---
title: String.LocalizationValue.Placeholder
framework: swift
role: symbol
role_heading: Enumeration
path: swift/string/localizationvalue/placeholder
---

# String.LocalizationValue.Placeholder

An enumeration of types that can appear as a placeholder in a string interpolation.

## Declaration

```swift
enum Placeholder
```

## Overview

Overview Foundation uses this type when you create a string with the \(placeholder: type) syntax and supply an array of replacement values in a String.LocalizationOptions. Placeholders work with String initializers that take an options: parameter: init(localized:options:table:bundle:locale:comment:) init(localized:options:) init(localized:defaultValue:options:table:bundle:locale:comment:) You only use this type directly when specifying one of its enumeration cases in the placeholder syntax, like \(placeholder: .int).

## Topics

### Placeholder types

- [String.LocalizationValue.Placeholder.int](swift/string/localizationvalue/placeholder/int.md)
- [String.LocalizationValue.Placeholder.uint](swift/string/localizationvalue/placeholder/uint.md)
- [String.LocalizationValue.Placeholder.float](swift/string/localizationvalue/placeholder/float.md)
- [String.LocalizationValue.Placeholder.double](swift/string/localizationvalue/placeholder/double.md)
- [String.LocalizationValue.Placeholder.object](swift/string/localizationvalue/placeholder/object.md)

## Relationships

### Conforms To

- [Decodable](swift/decodable.md)
- [Encodable](swift/encodable.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)