{"ast_node_type":"variable","tokens":[{"end":73,"kind":"keyword","start":0,"text":"let"}]}
            let res = self.typeck_results().qpath_res(qpath, pat.hir_id);
        if let PatKind::Struct(ref qpath, fields, _) = pat.kind {
            let adt = self.typeck_results().pat_ty(pat).ty_adt_def().unwrap();