{"ast_node_type":"variable","tokens":[{"end":33,"kind":"keyword","start":0,"text":"let"}]}
        let tcx = TyCtxt { gcx };
    pub fn new(gcx: &'tcx GlobalCtxt<'tcx>) -> Self {
        ImplicitCtxt { tcx, query: None, query_depth: 0, task_deps: TaskDepsRef::Ignore }