syntax_data: {"ast_node_type":"variable","tokens":[{"end":48,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:                 if let Some(message) = message {
context_before:                     tcx.get_attr(def_id, sym::rustc_reservation_impl).and_then(|a| a.value_str());
context_after:                     debug!(