{"ast_node_type":"variable","tokens":[{"end":60,"kind":"keyword","start":0,"text":"let"}]}
    let leading_pipe = if leading_pipe { "| " } else { "" };
pub fn or_pat(pats: impl IntoIterator<Item = ast::Pat>, leading_pipe: bool) -> ast::OrPat {
    let pats = pats.into_iter().join(" | ");