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And Specification

and_specification

AndSpecification

Bases: ComposableSpecification[T]

Logical AND of two specifications.

Satisfied if and only if both left and right specifications are satisfied.

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

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_active = ExpressionSpecification(lambda u: u.is_active, "is_active")
is_admin = ExpressionSpecification(lambda u: u.role == "admin", "is_admin")

# Direct construction
active_admin = AndSpecification(is_active, is_admin)
# Equivalent via operator
same = is_active & is_admin  # Produces an AndSpecification
Source code in src/forging_blocks/domain/specification/logical_operators/and_specification.py 
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class AndSpecification[T](ComposableSpecification[T]):
    """Logical AND of two specifications.

    Satisfied if and only if both left and right specifications are satisfied.

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

    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_active = ExpressionSpecification(lambda u: u.is_active, "is_active")
        is_admin = ExpressionSpecification(lambda u: u.role == "admin", "is_admin")

        # Direct construction
        active_admin = AndSpecification(is_active, is_admin)
        # Equivalent via operator
        same = is_active & is_admin  # Produces an AndSpecification
        ```
    """

    __slots__ = ("_left_specification", "_right_specification")

    def __init__(self, left: Specification[T], right: Specification[T]) -> None:
        self._left_specification = left
        self._right_specification = right

    def is_satisfied_by(self, candidate: T) -> bool:
        return self._left_specification.is_satisfied_by(
            candidate
        ) and self._right_specification.is_satisfied_by(candidate)

    def __repr__(self) -> str:
        return f"AndSpecification({self._left_specification!r}, {self._right_specification!r})"