# M0109 switch misses cases (/docs/diagnostics/codes/m0109)

A value added to the enum later then goes unnoticed.

## The mistake and the fix [#the-mistake-and-the-fix]

<div className="code-pair">

```go title="The mistake"
type Color int
const (Red Color = iota; Green; Blue)

switch c {
case Red, Green:
}
```

```go title="Fixed"
switch c {
case Red, Green:
case Blue: // [!code highlight]
	// handled, or nothing to do // [!code highlight]
}
```

</div>

## The fix [#the-fix]

Handle the missing values, add a default clause, or write //exhaustive:ignore on the line before the switch. marmot fix adds the missing cases with empty bodies, which keeps the behavior.

See also [all error codes](/docs/diagnostics/codes) and [marmot explain](/docs/commands/explain).