{"ast_node_type":"variable","tokens":[{"end":59,"kind":"keyword","start":0,"text":"let"}]}
        let unresolved_kind_ty = match *closure_ty.kind() {
    pub fn closure_kind(&self, closure_ty: Ty<'tcx>) -> Option<ty::ClosureKind> {
            ty::Closure(_, args) => args.as_closure().kind_ty(),