{"ast_node_type":"variable","tokens":[{"end":88,"kind":"keyword","start":0,"text":"let"}]}
    let mut in_macro_expansion = FxIndexMap::<hir::HirFileId, Vec<Runnable>>::default();
    // In case an expansion creates multiple runnables we want to name them to avoid emitting a bunch of equally named runnables.
    let mut add_opt = |runnable: Option<Runnable>, def| {