syntax_data: {"ast_node_type":"other","tokens":[{"end":86,"kind":"keyword","start":0,"text":"ty::FnPtr(sig_tys,"}]}
source_snippet:             ty::FnPtr(sig_tys, hdr) => ty::FnPtr(sig_tys.try_fold_with(folder)?, hdr),
context_before:             ty::FnDef(def_id, args) => ty::FnDef(def_id, args.try_fold_with(folder)?),
context_after:             ty::UnsafeBinder(f) => ty::UnsafeBinder(f.try_fold_with(folder)?),