{"ast_node_type":"other","tokens":[{"end":44,"kind":"keyword","start":0,"text":"///"}]}
        /// test if expression is a null ptr
    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &hir::Expr<'_>) {
        fn is_null_ptr(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> bool {