basic.py 文件源码

def _recursive_call(expr_to_call, on_args):
        def the_call_method_is_overridden(expr):
            for cls in getmro(type(expr)):
                if '__call__' in cls.__dict__:
                    return cls != Basic

        if callable(expr_to_call) and the_call_method_is_overridden(expr_to_call):
            if isinstance(expr_to_call, C.Symbol):  # XXX When you call a Symbol it is
                return expr_to_call               # transformed into an UndefFunction
            else:
                return expr_to_call(*on_args)
        elif expr_to_call.args:
            args = [Basic._recursive_call(
                sub, on_args) for sub in expr_to_call.args]
            return type(expr_to_call)(*args)
        else:
            return expr_to_call