---
title: "skipBack(by:)"
framework: swift
role: symbol
role_heading: Instance Method
path: "swift/utf8span/unicodescalariterator/skipback(by:)"
---

# skipBack(by:)

Move currentCodeUnitOffset to the start of the previous n scalars, without decoding them.

## Declaration

```swift
mutating func skipBack(by n: Int) -> Int
```

## Discussion

Discussion Returns the number of Unicode.Scalars skipped over, which can be fewer than n if at the start of the UTF8Span. note: O(n)