ICU-23307 Space-sensitive UnicodeSet string literals

[eggrobin]

Checklist

• Required: Issue filed: ICU-23307
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[eggrobin]

Somehow this is affecting Han-Latin/Names; Latin-Bopomofo, even though neither appears to contain string literals in UnicodeSets.

[eggrobin]

Latin-NumericPinyin.xml:

($tone) ( [i o n u {o n} {n g}]) → $2 &Pinyin-NumericPinyin($1);

Whyyy??!

[eggrobin]

de-ASCII also does this:

$AE = [Ä {A \u0308}];
$OE = [Ö {O \u0308}];
$UE = [Ü {U \u0308}];

[ä {a \u0308}] → ae;
[ö {o \u0308}] → oe;
[ü {u \u0308}] → ue;

and blt-fonipa-t-blt:

$DIGRAPHS = [{ꪹ  ꪸ} {ꪹ  ꪷ} {ꪹ ꪱ}];

These seem to be the only users of space-insensitivity of string literals.

[macchiati]

An artifact, that we just never noticed before the change

…

On Fri, Jan 9, 2026, 09:30 Robin Leroy ***@***.***> wrote: *eggrobin* left a comment (unicode-org/icu#3839) <#3839 (comment)> Latin-NumericPinyin.xml: ($tone) ( [i o n u {o n} {n g}]) → $2 &Pinyin-NumericPinyin($1); Whyyy??! — Reply to this email directly, view it on GitHub <#3839 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACJLEMC3UQT5PIQVFD2URAL4F7QVBAVCNFSM6AAAAACRGSRVNOVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTOMRZHEYDMMRSGU> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[eggrobin]

An artifact, that we just never noticed before the change

I added something to the CLDR-design agenda. (Not sure I can make it Monday, I expect this week to be chaotic—I am moving Friday—, but I’m sure you have enough context to discuss this topic.)