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

# next()

Produces the next element in the prefix sequence.

## Declaration

```swift
mutating func next() async rethrows -> Base.Element?
```

## Discussion

Discussion Until reaching the number of elements to include, this iterator calls next() on its base iterator and passes through the result. After reaching the maximum number of elements, subsequent calls to next() return nil.