# XO0171: `..` used more than once or not last in pattern fields

In variant and struct patterns, `..` ignores the remaining fields and must come last: `Db(msg: m, ..)`. A list pattern may contain `..` once, anywhere: `[first, .., last]`. `..` is not allowed outside list, variant, and struct patterns. See core 3.5.

## Example

```xo
enum E { Db(msg: Str, code: Int) }

fn f(e: E) -> Int {
  match e {
    Db(.., code: c) => c
  }
}
```

## Fix

```xo
enum E { Db(msg: Str, code: Int) }

fn f(e: E) -> Int {
  match e {
    Db(code: c, ..) => c
  }
}
```

Run `xo explain XO0171` for this text in a terminal, or see
[section 10.6 of the specification](../../spec/core/#106-diagnostic-codes).