{"ast_node_type":"variable","tokens":[{"end":79,"kind":"keyword","start":0,"text":"let"}]}
            let index = bx.context.new_rvalue_from_long(bx.i32_type, i as i64);
        for i in 0..in_len {
            mask_types.push(bx.context.new_field(None, bx.i32_type, "m"));