{"ast_node_type":"other","tokens":[{"end":49,"kind":"keyword","start":0,"text":"self.prove_predicate("}]}
                            self.prove_predicate(
                            let src_ty = Ty::new_fn_ptr(self.tcx(), ty::Binder::dummy(src_sig));
                                ty::ClauseKind::WellFormed(src_ty.into()),