Removes the cast / u32 hacky way of casting.

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

@@ -76,13 +76,6 @@ def expression(inp: ourlang.Expression) -> str:
         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):

phasm/compiler.py

@@ -484,11 +484,6 @@ def expression(wgn: WasmGenerator, inp: ourlang.Expression) -> None:
 
         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):

phasm/parser.py

@@ -489,16 +489,6 @@ class OurVisitor:
 
         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')

phasm/type3/constraints.py

@@ -197,50 +197,6 @@ class TupleMatchConstraint(ConstraintBase):
 
         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

phasm/type3/constraintsgenerator.py

@@ -12,7 +12,6 @@ from . import typeclasses as typeclasses
 from . import types as type3types
 from .constraints import (
     CanBeSubscriptedConstraint,
-    CastableConstraint,
     ConstraintBase,
     Context,
     LiteralFitsConstraint,
@@ -50,11 +49,6 @@ def expression(ctx: Context, inp: ourlang.Expression) -> ConstraintGenerator:
         return
 
     if isinstance(inp, ourlang.UnaryOp):
-        if 'cast' == inp.operator:
-            yield from expression(ctx, inp.right)
-            yield CastableConstraint(inp.right.type3, inp.type3)
-            return
-
         raise NotImplementedError(expression, inp, inp.operator)
 
     if isinstance(inp, ourlang.BinaryOp) or isinstance(inp, ourlang.FunctionCall):

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: