parser.py 文件源码

def parse_subscribed(self):
        lineno = self.stream.current.lineno

        if self.stream.current.type == 'colon':
            next(self.stream)
            args = [None]
        else:
            node = self.parse_expression()
            if self.stream.current.type != 'colon':
                return node
            next(self.stream)
            args = [node]

        if self.stream.current.type == 'colon':
            args.append(None)
        elif self.stream.current.type not in ('rbracket', 'comma'):
            args.append(self.parse_expression())
        else:
            args.append(None)

        if self.stream.current.type == 'colon':
            next(self.stream)
            if self.stream.current.type not in ('rbracket', 'comma'):
                args.append(self.parse_expression())
            else:
                args.append(None)
        else:
            args.append(None)

        return nodes.Slice(lineno=lineno, *args)