---
title: "init(_:)"
framework: swift
role: symbol
role_heading: Initializer
path: "swift/uint128/init(_:)-luvl"
---

# init(_:)

Creates a new instance from the given integer.

## Declaration

```swift
init<T>(_ source: T) where T : BinaryInteger
```

## Parameters

- `source`: An integer to convert. source must be representable in this type.

## Discussion

Discussion If the value passed as source is not representable in this type, a runtime error may occur. let x = -500 as Int let y = Int32(x) // y == -500

// -500 is not representable as a 'UInt32' instance let z = UInt32(x) // Error