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Not Specification

not_specification

NotSpecification

Bases: ComposableSpecification[T]

Logical NOT of a specification.

Satisfied if and only if the wrapped specification is NOT satisfied.

Inherits composition operators from ComposableSpecification so that the
result of a negation is itself composable (e.g. (~a) & b).

Example 
class ExpressionSpecification(ComposableSpecification[object]):
    # Inline stub for the example.
    def __init__(self, func, description: str) -> None:
        self._func = func
        self.description = description

    def is_satisfied_by(self, candidate: object) -> bool:
        return self._func(candidate)


is_banned = ExpressionSpecification(lambda u: u.status == "banned", "is_banned")

# Direct construction
not_banned = NotSpecification(is_banned)
# Equivalent via operator
same = ~is_banned  # Produces a NotSpecification
Source code in src/forging_blocks/domain/specification/logical_operators/not_specification.py 
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class NotSpecification[T](ComposableSpecification[T]):
    """Logical NOT of a specification.

    Satisfied if and only if the wrapped specification is NOT satisfied.

    Inherits composition operators from ``ComposableSpecification`` so that the
    result of a negation is itself composable (e.g. ``(~a) & b``).

    Example:
        ```python
        class ExpressionSpecification(ComposableSpecification[object]):
            # Inline stub for the example.
            def __init__(self, func, description: str) -> None:
                self._func = func
                self.description = description

            def is_satisfied_by(self, candidate: object) -> bool:
                return self._func(candidate)


        is_banned = ExpressionSpecification(lambda u: u.status == "banned", "is_banned")

        # Direct construction
        not_banned = NotSpecification(is_banned)
        # Equivalent via operator
        same = ~is_banned  # Produces a NotSpecification
        ```
    """

    __slots__ = ("_wrapped_specification",)

    def __init__(self, wrapped: Specification[T]) -> None:
        self._wrapped_specification = wrapped

    def is_satisfied_by(self, candidate: T) -> bool:
        return not self._wrapped_specification.is_satisfied_by(candidate)

    def __repr__(self) -> str:
        return f"NotSpecification({self._wrapped_specification!r})"