syntax_data: {"ast_node_type":"other","tokens":[{"end":71,"kind":"keyword","start":0,"text":"visit_subpat(self,"}]}
source_snippet:                 visit_subpat(self, subpattern, &subpattern_user_tys, f)
context_before:                 let subpattern_user_tys = user_tys.push_user_type(base_user_ty);
context_after:             }