{"ast_node_type":"variable","tokens":[{"end":97,"kind":"keyword","start":0,"text":"let"}]}
    let Some(sig) = tcx.fn_sig(def_id).instantiate(tcx, &[self_ty.into()]).no_bound_vars() else {
    let span = tcx.def_span(def_id);
        span_bug!(span, "FnPtr::addr with bound vars for `{self_ty}`");