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# LocalizedStringKey.StringInterpolation

Represents the contents of a string literal with interpolations
while it’s being built, for use in creating a localized string key.

```
struct StringInterpolation
```

## Topics

### Appending to an interpolation

The compiler uses these methods when interpreting string interpolations; don’t call them directly.

[`func   appendInterpolation ( _ :)`](/documentation/SwiftUI/LocalizedStringKey/StringInterpolation/appendInterpolation(_:))

Appends an attributed substring to a string interpolation.

[`appendInterpolation(_:specifier:)`](/documentation/SwiftUI/LocalizedStringKey/StringInterpolation/appendInterpolation(_:specifier:))

Appends a type, convertible to a string with a format specifier,
to a string interpolation.

[`func   appendInterpolation ( _ : format :)`](/documentation/SwiftUI/LocalizedStringKey/StringInterpolation/appendInterpolation(_:format:))

Appends the formatted representation  of a nonstring type
supported by a corresponding format style.

[`func   appendInterpolation ( _ : formatter :)`](/documentation/SwiftUI/LocalizedStringKey/StringInterpolation/appendInterpolation(_:formatter:))

Appends an optionally-formatted instance of an Objective-C subclass
to a string interpolation.

[`appendInterpolation(_:style:)`](/documentation/SwiftUI/LocalizedStringKey/StringInterpolation/appendInterpolation(_:style:))

Appends a formatted date to a string interpolation.

[`appendInterpolation(timerInterval:pauseTime:countsDown:showsHours:)`](/documentation/SwiftUI/LocalizedStringKey/StringInterpolation/appendInterpolation(timerInterval:pauseTime:countsDown:showsHours:))

Appends a timer interval to a string interpolation.

[`appendLiteral(_:)`](/documentation/SwiftUI/LocalizedStringKey/StringInterpolation/appendLiteral(_:))

Appends a literal string.

## Relationships

### Conforms To

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

---

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