---
title: "init(unsafeAddress:mutating:)"
framework: Swift
role: symbol
role_heading: Initializer
platforms: [iOS 27.0+, iPadOS 27.0+, Mac Catalyst 27.0+, macOS 27.0+, tvOS 27.0+, visionOS 27.0+, watchOS 27.0+]
path: "swift/mutableref/init(unsafeaddress:mutating:)"
---

# init(unsafeAddress:mutating:)

Unsafely initializes an instance of MutableRef using the given ‘unsafeAddress’ as the mutable reference based on the mutating lifetime of the given ‘owner’ argument.

## Declaration

```swift
init<Owner>(unsafeAddress pointer: UnsafeMutablePointer<Value>, mutating owner: inout Owner) where Owner : ~Copyable, Owner : ~Escapable
```

## Parameters

- `owner`: The owning instance that this MutableRef instance’s lifetime is based on.