syntax_data: {"ast_node_type":"other","tokens":[{"end":55,"kind":"keyword","start":0,"text":"Ty::new_closure(self.tcx,"}]}
source_snippet:                 Ty::new_closure(self.tcx, def_id, args)
context_before:                 let args = self.fold_closure_args(def_id, args);
context_after:             }