type_api.py 文件源码

def coerce_compared_value(self, op, value):
        """Suggest a type for a 'coerced' Python value in an expression.

        Default behavior for :class:`.UserDefinedType` is the
        same as that of :class:`.TypeDecorator`; by default it returns
        ``self``, assuming the compared value should be coerced into
        the same type as this one.  See
        :meth:`.TypeDecorator.coerce_compared_value` for more detail.

        .. versionchanged:: 0.8 :meth:`.UserDefinedType.coerce_compared_value`
           now returns ``self`` by default, rather than falling onto the
           more fundamental behavior of
           :meth:`.TypeEngine.coerce_compared_value`.

        """

        return self