{"ast_node_type":"other","tokens":[{"end":52,"kind":"keyword","start":0,"text":"pats!(@ctor($($args)*,"}]}
        pats!(@ctor($($args)*, idx:$idx) $($rest)*);
    (@fields(idx:$_idx:expr, $($args:tt)*) , .$idx:ident : $($rest:tt)*) => {{
    }};