{"ast_node_type":"variable","tokens":[{"end":77,"kind":"keyword","start":0,"text":"if"}]}
                if let Some((lang_item, _)) = hir::lang_items::extract(attrs)
                // `extern` declarations and `#[track_caller]` would alter their ABI.
                    && let Some(item) = hir::LangItem::from_name(lang_item)