# invalid_deprecated_mixin_annotation

> Details about the invalid_deprecated_mixin_annotation diagnostic produced by the Dart analyzer.



_The annotation '@Deprecated.mixin' can only be applied to classes._

## Description

The analyzer produces this diagnostic when the `@Deprecated.mixin`
annotation is applied to a declaration that isn't a mixin class.

## Example

The following code produces this diagnostic because the annotation is on a
non-mixin class:

```dart
@[!Deprecated.mixin!]()
class C {}
```

## Common fixes

Remove the annotation:

```dart
class C {}
```

