{"ast_node_type":"variable","tokens":[{"end":29,"kind":"keyword","start":0,"text":"let"}]}
    let mut count: usize = 0;
pub fn tuple_pat(pats: impl IntoIterator<Item = ast::Pat>) -> ast::TuplePat {
    let mut pats_str = pats.into_iter().inspect(|_| count += 1).join(", ");