{"ast_node_type":"other","tokens":[{"end":87,"kind":"keyword","start":0,"text":"desc"}]}
        desc { |tcx| "computing trait implemented by `{}`", tcx.def_path_str(impl_id) }
    query impl_trait_header(impl_id: DefId) -> Option<ty::ImplTraitHeader<'tcx>> {
        cache_on_disk_if { impl_id.is_local() }