{"ast_node_type":"function","tokens":[{"end":88,"kind":"keyword","start":0,"text":"fn"}]}
    fn append_local_to_string(&self, local: Local, buf: &mut String) -> Result<(), ()> {
    /// a name, or its name was generated by the compiler, then `Err` is returned
        let decl = &self.body.local_decls[local];