---
title: "init(literalCapacity:interpolationCount:)"
framework: swift
role: symbol
role_heading: Initializer
path: "swift/stringinterpolationprotocol/init(literalcapacity:interpolationcount:)"
---

# init(literalCapacity:interpolationCount:)

Creates an empty instance ready to be filled with string literal content.

## Declaration

```swift
init(literalCapacity: Int, interpolationCount: Int)
```

## Parameters

- `literalCapacity`: The approximate size of all literal segments combined. This is meant to be passed to String.reserveCapacity(_:); it may be slightly larger or smaller than the sum of the counts of each literal segment.
- `interpolationCount`: The number of interpolations which will be appended. Use this value to estimate how much additional capacity will be needed for the interpolated segments.

## Discussion

Discussion Don’t call this initializer directly. Instead, initialize a variable or constant using a string literal with interpolated expressions. Swift passes this initializer a pair of arguments specifying the size of the literal segments and the number of interpolated segments. Use this information to estimate the amount of storage you will need.