<!--
{
  "availability" : [
    "iOS: 26.0.0 -",
    "iPadOS: 26.0.0 -",
    "macCatalyst: 26.0.0 -",
    "macOS: 26.0.0 -",
    "tvOS: 26.0.0 -",
    "visionOS: 26.0.0 -",
    "watchOS: 26.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "Foundation",
  "identifier" : "/documentation/Foundation/AttributedString/Index/isValid(within:)-6wjr6",
  "metadataVersion" : "0.1.0",
  "role" : "Instance Method",
  "symbol" : {
    "kind" : "Instance Method",
    "modules" : [
      "Foundation"
    ],
    "preciseIdentifier" : "s:10Foundation16AttributedStringV5IndexV7isValid6withinSbAA013DiscontiguousB9SubstringV_tF"
  },
  "title" : "isValid(within:)"
}
-->

# isValid(within:)

Indicates whether the index is valid for use with the provided discontiguous attributed string.

```
func isValid(within text: DiscontiguousAttributedSubstring) -> Bool
```

## Parameters

`text`

A discontiguous attributed string used to validate the index.

## Return Value

`true` when the index is valid for use with the provided discontiguous attributed string; otherwise, false. An index is valid if it is both within the bounds of the discontiguous attributed string and was produced from the provided string without any intermediate mutations.

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)