syntax_data: {"ast_node_type":"other","tokens":[{"end":75,"kind":"keyword","start":0,"text":"match"}]}
source_snippet:         match self.match_impl(impl_def_id, impl_trait_header, obligation) {
context_before:         let impl_trait_header = self.tcx().impl_trait_header(impl_def_id).unwrap();
context_after:             Ok(args) => args,