Swift 5: String.UTF16View.Index(encodedOffset: l) deprecated

Question

I'm using this code to insert hyphens into a string for better word-wrapping. With Swift 5 I get the info that

String.UTF16View.Index(encodedOffset: l)

would be deprecated. But I can not figure out the correct parameters. Any ideas?

import Foundation

extension String {

    func hyphenated(languageCode: String) -> String {
        let locale = Locale(identifier: languageCode)
        return self.hyphenated(locale: locale)
    }

    func hyphenated(locale: Locale) -> String {
        guard CFStringIsHyphenationAvailableForLocale(locale as CFLocale) else { return self }

        var s = self

        let fullRange = CFRangeMake(0, s.utf16.count)
        var hyphenationLocations = [CFIndex]()
        for (i, _) in s.utf16.enumerated() {
            let location: CFIndex = CFStringGetHyphenationLocationBeforeIndex(s as CFString, i, fullRange, 0, locale as CFLocale, nil)
            if hyphenationLocations.last != location {
                hyphenationLocations.append(location)
            }
        }

        for l in hyphenationLocations.reversed() {
            guard l > 0 else { continue }
            let strIndex = String.UTF16View.Index(encodedOffset: l)
            // insert soft hyphen:
            s.insert("\u{00AD}", at: strIndex)
            // or insert a regular hyphen to debug:
            // s.insert("-", at: strIndex)
        }

        return s
    }
}

Answer 1

l is the offset in UTF-16 code units in the string s, so you can replace

let strIndex = String.UTF16View.Index(encodedOffset: l)

by

let strIndex = s.utf16.index(s.utf16.startIndex, offsetBy: l)

or use

let strIndex = String.Index(utf16Offset: l, in: s)

which was introduced in Swift 5 with SE-0241 Deprecate String Index Encoded Offsets.