---
title: mutableBytes
framework: swift
role: symbol
role_heading: Instance Property
path: swift/mutablespan/mutablebytes
---

# mutableBytes

Construct a mutable raw span over the memory represented by this span.

## Declaration

```swift
var mutableBytes: MutableRawSpan { mutating get }
```

## Return Value

Return Value A MutableRawSpan over the memory represented by this span

## Discussion

Discussion Mutating self through this property is unsafe because it is possible to mutate a byte so as to produce an invalid bit pattern in the corresponding instance of Element.