syntax_data: {"ast_node_type":"other","tokens":[{"end":89,"kind":"keyword","start":0,"text":"format!(\"this"}]}
source_snippet:                     format!("this matches on type `{}_`", def_br_mutbl.ref_prefix_str());
context_before:                 let label_msg =
context_after:                 let mut label = MultiSpan::from(span);