{"ast_node_type":"other","tokens":[{"end":61,"kind":"keyword","start":0,"text":"//"}]}
                // the ':block' matcher does not support them
                // While a block *expression* may have attributes (e.g. `#[my_attr] { ... }`),
                Ok(ParseNtResult::Block(self.collect_tokens_no_attrs(|this| this.parse_block())?))