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# AnimationFormatString.OSLogMessage

A log message that includes an animation tag.

```
@frozen struct OSLogMessage
```

## Overview

An [`AnimationFormatString.OSLogMessage`](/documentation/os/AnimationFormatString/OSLogMessage) structure contains a message that you construct from a string interpolation or string literal. This message includes an additional animation tag. Don’t create this structure directly. The system creates one automatically when you log a message using the [`os_signpost(_:dso:log:name:signpostID:_:_:)`](/documentation/os/os_signpost(_:dso:log:name:signpostID:_:_:)-nez5) function

## Topics

### Creating a Format String

[`init(stringLiteral: String)`](/documentation/os/AnimationFormatString/OSLogMessage/init(stringLiteral:))

Creates a log message using a string literal.

## Relationships

### Conforms To

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

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

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

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

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

---

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