{"ast_node_type":"variable","tokens":[{"end":109,"kind":"keyword","start":0,"text":"//"}]}
                                // Since we know it's a block, we know we can insert the `let _ = ..` without
                                // E.g. with a `|| $body` expanded from a `m!({ .. })`, we use `{ .. }`, and not `$body`.
                                // breaking the macro syntax.