syntax_data: {"ast_node_type":"other","tokens":[{"end":77,"kind":"keyword","start":0,"text":"ty"}]}
source_snippet:             ty => panic!("closure_sig_as_fn_ptr_ty is not a fn-ptr: {ty:?}"),
context_before:             ty::FnPtr(sig_tys, hdr) => sig_tys.with(hdr),
context_after:         }