{"ast_node_type":"variable","tokens":[{"end":86,"kind":"keyword","start":0,"text":"let"}]}
                        let sig = table.eagerly_normalize_and_resolve_shallow_in(sig);
                        let sig = self.expr_ty.callable_sig(table.db).expect("FnDef had no sig");
                        let fn_ptr = TyKind::Function(sig.to_fn_ptr()).intern(Interner);