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# Date.FormatString.StringInterpolation

```
struct StringInterpolation
```

## Topics

### Initializers

[`init(literalCapacity: Int, interpolationCount: Int)`](/documentation/Foundation/Date/FormatString/StringInterpolation/init(literalCapacity:interpolationCount:))

### Instance Methods

[`func appendInterpolation(cyclicYear: Date.FormatStyle.Symbol.CyclicYear)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(cyclicYear:))

[`func appendInterpolation(day: Date.FormatStyle.Symbol.Day)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(day:))

[`func appendInterpolation(dayOfYear: Date.FormatStyle.Symbol.DayOfYear)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(dayOfYear:))

[`func appendInterpolation(dayPeriod: Date.FormatStyle.Symbol.DayPeriod)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(dayPeriod:))

[`func appendInterpolation(era: Date.FormatStyle.Symbol.Era)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(era:))

[`func appendInterpolation(hour: Date.FormatStyle.Symbol.VerbatimHour)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(hour:))

[`func appendInterpolation(minute: Date.FormatStyle.Symbol.Minute)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(minute:))

[`func appendInterpolation(month: Date.FormatStyle.Symbol.Month)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(month:))

[`func appendInterpolation(quarter: Date.FormatStyle.Symbol.Quarter)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(quarter:))

[`func appendInterpolation(second: Date.FormatStyle.Symbol.Second)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(second:))

[`func appendInterpolation(secondFraction: Date.FormatStyle.Symbol.SecondFraction)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(secondFraction:))

[`func appendInterpolation(standaloneMonth: Date.FormatStyle.Symbol.StandaloneMonth)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(standaloneMonth:))

[`func appendInterpolation(standaloneQuarter: Date.FormatStyle.Symbol.StandaloneQuarter)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(standaloneQuarter:))

[`func appendInterpolation(standaloneWeekday: Date.FormatStyle.Symbol.StandaloneWeekday)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(standaloneWeekday:))

[`func appendInterpolation(timeZone: Date.FormatStyle.Symbol.TimeZone)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(timeZone:))

[`func appendInterpolation(week: Date.FormatStyle.Symbol.Week)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(week:))

[`func appendInterpolation(weekday: Date.FormatStyle.Symbol.Weekday)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(weekday:))

[`func appendInterpolation(year: Date.FormatStyle.Symbol.Year)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(year:))

[`func appendInterpolation(yearForWeekOfYear: Date.FormatStyle.Symbol.YearForWeekOfYear)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendInterpolation(yearForWeekOfYear:))

[`func appendLiteral(String)`](/documentation/Foundation/Date/FormatString/StringInterpolation/appendLiteral(_:))

## Relationships

### Conforms To

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

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

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

---

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