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Comment by nanidin | Hacker News Reader

It says it sorts one byte at a time. I think this would break for anything not utf-8.

Seems like it should work for arbitrary byte strings (any charset, any encoding)but obviously the performance characteristics will differ because of non-uniform distribution. But that happens even in ASCII.

Yes, you’ll get something sorted based on the bytes in the string but it won’t be lexicographically correct - for example, à will be sorted after b.

This would even break UTF-8, since multi-byte characters are a thing!

How would that break anything? The strings aren't being split.

Lexicographic encoding of UTF-8 byte sequences matches lexicographic order of the sequence of Unicode code-points. So you can sort UTF-8 strings as byte strings. Not that sorting by code-points has much meaning, but you can use the Unicode collation algorithm first.

% printf "%s\n" A B | sort

% printf "%s" A B | xxd -b -c4

00000000: 11110000 10011101 10010000 10110100 ....

00000004: 11110000 10011101 10010000 10110101 ....

% printf "%s" A B | xxd -c1 -ps | sort | xxd -r -ps | xxd -b -c4

00000000: 10010000 10010000 10011101 10011101 ....

00000004: 10110100 10110101 11110000 11110000 ....

% printf "%s" A B | xxd -c1 -ps | sort | xxd -r -ps

????????

TIL, thanks. That makes sense given how the length prefixes look like but I never thought about it. I wonder if this was by chance or if the UTF-8 creator thought about it.

Indeed, and is à less than b? Not in Unicode!

UTF-8 is downward compatible to ASCII, so anything that is just a standard character (like every character in this comment) is just a byte.

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