38e43944c7
type5 is much more first principles based, so we get a lot of weird quirks removed: - FromLiteral no longer needs to understand AST - Type unifications works more like Haskell - Function types are just ordinary types, saving a lot of manual busywork and more.
44 lines
1.1 KiB
Python
44 lines
1.1 KiB
Python
from .record import Record
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from .typeexpr import (
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AtomicType,
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TypeApplication,
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TypeConstructor,
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TypeExpr,
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TypeVariable,
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)
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class TypeRouter[T]:
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def when_atomic(self, typ: AtomicType) -> T:
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raise NotImplementedError(typ)
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def when_application(self, typ: TypeApplication) -> T:
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raise NotImplementedError(typ)
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def when_constructor(self, typ: TypeConstructor) -> T:
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raise NotImplementedError(typ)
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def when_record(self, typ: Record) -> T:
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raise NotImplementedError(typ)
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def when_variable(self, typ: TypeVariable) -> T:
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raise NotImplementedError(typ)
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def __call__(self, typ: TypeExpr) -> T:
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if isinstance(typ, AtomicType):
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if isinstance(typ, Record):
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return self.when_record(typ)
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return self.when_atomic(typ)
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if isinstance(typ, TypeApplication):
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return self.when_application(typ)
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if isinstance(typ, TypeConstructor):
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return self.when_constructor(typ)
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if isinstance(typ, TypeVariable):
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return self.when_variable(typ)
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raise NotImplementedError(typ)
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