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Not Callable Predicate Error

not_callable_predicate_error

NotCallablePredicateError module.

Defines the NotCallablePredicateError exception that is raised when a specification
predicate is not callable. This error is typically raised by ExpressionSpecification
when an invalid predicate is provided during initialization.

NotCallablePredicateError

Bases: Error[MetadataType]

Exception raised when a specification predicate is not callable.

This error is raised by ExpressionSpecification when the provided predicate
argument is not a callable object. The error message includes the actual type
of the predicate that was provided, helping developers identify and fix the issue.

Attributes:

Name Type Description
message ErrorMessage

Structured error message containing the type name of the invalid predicate.
metadata ErrorMetadata[MetadataType]

Optional metadata providing additional context about the error.
context MetadataType

Shortcut access to the metadata context dictionary.
Example

from forging_blocks.foundation.specification import ExpressionSpecification
spec = ExpressionSpecification(123) # Not callable
Traceback (most recent call last):
...
NotCallablePredicateError: predicate must be Callable and not int

Source code in src/forging_blocks/foundation/errors/not_callable_predicate_error.py 
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class NotCallablePredicateError[MetadataType: Mapping[str, object]](Error[MetadataType]):
    """Exception raised when a specification predicate is not callable.

    This error is raised by ExpressionSpecification when the provided predicate
    argument is not a callable object. The error message includes the actual type
    of the predicate that was provided, helping developers identify and fix the issue.

    Attributes:
        message: Structured error message containing the type name of the invalid predicate.
        metadata: Optional metadata providing additional context about the error.
        context: Shortcut access to the metadata context dictionary.

    Example:
        >>> from forging_blocks.foundation.specification import ExpressionSpecification
        >>> spec = ExpressionSpecification(123)  # Not callable
        Traceback (most recent call last):
            ...
        NotCallablePredicateError: predicate must be Callable and not int
    """

    def __init__(
        self,
        predicate: object,
    ) -> None:
        """Initialize the NotCallablePredicateError with the invalid predicate.

        Args:
            predicate: The object that was provided as a predicate but is not callable.
                The type name of this object will be included in the error message.
        """
        message = ErrorMessage(f"predicate must be Callable and not {type(predicate).__name__}")
        super().__init__(message)

__init__(predicate: object) -> None

Initialize the NotCallablePredicateError with the invalid predicate.

Parameters:

Name Type Description Default
predicate object

The object that was provided as a predicate but is not callable.
The type name of this object will be included in the error message.

 required
Source code in src/forging_blocks/foundation/errors/not_callable_predicate_error.py 
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def __init__(
    self,
    predicate: object,
) -> None:
    """Initialize the NotCallablePredicateError with the invalid predicate.

    Args:
        predicate: The object that was provided as a predicate but is not callable.
            The type name of this object will be included in the error message.
    """
    message = ErrorMessage(f"predicate must be Callable and not {type(predicate).__name__}")
    super().__init__(message)