Idea: constraints should only have placeholders

They were exposed on AST, causing confusion.
Now they're only used in constraints.

TODO.md

@@ -28,3 +28,8 @@
   - Functions don't seem to be a thing on typing level yet?
   - Related to the FIXME in phasm_type3?
   - Type constuctor should also be able to constuct placeholders - somehow.
+
+
+- Check placeholders only used in constraints and constraintgenerator
+- Simply typed check in compiler:
+  - isinstance(element.type3, type3types.Type3) => element.type3 is not None

phasm/codestyle.py

@@ -6,6 +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
 
 
@@ -17,10 +18,12 @@ def phasm_render(inp: ourlang.Module) -> str:
 
 Statements = Generator[str, None, None]
 
-def type3(inp: Type3) -> str:
+def type3(inp: Type3OrPlaceholder) -> str:
     """
     Render: type's name
     """
+    assert isinstance(inp, Type3), TYPE3_ASSERTION_ERROR
+
     if inp is prelude.none:
         return 'None'
 

phasm/compiler.py

@@ -9,12 +9,11 @@ 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 import placeholders as type3placeholders
 from .type3 import typeclasses as type3classes
 from .type3 import types as type3types
 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
@@ -269,14 +268,14 @@ def phasm_compile(inp: ourlang.Module) -> wasm.Module:
     """
     return module(inp)
 
-def type3(inp: type3types.Type3) -> wasm.WasmType:
+def type3(inp: type3placeholders.Type3OrPlaceholder) -> wasm.WasmType:
     """
     Compile: type
 
     Types are used for example in WebAssembly function parameters
     and return types.
     """
-    assert inp is not None, TYPE3_ASSERTION_ERROR
+    assert isinstance(inp, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
 
     if inp == prelude.none:
         return wasm.WasmTypeNone()
@@ -328,7 +327,7 @@ def tuple_instantiation(wgn: WasmGenerator, inp: ourlang.TupleInstantiation) ->
     """
     Compile: Instantiation (allocation) of a tuple
     """
-    assert inp.type3 is not None, TYPE3_ASSERTION_ERROR
+    assert isinstance(inp.type3, type3types.Type3)
 
     args: list[type3types.Type3] = []
 
@@ -346,7 +345,7 @@ def tuple_instantiation(wgn: WasmGenerator, inp: ourlang.TupleInstantiation) ->
 
     comment_elements = ''
     for element in inp.elements:
-        assert element.type3 is not None, TYPE3_ASSERTION_ERROR
+        assert isinstance(element.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
         comment_elements += f'{element.type3.name}, '
 
     tmp_var = wgn.temp_var_i32('tuple_adr')
@@ -360,11 +359,17 @@ 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, (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')
@@ -387,7 +392,7 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
         raise Exception
 
     if isinstance(inp, ourlang.ConstantPrimitive):
-        assert inp.type3 is not None, TYPE3_ASSERTION_ERROR
+        assert isinstance(inp.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
 
         if inp.type3 in (prelude.i8, prelude.u8, ):
             # No native u8 type - treat as i32, with caution
@@ -428,7 +433,7 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
             return
 
         if isinstance(inp.variable, ourlang.ModuleConstantDef):
-            assert inp.type3 is not None, TYPE3_ASSERTION_ERROR
+            assert isinstance(inp.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
 
             if (prelude.InternalPassAsPointer, (inp.type3, )) in prelude.PRELUDE_TYPE_CLASS_INSTANCES_EXISTING:
                 assert isinstance(inp.variable.constant, (ourlang.ConstantBytes, ourlang.ConstantStruct, ourlang.ConstantTuple, ))
@@ -438,8 +443,11 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
                 wgn.i32.const(address)
                 return
 
-            expression(wgn, inp.variable.constant)
-            return
+            if isinstance(inp.type3, type3types.Type3):
+                expression(wgn, inp.variable.constant)
+                return
+
+            raise NotImplementedError(expression, inp)
 
         raise NotImplementedError(expression, inp.variable)
 
@@ -447,7 +455,7 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
         expression(wgn, inp.left)
         expression(wgn, inp.right)
 
-        assert inp.type3 is not None, TYPE3_ASSERTION_ERROR
+        assert isinstance(inp.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
 
         type_var_map: Dict[type3functions.TypeVariable, type3types.Type3] = {}
 
@@ -456,7 +464,7 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
                 # Fixed type, not part of the lookup requirements
                 continue
 
-            assert arg_expr.type3 is not None, TYPE3_ASSERTION_ERROR
+            assert isinstance(arg_expr.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
             type_var_map[type_var] = arg_expr.type3
 
         instance_key = ','.join(
@@ -484,7 +492,7 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
                     # Fixed type, not part of the lookup requirements
                     continue
 
-                assert arg_expr.type3 is not None, TYPE3_ASSERTION_ERROR
+                assert isinstance(arg_expr.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
                 type_var_map[type_var] = arg_expr.type3
 
             instance_key = ','.join(
@@ -507,7 +515,7 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
         return
 
     if isinstance(inp, ourlang.Subscript):
-        assert inp.varref.type3 is not None, TYPE3_ASSERTION_ERROR
+        assert isinstance(inp.varref.type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
 
         if inp.varref.type3 is prelude.bytes_:
             expression(wgn, inp.varref)
@@ -515,7 +523,7 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
             wgn.call(stdlib_types.__subscript_bytes__)
             return
 
-        assert inp.varref.type3 is not None, TYPE3_ASSERTION_ERROR
+        assert isinstance(inp.varref.type3, type3types.Type3)
 
         sa_args = prelude.static_array.did_construct(inp.varref.type3)
         if sa_args is not None:
@@ -541,6 +549,7 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
                 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')
@@ -553,17 +562,18 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
 
                 offset = 0
                 for el_type in tp_args[0:inp.index.value]:
-                    assert el_type is not None, TYPE3_ASSERTION_ERROR
+                    assert isinstance(el_type, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
                     offset += calculate_alloc_size(el_type)
 
                 el_type = tp_args[inp.index.value]
-                assert el_type is not None, TYPE3_ASSERTION_ERROR
+                assert isinstance(el_type, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
 
                 expression(wgn, inp.varref)
 
                 if (prelude.InternalPassAsPointer, (el_type, )) in prelude.PRELUDE_TYPE_CLASS_INSTANCES_EXISTING:
                     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}')
@@ -572,13 +582,14 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
         raise NotImplementedError(expression, inp, inp.varref.type3)
 
     if isinstance(inp, ourlang.AccessStructMember):
-        assert inp.struct_type3 is not None, TYPE3_ASSERTION_ERROR
+        assert isinstance(inp.struct_type3, type3types.Type3), type3placeholders.TYPE3_ASSERTION_ERROR
 
         st_args = prelude.struct.did_construct(inp.struct_type3)
         assert st_args is not None
 
         member_type = st_args[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)
@@ -597,7 +608,7 @@ def expression_fold(wgn: WasmGenerator, inp: ourlang.Fold) -> None:
     """
     Compile: Fold expression
     """
-    assert inp.type3 is not None, TYPE3_ASSERTION_ERROR
+    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)
@@ -828,7 +839,7 @@ def module_data(inp: ourlang.ModuleData) -> bytes:
         data_list: List[bytes] = []
 
         for constant in block.data:
-            assert constant.type3 is not None, TYPE3_ASSERTION_ERROR
+            assert isinstance(constant.type3, type3types.Type3), (id(constant), type3placeholders.TYPE3_ASSERTION_ERROR)
 
             if isinstance(constant, ourlang.ConstantMemoryStored) and block is not constant.data_block:
                 # It's stored in a different block

phasm/parser.py

@@ -163,8 +163,8 @@ class OurVisitor:
 
             arg_type = self.visit_type(module, arg.annotation)
 
-            # FIXME: Allow TypeVariable in the function signature
-            # This would also require FunctionParam to accept a placeholder
+            # if isisntance(arg_type, TypeVariable):
+            #   arg_type = PlaceHolderForType()
 
             function.signature.args.append(arg_type)
             function.posonlyargs.append(FunctionParam(

phasm/type3/constraints.py

@@ -33,13 +33,13 @@ class RequireTypeSubstitutes:
     typing of the program, so this constraint can be updated.
     """
 
-SubstitutionMap = Dict[placeholders.PlaceholderForType, types.Type3]
+SubstitutionMap = Dict[PlaceholderForType, types.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[str, ourlang.Expression, types.Type3, PlaceholderForType]]]
 
 class Context:
     """
@@ -99,9 +99,9 @@ class SameTypeConstraint(ConstraintBase):
     """
     __slots__ = ('type_list', )
 
-    type_list: List[placeholders.Type3OrPlaceholder]
+    type_list: List[PlaceholderForType]
 
-    def __init__(self, *type_list: placeholders.Type3OrPlaceholder, comment: Optional[str] = None) -> None:
+    def __init__(self, *type_list: PlaceholderForType, comment: Optional[str] = None) -> None:
         super().__init__(comment=comment)
 
         assert len(type_list) > 1
@@ -111,18 +111,10 @@ class SameTypeConstraint(ConstraintBase):
         known_types: List[types.Type3] = []
         phft_list = []
         for typ in self.type_list:
-            if isinstance(typ, types.Type3):
-                known_types.append(typ)
-                continue
-
-            if isinstance(typ, placeholders.PlaceholderForType):
-                if typ.resolve_as is not None:
-                    known_types.append(typ.resolve_as)
-                else:
-                    phft_list.append(typ)
-                continue
-
-            raise NotImplementedError(typ)
+            if typ.resolve_as is not None:
+                known_types.append(typ.resolve_as)
+            else:
+                phft_list.append(typ)
 
         if not known_types:
             return RequireTypeSubstitutes()
@@ -158,7 +150,7 @@ class SameTypeConstraint(ConstraintBase):
         return f'SameTypeConstraint({args}, comment={repr(self.comment)})'
 
 class TupleMatchConstraint(ConstraintBase):
-    def __init__(self, exp_type: placeholders.Type3OrPlaceholder, args: Iterable[placeholders.Type3OrPlaceholder], comment: str):
+    def __init__(self, exp_type: PlaceholderForType, args: Iterable[PlaceholderForType], comment: str):
         super().__init__(comment=comment)
 
         self.exp_type = exp_type
@@ -166,7 +158,7 @@ class TupleMatchConstraint(ConstraintBase):
 
     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()
 
@@ -206,13 +198,13 @@ class MustImplementTypeClassConstraint(ConstraintBase):
 
     context: Context
     type_class3: Union[str, typeclasses.Type3Class]
-    types: list[placeholders.Type3OrPlaceholder]
+    types: list[PlaceholderForType]
 
     DATA = {
         'bytes': {'Foldable'},
     }
 
-    def __init__(self, context: Context, type_class3: Union[str, typeclasses.Type3Class], types: list[placeholders.Type3OrPlaceholder], comment: Optional[str] = None) -> None:
+    def __init__(self, context: Context, type_class3: Union[str, typeclasses.Type3Class], types: list[PlaceholderForType], comment: Optional[str] = None) -> None:
         super().__init__(comment=comment)
 
         self.context = context
@@ -222,10 +214,10 @@ class MustImplementTypeClassConstraint(ConstraintBase):
     def check(self) -> CheckResult:
         typ_list = []
         for typ in self.types:
-            if isinstance(typ, placeholders.PlaceholderForType) and typ.resolve_as is not None:
+            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()
 
             typ_list.append(typ)
@@ -267,12 +259,12 @@ class LiteralFitsConstraint(ConstraintBase):
     """
     __slots__ = ('type3', 'literal', )
 
-    type3: placeholders.Type3OrPlaceholder
+    type3: PlaceholderForType
     literal: Union[ourlang.ConstantPrimitive, ourlang.ConstantBytes, ourlang.ConstantTuple, ourlang.ConstantStruct]
 
     def __init__(
             self,
-            type3: placeholders.Type3OrPlaceholder,
+            type3: PlaceholderForType,
             literal: Union[ourlang.ConstantPrimitive, ourlang.ConstantBytes, ourlang.ConstantTuple, ourlang.ConstantStruct],
             comment: Optional[str] = None,
         ) -> None:
@@ -296,7 +288,7 @@ 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()
 
@@ -436,17 +428,17 @@ class CanBeSubscriptedConstraint(ConstraintBase):
     """
     __slots__ = ('ret_type3', 'type3', 'index', 'index_phft', )
 
-    ret_type3: placeholders.Type3OrPlaceholder
-    type3: placeholders.Type3OrPlaceholder
+    ret_type3: PlaceholderForType
+    type3: PlaceholderForType
     index: ourlang.Expression
-    index_phft: placeholders.Type3OrPlaceholder
+    index_phft: PlaceholderForType
 
     def __init__(
             self,
-            ret_type3: placeholders.PlaceholderForType,
-            type3: placeholders.PlaceholderForType,
+            ret_type3: PlaceholderForType,
+            type3: PlaceholderForType,
             index: ourlang.Expression,
-            index_phft: placeholders.PlaceholderForType,
+            index_phft: PlaceholderForType,
             comment: Optional[str] = None,
         ) -> None:
         super().__init__(comment=comment)
@@ -458,7 +450,7 @@ class CanBeSubscriptedConstraint(ConstraintBase):
 
     def check(self) -> CheckResult:
         exp_type = self.type3
-        if isinstance(exp_type, placeholders.PlaceholderForType):
+        if isinstance(exp_type, PlaceholderForType):
             if exp_type.resolve_as is None:
                 return RequireTypeSubstitutes()
 

phasm/type3/placeholders.py

@@ -7,6 +7,7 @@ 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):
     """

tests/integration/helpers.py

@@ -5,6 +5,7 @@ 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.type3 import placeholders as type3placeholders
 from phasm.type3 import types as type3types
 
 from . import runners
@@ -64,6 +65,9 @@ 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)
@@ -84,6 +88,7 @@ class Suite:
                     wasm_args.append(adr)
                     continue
 
+                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)
@@ -217,6 +222,8 @@ def _allocate_memory_stored_value(
 
             offset = adr
             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)
             return adr
 
@@ -233,6 +240,8 @@ def _allocate_memory_stored_value(
 
         offset = adr
         for val_el_name, val_el_typ in st_args.items():
+            assert not isinstance(val_el_typ, type3placeholders.PlaceholderForType)
+
             val_el_val = val[val_el_name]
             offset += _write_memory_stored_value(runner, offset, val_el_typ, val_el_val)
         return adr
@@ -290,6 +299,8 @@ def _load_memory_stored_returned_value(
 
         return _load_bytes_from_address(runner, ret_type3, wasm_value)
 
+    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
@@ -355,6 +366,8 @@ def _unpack(runner: runners.RunnerBase, typ: type3types.Type3, inp: bytes) -> An
         assert len(inp) == 4
         adr = struct.unpack('<I', inp)[0]
 
+        assert isinstance(typ, type3types.Type3)
+
         sa_args = prelude.static_array.did_construct(typ)
         if sa_args is not None:
             sa_type, sa_len = sa_args
@@ -391,6 +404,9 @@ def _split_read_bytes(all_bytes: bytes, split_sizes: Iterable[int]) -> Generator
 def _load_static_array_from_address(runner: runners.RunnerBase, sub_typ: type3types.Type3, len_typ: type3types.IntType3, adr: int) -> Any:
     sys.stderr.write(f'Reading 0x{adr:08x} {sub_typ:s} {len_typ:s}\n')
 
+    assert not isinstance(sub_typ, type3placeholders.PlaceholderForType)
+    assert isinstance(len_typ, type3types.IntType3)
+
     sa_len = len_typ.value
 
     arg_size_1 = calculate_alloc_size(sub_typ, is_member=True)