# CustomPlaygroundDisplayConvertible A type that supplies a custom description for playground logging. ``` protocol CustomPlaygroundDisplayConvertible ``` ## Overview Playground logging can generate, at a minimum, a structured description of any type. If you want to provide a custom description of your type to be logged in place of the default description, conform to the `CustomPlaygroundDisplayConvertible` protocol. Playground logging generates a richer, more specialized description of core types. For example, the contents of a `String` are logged, as are the components of an `NSColor` or `UIColor`. The current playground logging implementation logs specialized descriptions of at least the following types: - `String` and `NSString` - `Int`, `UInt`, and the other standard library integer types - `Float` and `Double` - `Bool` - `Date` and `NSDate` - `NSAttributedString` - `NSNumber` - `NSRange` - `URL` and `NSURL` - `CGPoint`, `CGSize`, and `CGRect` - `NSColor`, `UIColor`, `CGColor`, and `CIColor` - `NSImage`, `UIImage`, `CGImage`, and `CIImage` - `NSBezierPath` and `UIBezierPath` - `NSView` and `UIView` Playground logging may also be able to support specialized descriptions of other types. ## Conforming to the CustomPlaygroundDisplayConvertible Protocol To add `CustomPlaygroundDisplayConvertible` conformance to your custom type, implement the `playgroundDescription` property. If your implementation returns an instance of one of the types above, that type’s specialized description is used. If you return any other type, a structured description is generated. If your type has value semantics, the `playgroundDescription` should be unaffected by subsequent mutations, if possible. If your type’s `playgroundDescription` returns an instance which itself conforms to `CustomPlaygroundDisplayConvertible`, then that type’s `playgroundDescription` will be used, and so on. To prevent infinite loops, playground logging implementations can place a reasonable limit on this kind of chaining. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)