{"ast_node_type":"variable","tokens":[{"end":49,"kind":"keyword","start":0,"text":"let"}]}
    let gate = find_gated_cfg(|sym| sym == name);
pub fn try_gate_cfg(name: Symbol, span: Span, sess: &Session, features: Option<&Features>) {
    if let (Some(feats), Some(gated_cfg)) = (features, gate) {