core.py 文件源码

def extract_arg(self, name):
        """
        returns an argument as a variable, given its name

        name: str
            variable name
        """
        if name is None:
            return None

        var = None
        if isinstance(name, (Integer, Float)):
            var = Integer(name)
        elif isinstance(name, str):
            if name in namespace:
                var = namespace[name]
            else:
                raise Exception("could not find {} in namespace ".format(name))
        elif isinstance(name, ArithmeticExpression):
            var = do_arg(name)
        else:
            raise Exception("Unexpected type {0} for {1}".format(type(name), name))

        return var