---
title: next()
framework: swift
role: symbol
role_heading: Instance Method
path: swift/unsaferawbufferpointer/iterator/next()
---

# next()

Advances to the next byte and returns it, or nil if no next byte exists.

## Declaration

```swift
mutating func next() -> UInt8?
```

## Return Value

Return Value The next sequential byte in the raw buffer if another byte exists; otherwise, nil.

## Discussion

Discussion Once nil has been returned, all subsequent calls return nil.