alt Hacker News>The other point I've seen is that its string library is slow and very accurate.
Swift strings default to operating on grapheme clusters, which is relatively slow. But you can always choose to work with the underlying UTF-8 representation or with unicode scalars, which is fast.
The only situation where UTF-8 incurs overhead is if the String comes from some old Objective-C API that gives you a UTF-16 encoded String.
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wahnfrieden • today at 2:58 PM
Unicode scalars are not so fast. But yes working directly with UInt8/Data bytes is efficient.
That’s how I took over maintenance of SwiftSoup and made it over 10x faster according to my benchmarks. Besides various other optimizations such as reducing copying, adding indexes, etc.
> Swift strings default to operating on grapheme clusters, which is relatively slow.
The unicode-segmentation crate implements this for Rust, in case it matters for accuracy.