# ErrorReason
<span class="source-link">[[Source]](src/options/options.md#L89)</span>
```pony
type ErrorReason is
  (UnrecognisedOption val | MissingArgument val | InvalidArgument val | AmbiguousMatch val)
```

#### Type Alias For

* ([UnrecognisedOption](options-UnrecognisedOption.md) val | [MissingArgument](options-MissingArgument.md) val | [InvalidArgument](options-InvalidArgument.md) val | [AmbiguousMatch](options-AmbiguousMatch.md) val)

---

