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# CVAttachmentKeyDefinitionWithDefault

Associates a raw attachment key with a default value and preferred propagation mode.

```
struct CVAttachmentKeyDefinitionWithDefault<ModePreference, Value> where ModePreference : CVAttachmentModePreference, Value : CVAttachmentValueRepresentable, Value : Equatable, Value : Sendable
```

## Topics

### Initializers

[`init(String, default: Value)`](/documentation/CoreVideo/CVAttachmentKeyDefinitionWithDefault/init(_:default:))

### Instance Properties

[`var defaultValue: Value`](/documentation/CoreVideo/CVAttachmentKeyDefinitionWithDefault/defaultValue)

[`var rawValue: String`](/documentation/CoreVideo/CVAttachmentKeyDefinitionWithDefault/rawValue)

## Relationships

### Conforms To

[`Hashable`](/documentation/Swift/Hashable)

[`Sendable`](/documentation/Swift/Sendable)

[`Equatable`](/documentation/Swift/Equatable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

---

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