deprecated() — langchain Function Reference

Source Code

libs/core/langchain_core/_api/deprecation.py lines 89–426

def deprecated(
    since: str,
    *,
    message: str = "",
    name: str = "",
    alternative: str = "",
    alternative_import: str = "",
    pending: bool = False,
    obj_type: str = "",
    addendum: str = "",
    removal: str = "",
    package: str = "",
) -> Callable[[T], T]:
    """Decorator to mark a function, a class, or a property as deprecated.

    When deprecating a classmethod, a staticmethod, or a property, the `@deprecated`
    decorator should go *under* `@classmethod` and `@staticmethod` (i.e., `deprecated`
    should directly decorate the underlying callable), but *over* `@property`.

    When deprecating a class `C` intended to be used as a base class in a multiple
    inheritance hierarchy, `C` *must* define an `__init__` method (if `C` instead
    inherited its `__init__` from its own base class, then `@deprecated` would mess up
    `__init__` inheritance when installing its own (deprecation-emitting) `C.__init__`).

    Parameters are the same as for `warn_deprecated`, except that *obj_type* defaults to
    'class' if decorating a class, 'attribute' if decorating a property, and 'function'
    otherwise.

    Args:
        since: The release at which this API became deprecated.
        message: Override the default deprecation message.

            The `%(since)s`, `%(name)s`, `%(alternative)s`, `%(obj_type)s`,
            `%(addendum)s`, and `%(removal)s` format specifiers will be replaced by the
            values of the respective arguments passed to this function.
        name: The name of the deprecated object.
        alternative: An alternative API that the user may use in place of the deprecated
            API.

            The deprecation warning will tell the user about this alternative if
            provided.
        alternative_import: An alternative import that the user may use instead.
        pending: If `True`, uses a `PendingDeprecationWarning` instead of a
            `DeprecationWarning`.

            Cannot be used together with removal.
        obj_type: The object type being deprecated.
        addendum: Additional text appended directly to the final message.
        removal: The expected removal version.

            With the default (an empty string), a removal version is automatically
            computed from since. Set to other Falsy values to not schedule a removal
            date.

            Cannot be used together with pending.
        package: The package of the deprecated object.

    Returns:
        A decorator to mark a function or class as deprecated.

    Example:
        ```python
        @deprecated("1.4.0")
        def the_function_to_deprecate():
            pass
        ```
    """
    _validate_deprecation_params(
        removal, alternative, alternative_import, pending=pending
    )

    def deprecate(
        obj: T,
        *,
        _obj_type: str = obj_type,
        _name: str = name,
        _message: str = message,
        _alternative: str = alternative,
        _alternative_import: str = alternative_import,
        _pending: bool = pending,
        _addendum: str = addendum,