---
title: "formIndex(_:offsetBy:limitedBy:)"
framework: swift
role: symbol
role_heading: Instance Method
path: "swift/flattensequence/formindex(_:offsetby:limitedby:)"
---

# formIndex(_:offsetBy:limitedBy:)

## Declaration

```swift
func formIndex(_ i: inout FlattenSequence<Base>.Index, offsetBy n: Int, limitedBy limit: FlattenSequence<Base>.Index) -> Bool
```