{"ast_node_type":"other","tokens":[{"end":47,"kind":"keyword","start":0,"text":"impl<Cx:"}]}
impl<Cx: PatCx> fmt::Debug for WitnessPat<Cx> {
/// This is best effort and not good enough for a `Display` impl.
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {