerBase,
@@ -264,6 +231,13 @@ def _load_memory_stored_returned_value(
 
     if ret_type3 in (prelude.i8, prelude.i32, prelude.i64):
         assert isinstance(wasm_value, int), wasm_value
+
+        if ret_type3 is prelude.i8:
+            # Values are actually i32
+            # Have to reinterpret to load proper value
+            data = struct.pack('<i', wasm_value)
+            wasm_value,  = struct.unpack('<bxxx', data)
+
         return wasm_value
 
     if ret_type3 in (prelude.u8, prelude.u32, prelude.u64):
@@ -287,30 +261,9 @@ def _load_memory_stored_returned_value(
         assert isinstance(wasm_value, float), wasm_value
         return wasm_value
 
-    if ret_type3 is prelude.bytes_:
+    assert isinstance(wasm_value, int), wasm_value
-        assert isinstance(wasm_value, int), wasm_value
 
-        return _load_bytes_from_address(runner, ret_type3, wasm_value)
+    return LOAD_FROM_ADDRESS_ROUTER((runner, wasm_value), ret_type3)
-
-    assert isinstance(ret_type3, type3types.Type3) # Type hint
-
-    sa_args = prelude.static_array.did_construct(ret_type3)
-    if sa_args is not None:
-            assert isinstance(wasm_value, int), wasm_value
-
-            return _load_static_array_from_address(runner, sa_args[0], sa_args[1], wasm_value)
-
-    tp_args = prelude.tuple_.did_construct(ret_type3)
-    if tp_args is not None:
-            assert isinstance(wasm_value, int), wasm_value
-
-            return _load_tuple_from_address(runner, tp_args, wasm_value)
-
-    st_args = prelude.struct.did_construct(ret_type3)
-    if st_args is not None:
-        return _load_struct_from_address(runner, st_args, wasm_value)
-
-    raise NotImplementedError(ret_type3, wasm_value)
 
 def _unpack(runner: runners.RunnerBase, typ: type3types.Type3, inp: bytes) -> Any:
     if typ is prelude.u8:
@@ -347,41 +300,19 @@ def _unpack(runner: runners.RunnerBase, typ: type3types.Type3, inp: bytes) -> An
         assert len(inp) == 8
         return struct.unpack('<d', inp)[0]
 
-    if typ is prelude.bytes_:
+    if (prelude.InternalPassAsPointer, (typ, )) in prelude.PRELUDE_TYPE_CLASS_INSTANCES_EXISTING:
-        # Note: For bytes, inp should contain a 4 byte pointer
-        assert len(inp) == 4
-        adr = struct.unpack('<I', inp)[0]
-
-        return _load_bytes_from_address(runner, typ, adr)
-
-    if prelude.InternalPassAsPointer in typ.classes:
         # Note: For applied types, inp should contain a 4 byte pointer
         assert len(inp) == 4
         adr = struct.unpack('<I', inp)[0]
 
-        assert isinstance(typ, type3types.Type3)
+        return LOAD_FROM_ADDRESS_ROUTER((runner, adr), typ)
-
-        sa_args = prelude.static_array.did_construct(typ)
-        if sa_args is not None:
-            sa_type, sa_len = sa_args
-            return _load_static_array_from_address(runner, sa_type, sa_len, adr)
-
-        tp_args = prelude.tuple_.did_construct(typ)
-        if tp_args is not None:
-              return _load_tuple_from_address(runner, tp_args, adr)
-
-        st_args = prelude.struct.did_construct(typ)
-        if st_args is not None:
-            # Note: For structs, inp should contain a 4 byte pointer
-            assert len(inp) == 4
-            adr = struct.unpack('<I', inp)[0]
-
-            return _load_struct_from_address(runner, st_args, adr)
 
     raise NotImplementedError(typ, inp)
 
-def _load_bytes_from_address(runner: runners.RunnerBase, typ: type3types.Type3, adr: int) -> bytes:
+def _load_bytes_from_address(attrs: tuple[runners.RunnerBase, int]) -> bytes:
-    sys.stderr.write(f'Reading 0x{adr:08x} {typ:s}\n')
+    runner, adr = attrs
+
+    sys.stderr.write(f'Reading 0x{adr:08x} bytes\n')
     read_bytes = runner.interpreter_read_memory(adr, 4)
     bytes_len,  = struct.unpack('<I', read_bytes)
 
@@ -394,11 +325,11 @@ def _split_read_bytes(all_bytes: bytes, split_sizes: Iterable[int]) -> Generator
         yield all_bytes[offset:offset + size]
         offset += size
 
-def _load_static_array_from_address(runner: runners.RunnerBase, sub_typ: type3types.Type3, len_typ: type3types.IntType3, adr: int) -> Any:
+def _load_static_array_from_address(attrs: tuple[runners.RunnerBase, int], sa_args: tuple[type3types.Type3, type3types.IntType3]) -> Any:
-    sys.stderr.write(f'Reading 0x{adr:08x} {sub_typ:s} {len_typ:s}\n')
+    runner, adr = attrs
+    sub_typ, len_typ = sa_args
 
-    assert not isinstance(sub_typ, type3placeholders.PlaceholderForType)
+    sys.stderr.write(f'Reading 0x{adr:08x} {sub_typ:s} {len_typ:s}\n')
-    assert isinstance(len_typ, type3types.IntType3)
 
     sa_len = len_typ.value
 
@@ -412,37 +343,42 @@ def _load_static_array_from_address(runner: runners.RunnerBase, sub_typ: type3ty
         for arg_bytes in _split_read_bytes(read_bytes, arg_sizes)
     )
 
-def _load_tuple_from_address(runner: runners.RunnerBase, typ_args: tuple[type3types.Type3, ...], adr: int) -> Any:
+def _load_struct_from_address(attrs: tuple[runners.RunnerBase, int], st_args: tuple[tuple[str, type3types.Type3], ...]) -> dict[str, Any]:
-    sys.stderr.write(f'Reading 0x{adr:08x} tuple {len(typ_args)}\n')
+    runner, adr = attrs
 
-    arg_sizes = [
-        calculate_alloc_size(x, is_member=True)
-        for x in typ_args
-    ]
-
-    read_bytes = runner.interpreter_read_memory(adr, sum(arg_sizes))
-
-    return tuple(
-        _unpack(runner, arg_typ, arg_bytes)
-        for arg_typ, arg_bytes in zip(typ_args, _split_read_bytes(read_bytes, arg_sizes), strict=True)
-    )
-
-def _load_struct_from_address(runner: runners.RunnerBase, st_args: dict[str, type3types.Type3], adr: int) -> Any:
     sys.stderr.write(f'Reading 0x{adr:08x} struct {list(st_args)}\n')
 
-    name_list = list(st_args)
-
-    typ_list = list(st_args.values())
-    assert len(typ_list) == len(st_args)
-
     arg_sizes = [
         calculate_alloc_size(x, is_member=True)
-        for x in typ_list
+        for _, x in st_args
     ]
 
     read_bytes = runner.interpreter_read_memory(adr, sum(arg_sizes))
 
     return {
         arg_name: _unpack(runner, arg_typ, arg_bytes)
-        for arg_name, arg_typ, arg_bytes in zip(name_list, typ_list, _split_read_bytes(read_bytes, arg_sizes), strict=True)
+        for (arg_name, arg_typ, ), arg_bytes in zip(st_args, _split_read_bytes(read_bytes, arg_sizes), strict=True)
     }
+
+def _load_tuple_from_address(attrs: tuple[runners.RunnerBase, int], tp_args: tuple[type3types.Type3, ...]) -> Any:
+    runner, adr = attrs
+
+    sys.stderr.write(f'Reading 0x{adr:08x} tuple {len(tp_args)}\n')
+
+    arg_sizes = [
+        calculate_alloc_size(x, is_member=True)
+        for x in tp_args
+    ]
+
+    read_bytes = runner.interpreter_read_memory(adr, sum(arg_sizes))
+
+    return tuple(
+        _unpack(runner, arg_typ, arg_bytes)
+        for arg_typ, arg_bytes in zip(tp_args, _split_read_bytes(read_bytes, arg_sizes), strict=True)
+    )
+
+LOAD_FROM_ADDRESS_ROUTER = TypeApplicationRouter[tuple[runners.RunnerBase, int], Any]()
+LOAD_FROM_ADDRESS_ROUTER.add_n(prelude.bytes_, _load_bytes_from_address)
+LOAD_FROM_ADDRESS_ROUTER.add(prelude.static_array, _load_static_array_from_address)
+LOAD_FROM_ADDRESS_ROUTER.add(prelude.struct, _load_struct_from_address)
+LOAD_FROM_ADDRESS_ROUTER.add(prelude.tuple_, _load_tuple_from_address)

tests/integration/test_lang/test_builtins.py

@@ -49,7 +49,7 @@ def testEntry(a: bytes, b: bytes) -> u8:
 def test_foldl_3():
     code_py = """
 def xor(l: u32, r: u8) -> u32:
-    return l ^ u32(r)
+    return l ^ extend(r)
 
 @exported
 def testEntry(a: bytes) -> u32:

tests/integration/test_lang/test_bytes.py

@@ -0,0 +1,30 @@
+import pytest
+
+from ..helpers import Suite
+
+
+@pytest.mark.integration_test
+def test_bytes_export_constant():
+    code_py = """
+CONSTANT: bytes = b'Hello'
+
+@exported
+def testEntry() -> bytes:
+    return CONSTANT
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert b"Hello" == result.returned_value
+
+@pytest.mark.integration_test
+def test_bytes_export_instantiation():
+    code_py = """
+@exported
+def testEntry() -> bytes:
+    return b'Hello'
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert b"Hello" == result.returned_value

tests/integration/test_lang/test_eq.py

@@ -29,7 +29,7 @@ def testEntry(x: Foo, y: Foo) -> Foo:
     return x == y
 """
 
-    with pytest.raises(Type3Exception, match='Foo does not implement the Eq type class'):
+    with pytest.raises(Type3Exception, match='Missing type class instantation: Eq Foo'):
         Suite(code_py).run_code()
 
 @pytest.mark.integration_test
@@ -111,7 +111,7 @@ def testEntry(x: Foo, y: Foo) -> Foo:
     return x != y
 """
 
-    with pytest.raises(Type3Exception, match='Foo does not implement the Eq type class'):
+    with pytest.raises(Type3Exception, match='Missing type class instantation: Eq Foo'):
         Suite(code_py).run_code()
 
 @pytest.mark.integration_test

tests/integration/test_lang/test_extendable.py

@@ -0,0 +1,112 @@
+import pytest
+
+from phasm.type3.entry import Type3Exception
+
+from ..helpers import Suite
+
+EXTENTABLE = [
+    ('u8', 'u32', ),
+    ('u8', 'u64', ),
+    ('u32', 'u64', ),
+
+    ('i8', 'i32', ),
+    ('i8', 'i64', ),
+    ('i32', 'i64', ),
+]
+
+@pytest.mark.integration_test
+def test_extend_not_implemented():
+    code_py = """
+class Foo:
+    val: i32
+
+class Baz:
+    val: i32
+
+@exported
+def testEntry(x: Foo) -> Baz:
+    return extend(x)
+"""
+
+    with pytest.raises(Type3Exception, match='Missing type class instantation: Extendable Foo Baz'):
+        Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+@pytest.mark.parametrize('ext_from,ext_to', EXTENTABLE)
+def test_extend_ok(ext_from,ext_to):
+    code_py = f"""
+CONSTANT: {ext_from} = 10
+
+@exported
+def testEntry() -> {ext_to}:
+    return extend(CONSTANT)
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert 10 == result.returned_value
+
+@pytest.mark.integration_test
+@pytest.mark.parametrize('ext_from,in_put,ext_to,exp_out', [
+    ('u8', 241, 'u32', 241),
+    ('u32', 4059165169, 'u64', 4059165169),
+    ('u8', 241, 'u64', 241),
+
+    ('i8', 113, 'i32', 113),
+    ('i32', 1911681521, 'i64', 1911681521),
+    ('i8', 113, 'i64', 113),
+
+    ('i8', -15, 'i32', -15),
+    ('i32', -15, 'i64', -15),
+    ('i8', -15, 'i64', -15),
+
+])
+def test_extend_results(ext_from, ext_to, in_put, exp_out):
+    code_py = f"""
+@exported
+def testEntry(x: {ext_from}) -> {ext_to}:
+    return extend(x)
+"""
+
+    result = Suite(code_py).run_code(in_put)
+
+    assert exp_out == result.returned_value
+
+@pytest.mark.integration_test
+@pytest.mark.parametrize('ext_from,ext_to', EXTENTABLE)
+def test_wrap_ok(ext_from,ext_to):
+    code_py = f"""
+CONSTANT: {ext_to} = 10
+
+@exported
+def testEntry() -> {ext_from}:
+    return wrap(CONSTANT)
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert 10 == result.returned_value
+
+@pytest.mark.integration_test
+@pytest.mark.parametrize('ext_to,in_put,ext_from,exp_out', [
+    ('u32', 0xF1F1F1F1, 'u8', 0xF1),
+    ('u64', 0xF1F1F1F1F1F1F1F1, 'u32', 0xF1F1F1F1),
+    ('u64', 0xF1F1F1F1F1F1F1F1, 'u8', 0xF1),
+
+    ('i32', 0xF1F1F171, 'i8', 113),
+    ('i32', 0xF1F1F1F1, 'i8', -15),
+    ('i64', 0x71F1F1F171F1F1F1, 'i32', 1911681521),
+    ('i64', 0x71F1F1F1F1F1F1F1, 'i32', -235802127),
+    ('i64', 0xF1F1F1F1F1F1F171, 'i8', 113),
+    ('i64', 0xF1F1F1F1F1F1F1F1, 'i8', -15),
+])
+def test_wrap_results(ext_from, ext_to, in_put, exp_out):
+    code_py = f"""
+@exported
+def testEntry(x: {ext_to}) -> {ext_from}:
+    return wrap(x)
+"""
+
+    result = Suite(code_py).run_code(in_put)
+
+    assert exp_out == result.returned_value

tests/integration/test_lang/test_foldable.py

@@ -0,0 +1,71 @@
+import pytest
+
+from phasm.type3.entry import Type3Exception
+
+from ..helpers import Suite
+from .test_natnum import FLOAT_TYPES, INT_TYPES
+
+
+@pytest.mark.integration_test
+@pytest.mark.parametrize('length', [1, 5, 13])
+@pytest.mark.parametrize('a_type', INT_TYPES + FLOAT_TYPES)
+def test_foldable_sum(length, a_type):
+    code_py = f"""
+@exported
+def testEntry(x: {a_type}[{length}]) -> {a_type}:
+    return sum(x)
+"""
+
+    in_put = tuple(range(length))
+
+    result = Suite(code_py).run_code(in_put)
+
+    assert sum(in_put) == result.returned_value
+
+@pytest.mark.integration_test
+def test_foldable_sum_not_natnum():
+    code_py = """
+class Foo:
+    bar: i32
+
+@exported
+def testEntry(x: Foo[4]) -> Foo:
+    return sum(x)
+"""
+
+    with pytest.raises(Type3Exception, match='Missing type class instantation: NatNum Foo'):
+        Suite(code_py).run_code()
+
+
+@pytest.mark.integration_test
+def test_foldable_invalid_return_type():
+    code_py = """
+@exported
+def testEntry(x: i32[5]) -> f64:
+    return sum(x)
+"""
+
+    with pytest.raises(Type3Exception, match='i32 must be f64 instead'):
+        Suite(code_py).run_code((4, 5, 6, 7, 8, ))
+
+@pytest.mark.integration_test
+def test_foldable_not_constructed():
+    code_py = """
+@exported
+def testEntry(x: i32) -> i32:
+    return sum(x)
+"""
+
+    with pytest.raises(Type3Exception, match='Missing type class instantation: Foldable i32.*i32 must be a constructed type instead'):
+        Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+def test_foldable_not_foldable():
+    code_py = """
+@exported
+def testEntry(x: (i32, u32, )) -> i32:
+    return sum(x)
+"""
+
+    with pytest.raises(Type3Exception, match='Missing type class instantation: Foldable tuple'):
+        Suite(code_py).run_code()

tests/integration/test_lang/test_literals.py

@@ -6,7 +6,20 @@ from ..helpers import Suite
 
 
 @pytest.mark.integration_test
-def test_expr_constant_literal_does_not_fit():
+def test_expr_constant_literal_does_not_fit_module_constant():
+    code_py = """
+CONSTANT: u8 = 1000
+
+@exported
+def testEntry() -> u8:
+    return CONSTANT
+"""
+
+    with pytest.raises(Type3Exception, match=r'Must fit in 1 byte\(s\)'):
+        Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+def test_expr_constant_literal_does_not_fit_return():
     code_py = """
 @exported
 def testEntry() -> u8:

tests/integration/test_lang/test_natnum.py

@@ -27,7 +27,7 @@ def testEntry(x: Foo, y: Foo) -> Foo:
     return x + y
 """
 
-    with pytest.raises(Type3Exception, match='Foo does not implement the NatNum type class'):
+    with pytest.raises(Type3Exception, match='Missing type class instantation: NatNum Foo'):
         Suite(code_py).run_code()
 
 @pytest.mark.integration_test

tests/integration/test_lang/test_promotable.py

@@ -0,0 +1,51 @@
+import pytest
+
+from phasm.type3.entry import Type3Exception
+
+from ..helpers import Suite
+
+
+@pytest.mark.integration_test
+def test_promote_not_implemented():
+    code_py = """
+class Foo:
+    val: i32
+
+class Baz:
+    val: i32
+
+@exported
+def testEntry(x: Foo) -> Baz:
+    return promote(x)
+"""
+
+    with pytest.raises(Type3Exception, match='Missing type class instantation: Promotable Foo Baz'):
+        Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+def test_promote_ok():
+    code_py = """
+CONSTANT: f32 = 10.5
+
+@exported
+def testEntry() -> f64:
+    return promote(CONSTANT)
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert 10.5 == result.returned_value
+
+@pytest.mark.integration_test
+def test_demote_ok():
+    code_py = """
+CONSTANT: f64 = 10.5
+
+@exported
+def testEntry() -> f32:
+    return demote(CONSTANT)
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert 10.5 == result.returned_value

tests/integration/test_lang/test_static_array.py

@@ -30,3 +30,29 @@ def testEntry() -> i32:
 
     with pytest.raises(Type3Exception, match='Member count mismatch'):
         Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+def test_static_array_export_constant():
+    code_py = """
+CONSTANT: u8[3] = (1, 2, 3, )
+
+@exported
+def testEntry() -> u8[3]:
+    return CONSTANT
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert (1, 2, 3) == result.returned_value
+
+@pytest.mark.integration_test
+def test_static_array_export_instantiation():
+    code_py = """
+@exported
+def testEntry() -> u8[3]:
+    return (1, 2, 3, )
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert (1, 2, 3) == result.returned_value

tests/integration/test_lang/test_struct.py

@@ -64,6 +64,36 @@ def helper(shape1: Rectangle, shape2: Rectangle) -> i32:
 
     assert 545 == result.returned_value
 
+@pytest.mark.integration_test
+def test_type_mismatch_struct_call_root():
+    code_py = """
+class CheckedValueBlue:
+    value: i32
+
+class CheckedValueRed:
+    value: i32
+
+CONST: CheckedValueBlue = CheckedValueRed(1)
+"""
+
+    with pytest.raises(Type3Exception, match='CheckedValueBlue must be CheckedValueRed instead'):
+        Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+def test_type_mismatch_struct_call_nested():
+    code_py = """
+class CheckedValueBlue:
+    value: i32
+
+class CheckedValueRed:
+    value: i32
+
+CONST: (CheckedValueBlue, u32, ) = (CheckedValueRed(1), 16, )
+"""
+
+    with pytest.raises(Type3Exception, match='CheckedValueBlue must be CheckedValueRed instead'):
+        Suite(code_py).run_code()
+
 @pytest.mark.integration_test
 @pytest.mark.parametrize('type_', ['i32', 'i64', 'f32', 'f64'])
 def test_type_mismatch_struct_member(type_):
@@ -100,3 +130,47 @@ class f32:
 
     with pytest.raises(StaticError, match='f32 already defined as type'):
         Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+@pytest.mark.skip(reason='FIXME: See constraintgenerator.py for AccessStructMember')
+def test_struct_not_accessible():
+    code_py = """
+@exported
+def testEntry(x: u8) -> u8:
+    return x.y
+"""
+
+    with pytest.raises(Type3Exception, match='u8 is not struct'):
+        Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+def test_struct_export_constant():
+    code_py = """
+class CheckedValue:
+    value: i32
+
+CONSTANT: CheckedValue = CheckedValue(32)
+
+@exported
+def testEntry() -> CheckedValue:
+    return CONSTANT
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert {"value": 32} == result.returned_value
+
+@pytest.mark.integration_test
+def test_struct_export_instantiation():
+    code_py = """
+class CheckedValue:
+    value: i32
+
+@exported
+def testEntry() -> CheckedValue:
+    return CheckedValue(32)
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert {"value": 32} == result.returned_value

tests/integration/test_lang/test_subscriptable.py

@@ -23,6 +23,23 @@ def testEntry(f: {type_}) -> u8:
 
     assert exp_result == result.returned_value
 
+@pytest.mark.integration_test
+@pytest.mark.parametrize('type_, in_put, exp_result', [
+    ('(u8, u8, u8, )', (45, 46, 47), 47, ),
+    ('u8[5]', (45, 46, 47, 48, 49), 47, ),
+    ('bytes', b'This is a test', 105)
+])
+def test_subscript_2(type_, in_put, exp_result):
+    code_py = f"""
+@exported
+def testEntry(f: {type_}) -> u8:
+    return f[2]
+"""
+
+    result = Suite(code_py).run_code(in_put)
+
+    assert exp_result == result.returned_value
+
 @pytest.mark.integration_test
 @pytest.mark.parametrize('type_, in_put, exp_result', [
     ('(u8, u8, )', (45, 46), 45, ),
@@ -47,7 +64,7 @@ def testEntry(x: (u8, u32, u64), y: u8) -> u64:
     return x[y]
 """
 
-    with pytest.raises(Type3Exception, match='Must index with literal'):
+    with pytest.raises(Type3Exception, match='Must index with integer literal'):
         Suite(code_py).run_code()
 
 @pytest.mark.integration_test

tests/integration/test_lang/test_tuple.py

@@ -70,3 +70,29 @@ CONSTANT: (u32, u8, u8, ) = (24, 4000, 1, )
 
     with pytest.raises(Type3Exception, match=r'Must fit in 1 byte\(s\)'):
         Suite(code_py).run_code()
+
+@pytest.mark.integration_test
+def test_tuple_export_constant():
+    code_py = """
+CONSTANT: (u32, u8, u8, ) = (4000, 20, 20, )
+
+@exported
+def testEntry() -> (u32, u8, u8, ):
+    return CONSTANT
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert (4000, 20, 20, ) == result.returned_value
+
+@pytest.mark.integration_test
+def test_tuple_export_instantiation():
+    code_py = """
+@exported
+def testEntry() -> (u32, u8, u8, ):
+    return (4000, 20, 20, )
+"""
+
+    result = Suite(code_py).run_code()
+
+    assert (4000, 20, 20, ) == result.returned_value