---
title: UnfoldFirstSequence
framework: swift
role: symbol
role_heading: Type Alias
path: swift/unfoldfirstsequence
---

# UnfoldFirstSequence

The return type of sequence(first:next:).

## Declaration

```swift
typealias UnfoldFirstSequence<T> = UnfoldSequence<T, (T?, Bool)>
```

## See Also

### Type Aliases

- [UnfoldSequence.Iterator](swift/unfoldsequence/iterator.md)