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Validate Call

Decorator for validating function calls.

validate_call 

validate_call(
    func: AnyCallableT | None = None,
    /,
    *,
    config: ConfigDict | None = None,
    validate_return: bool = False,
) -> AnyCallableT | Callable[[AnyCallableT], AnyCallableT]

Usage Documentation

Validation Decorator

Returns a decorated wrapper around the function that validates the arguments and, optionally, the return value.

Usage may be either as a plain decorator @validate_call or with arguments @validate_call(...).

Parameters:

Name Type Description Default
func AnyCallableT | None

The function to be decorated.

 None
config ConfigDict | None

The configuration dictionary.

 None
validate_return bool

Whether to validate the return value.

 False

Returns:

Type Description
AnyCallableT | Callable[[AnyCallableT], AnyCallableT]

The decorated function.
Source code in pydantic/validate_call_decorator.py 
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def validate_call(
    func: AnyCallableT | None = None,
    /,
    *,
    config: ConfigDict | None = None,
    validate_return: bool = False,
) -> AnyCallableT | Callable[[AnyCallableT], AnyCallableT]:
    """Usage docs: https://docs.pydantic.dev/2.10/concepts/validation_decorator/

    Returns a decorated wrapper around the function that validates the arguments and, optionally, the return value.

    Usage may be either as a plain decorator `@validate_call` or with arguments `@validate_call(...)`.

    Args:
        func: The function to be decorated.
        config: The configuration dictionary.
        validate_return: Whether to validate the return value.

    Returns:
        The decorated function.
    """
    parent_namespace = _typing_extra.parent_frame_namespace()

    def validate(function: AnyCallableT) -> AnyCallableT:
        _check_function_type(function)
        validate_call_wrapper = _validate_call.ValidateCallWrapper(
            cast(_validate_call.ValidateCallSupportedTypes, function), config, validate_return, parent_namespace
        )
        return _validate_call.update_wrapper_attributes(function, validate_call_wrapper.__call__)  # type: ignore

    if func is not None:
        return validate(func)
    else:
        return validate