Class TypeVarType

mypy/types.py:641–755

Type that refers to a type variable.

class TypeVarType(TypeVarLikeType):
    """Type that refers to a type variable."""

    __slots__ = ("values", "variance")

    values: list[Type]  # Value restriction, empty list if no restriction
    variance: int

    def __init__(
        self,
        name: str,
        fullname: str,
        id: TypeVarId,
        values: list[Type],
        upper_bound: Type,
        default: Type,
        variance: int = INVARIANT,
        line: int = -1,
        column: int = -1,
    ) -> None:
        super().__init__(name, fullname, id, upper_bound, default, line, column)
        assert values is not None, "No restrictions must be represented by empty list"
        self.values = values
        self.variance = variance

    def copy_modified(
        self,
        *,
        values: Bogus[list[Type]] = _dummy,
        upper_bound: Bogus[Type] = _dummy,
        default: Bogus[Type] = _dummy,
        id: Bogus[TypeVarId] = _dummy,
        line: int = _dummy_int,
        column: int = _dummy_int,
        **kwargs: Any,
    ) -> TypeVarType:
        return TypeVarType(
            name=self.name,
            fullname=self.fullname,
            id=self.id if id is _dummy else id,
            values=self.values if values is _dummy else values,
            upper_bound=self.upper_bound if upper_bound is _dummy else upper_bound,
            default=self.default if default is _dummy else default,
            variance=self.variance,
            line=self.line if line == _dummy_int else line,
            column=self.column if column == _dummy_int else column,
        )

    def accept(self, visitor: TypeVisitor[T]) -> T:
        return visitor.visit_type_var(self)

    def __hash__(self) -> int:
        return hash((self.id, self.upper_bound, tuple(self.values)))

    def __eq__(self, other: object) -> bool:
        if not isinstance(other, TypeVarType):
            return NotImplemented
        return (