String isWellFormed() and toWellFormed()
The isWellFormed() method of strings returns a boolean indicating if the string contains any Unicode lone surrogates. The toWellFormed() method returns a new string where all lone surrogates are replaced by the Unicode replacement character.
Status
Baseline Newly Available (since 2023-10-24)
This feature is expected to reach Baseline Widely Available status on: 2026-04-24
MDN documentation
Specifications
- ECMAScript® 2026 Language Specification (#sec-string-objects), from TC39 (Ecma International).
Browser support
- Chrome 111 Released on 2023-03-07
- Chrome Android 111 Released on 2023-03-07
- Edge 111 Released on 2023-03-13
- Firefox 119 Released on 2023-10-24
- Firefox for Android 119 Released on 2023-10-24
- Safari 16.4 Released on 2023-03-27
- Safari on iOS 16.4 Released on 2023-03-27
Usage (according to Chrome Platform Status)
~6.568% of page loads. More data at chromestatus.
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