A report from the documentation maintainer

Posted Nov 2, 2016 20:07 UTC (Wed) by nybble41 (subscriber, #55106)
In reply to: A report from the documentation maintainer by robbe
Parent article: A report from the documentation maintainer

> FWIW, I’m one of those people who are glad that we finally transcended ASCII.

I'm also glad that we're no longer restricted to ASCII filenames, but is it really too much to ask that character case be taken into account for sorting and glob pattern matching, regardless of the locale? It's not as if Unicode fails to distinguish between upper- and lower-case characters where applicable. Case sensitivity should not be a function of the encoding.

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A report from the documentation maintainer

Posted Nov 2, 2016 20:42 UTC (Wed) by bronson (subscriber, #4806) [Link] (13 responses)

Programmers may believe that ABCabc is an appropriate collation sequence, but most people expect the more traditional AaBbCc. And computers are increasingly made for most people.

A report from the documentation maintainer

Posted Nov 2, 2016 22:22 UTC (Wed) by nybble41 (subscriber, #55106) [Link] (12 responses)

Obviously there are pros and cons to each collation sequence, and ideally the shell would be configurable to use either ABCabc or AaBbCc. What I have yet to see is any good reason why the collation sequence should change just because you're working in Unicode rather than ASCII.

A report from the documentation maintainer

Posted Nov 2, 2016 23:25 UTC (Wed) by mstone_ (subscriber, #66309) [Link] (11 responses)

It doesn't change with unicode vs ASCII, it changes with natural sorting vs byte sorting. You can set a locale which is not unicode but which does reflect long established rules of dictionary sorting. ASCII byte sorting is a bug. It leads to behavior which is simply incorrect according to various language's conventions for ordering text. It was introduced because it was feasible on the computers of the 1960s, not because it was correct. In recognition of the fact that some people wrote code which was bug-dependent, the C locale was introduced to lock everything to 1980. Some people cling to that as the pinnacle of human achievement and become increasingly angry as the world moves on and fewer and fewer people see things the same way. (Literally: their program output is not the same.) Be that as it may, most of the world (especially the vast majority of people who couldn't write their own name with plain ASCII and the shortcut byte-ordering it facilitated) isn't going to look back.

A report from the documentation maintainer

Posted Nov 3, 2016 15:45 UTC (Thu) by nybble41 (subscriber, #55106) [Link] (10 responses)

> It doesn't change with unicode vs ASCII, it changes with natural sorting vs byte sorting.

Exactly as I've been saying. And yet, enabling Unicode *character encoding* in your environment somehow implies to the shell that you want so-called "natural" sorting rather than traditional byte sorting, unless you take further steps to override LC_COLLATE. These are unrelated topics and there is no good reason for a change in character encoding to affect the sort order, or vice-versa.

There is nothing "unnatural" about sorting uppercase characters first to match the traditional behavior of the shell. This is no different from the common option to sort directories before regular files. For that matter there is nothing "unnatural" about sorting filenames as the byte strings they actually are, regardless of encoding, rather than by their locale-specific decoding into text. Only the byte-strings are guaranteed to be uniform system-wide; the text presented to the user depends on the current environment.

> especially the vast majority of people who couldn't write their own name with plain ASCII and the shortcut byte-ordering it facilitated

Again, separate issues. Nothing about byte-order sorting precludes the use of Unicode character encoding in filenames.

Anyway, this is getting rather far off-topic. The subject was glob patterns and the dubious wisdom of matching characters not specified by the user. If the user writes the glob [A-Z] that should be read as "the uppercase letters from A to Z", not "all letters except lowercase z" (using a range of letters in "natural" sort order) or "all letters" (using case-insensitive comparison). A user who went to the trouble of writing [A-Z] in uppercase obviously didn't intend to match [a-z]. Sort order is, for the most part, a matter of preference and not correctness; redefining the filenames which match a given glob pattern carries a much larger risk of data-loss.

As for the earlier objection that only a programmer would view things this way... the shell is a programming language! Anyone writing commands at the shell prompt is a programmer. If you want an interface designed for non-programmers, there are any number of GUI file managers and program launchers available.

A report from the documentation maintainer

Posted Nov 3, 2016 15:56 UTC (Thu) by farnz (subscriber, #17727) [Link] (3 responses)

But "the uppercase letters from A to Z" is locale-dependent. For a Pole, that includes Ó. For a Swede, it does not.

Basically, the moment you go beyond the user specifying all characters that they're interested in, you're making locale assumptions; whether that be because you're guessing at case, or because you're looking at a range and the user expects the range to include the characters they would include in that range.

A report from the documentation maintainer

Posted Nov 4, 2016 0:09 UTC (Fri) by lsl (guest, #86508) [Link] (2 responses)

There's always Unicode code point order, where A-Z is well-defined without respect to locale. UTF-8 has the nice property to sort that way using a simple strcmp-based comparator.

Sure, it isn't the order you'd see in a good old telephone book, but at least it's simple and predictable.

A report from the documentation maintainer

Posted Nov 4, 2016 9:55 UTC (Fri) by farnz (subscriber, #17727) [Link] (1 responses)

That's the problem, though - there are several non-ambiguous but arbitrary orderings (Polish alphabet, Swedish alphabet, English alphabet, French alphabet, Unicode code point etc). The machine can't (definitionally, as they conflict) give you all reasonable orderings at once; historically (1970s and 1980s) we handled this by saying that the ordering used in English is the One True Ordering, and anyone who thinks in another language can learn the One True Language. Modern machines can do better (and should, IMO).

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Posted Nov 5, 2016 1:19 UTC (Sat) by lsl (guest, #86508) [Link]

> Modern machines can do better (and should, IMO).

I'm not convinced. Software is buggy and crappy enough already even without supporting a thousand different ways to sort a directory listing. The machines can do better, but programmers apparently can't.

A report from the documentation maintainer

Posted Nov 3, 2016 16:22 UTC (Thu) by mstone_ (subscriber, #66309) [Link] (5 responses)

You keep saying things that don't make sense. Using unicode character encoding doesn't imply anything. Yes they are unrelated topics, but you keep conflating them for some reason. The implication comes not from the character encodeing, but from the user specifying the language that they want to use, including that language's sorting rules. What you seem to want is for the natural language sorting rules to be arbitrarily ignored (always?) because you want to make things easier for the programmer in one particular case. (Similarly, some people want program output to be exactly as it was in 1980 rather than translated for the user because it makes parsing the output easier--another reason we have the C locale.) I guess you haven't had users complain when things are byte order sorted and they want to see things sorted in a way that makes sense for humans instead. (This is quite a common complaint, and lazy programmers often brush it off as unimportant even though it's quite important to the users.) At any rate, the shell isn't a programming language, it's a user interface. Yes, it tries to be both, and that's why it's both a lousy language and a lousy interface. It has knobs you can fiddle to make it do whatever it is you want. The fact that you have to fiddle with a bunch of knobs is part of why it's a lousy language. If you don't like this, it's more productive to choose a different language than to rail against reality. Specifically you need something with better defined semantics for pattern matching, probably something with the knobs in the API call itself rather than a bunch of environment variables which alter the semantics in unexpected and non-obvious ways. Another option is to just force the locale to C at the top of your script and explain to any users that you just can't be bothered to care about their language preference.

A report from the documentation maintainer

Posted Nov 3, 2016 19:07 UTC (Thu) by nybble41 (subscriber, #55106) [Link] (4 responses)

> The implication comes not from the character encodeing, but from the user specifying the language that they want to use, including that language's sorting rules.

The instructions provided for setting the character encoding, and the defaults for systems configured to use UTF-8, always seem to include the language as well as the character encoding. This bundling of language and encoding and collation and other preferences into a single global setting is the root of the problem. The same environment variable controls both, unless you set yet another variable to selectively override the sorting rules. It doesn't make sense to use the same settings everywhere, and pattern-matching in the shell programming language is one of those areas where a dependency on the current locale makes no sense.

The fact that the user wants to see messages in English (or whatever language) and use UTF-8 for character encoding should not be taken to imply that they want to change the way the shell expands glob patterns.

As I said before, collation order for user-visible output is not really the point. Sometimes the correctness of a script does depend on the sort order internally (such as *.d directories), but typically the files involved are defined to start with ASCII digits and case issues consequently do not apply (given reasonable locale definitions). Personally I would be content with an option to sort by a file type, case, filename triplet which otherwise followed the locale-specific rules. Absent that option, byte-order sorting with LC_COLLATE=C gives the desired behavior in 99.9% of the cases I am ever likely to encounter. YMMV.

> At any rate, the shell isn't a programming language, it's a user interface.

Shell is a user interface in the same sense as any programming language: a user interface designed for use by programmers. It's ridiculous to claim that it isn't a programming language, since significant fraction of the programs on most Unix systems are written in it. By percentage of commands executed it's a programming language first, with interactive use as a distant second.

> If you don't like this, it's more productive to choose a different language than to rail against reality. Specifically you need something with better defined semantics for pattern matching, probably something with the knobs in the API call itself rather than a bunch of environment variables which alter the semantics in unexpected and non-obvious ways.

What do you think this thread was about? This "better language" you suggest is shell, as it existed before glob patterns became locale-aware and thus context-dependent and dangerously unpredictable. Now the only safe way to write a Bash shell script with glob patterns is by setting the globasciiranges option within the script. For system scripts which can't be fixed the only option is to force LC_COLLATE=C.

A report from the documentation maintainer

Posted Nov 3, 2016 20:05 UTC (Thu) by mstone_ (subscriber, #66309) [Link] (3 responses)

> The instructions provided for setting the character encoding, and the defaults for systems configured to use UTF-8, always seem to include the language as well as the character encoding.

You continue to go on about character encoding, which has nothing to do with this. I don't fully understand why you keep bringing it up. If you byte sort purely english language text using UTF-8 encoding it's exactly the same as byte sorting purely english text using ASCII encoding. But real people don't want their output byte sorted, they want it sorted in a way that's sensible to them.

> The fact that the user wants to see messages in English (or whatever language) and use UTF-8 for character encoding should not be taken to imply that they want to change the way the shell expands glob patterns.

Clearly it should, that's the reality. You want a different reality than one which we inhabit. It's also a good thing that people who use languages other than english can use character classes which include characters from their language, which they couldn't do in the 1980s. And if you still want 1980s semantics, tada, they're still there by turning a knob.

> Shell is a user interface in the same sense as any programming language: a user interface designed for use by programmers. It's ridiculous to claim that it isn't a programming language, since significant fraction of the programs on most Unix systems are written in it. By percentage of commands executed it's a programming language first, with interactive use as a distant second.

Most system commands are now written in other, better languages. The majority of people using a unix command line today interact via the shell but don't program using it. That's for the best. In my bin & sbin right now I have:
1236 compiled
238 shell
163 perl
83 bash
71 python
11 ruby
1 tcl
1 php

Looking at the shell scripts they're mostly either trivial, or at least 15 years old. 100 of them are less than 50 lines. A couple are cheats, only using the shell to launch some other interpreter. As far as I can tell from a quick glance, none of them use the critical "remove-files-with-a-glob-character-class" capability you're so stuck on. The longest are 1-2k LOC and date from the early to mid 90s. So yeah, some people program in it, mostly trivial scripts which avoid dealing with corner cases, and mostly as a legacy capability. I stand by my assertion that the majority of users' interaction with the shell is as an interface with some automation capabilities. I suspect that was always true, and that the number of people who copied around cool snippits of .profile was much higher than the number of people who actually created them (that's certainly my recollection of the cs lab).

> What do you think this thread was about? This "better language" you suggest is shell, as it existed before glob patterns became locale-aware and thus context-dependent and dangerously unpredictable.

I have no idea what this thread is about at this point. You keep bringing up character encodings for some reason, and asserting that the shell is something other than what it actually is. I started the thread with the assertion that upper casing filenames to make them come first is something that's pretty irrelevant to anyone except a few wild-eyed people who haven't kept up with the reality of modern systems and then you proceeded to demonstrate my point. Yeah, some tricks that worked 30 years ago don't work anymore (like uppercasing filenames to make them come first). New things have come along that most people are pretty happy about (I'm personally happy taking advantage of the fact that I can run interpreters and libraries that aren't constrained by 1970s or 80s era hardware limitations). You can either continue to complain that things changed or acknowledge that today's user has a different experience from one 30 years ago and do things in a way that make sense in a modern context.

A report from the documentation maintainer

Posted Nov 3, 2016 22:37 UTC (Thu) by bronson (subscriber, #4806) [Link]

> and do things in a way that make sense in a modern context.

Where "modern context" refers to the centuries-old practice of case-insensitive collation. :)

Did case-sensitive collation even exist before punchcards?

A report from the documentation maintainer

Posted Nov 14, 2016 18:27 UTC (Mon) by Wol (subscriber, #4433) [Link] (1 responses)

> If you byte sort purely english language text using UTF-8 encoding it's exactly the same as byte sorting purely english text using ASCII encoding.

Except that if you try that with the purely ENGLISH word "Noël", you can't sort that in ASCII :-)

Cheers,
Wol

A report from the documentation maintainer

Posted Nov 14, 2016 20:23 UTC (Mon) by bronson (subscriber, #4806) [Link]

You can absolutely byte sort it.

If you're saying that's inadequate for most people then, agreed, but that's been stated on this thread a few times already...

A report from the documentation maintainer

Posted Nov 2, 2016 21:28 UTC (Wed) by farnz (subscriber, #17727) [Link] (20 responses)

It's not too much to ask, but it's a hard problem. To take a couple of examples, using == for "insensitive comparison":

Should ß == SS? In a German filename, the answer is "yes", because ß is just a different way to write ss; in an English filename, however, it's a symbol, not a letter.
Should a == ä? In an English or Afrikaans filename, yes; the diacritic is a pronunciation guide only. In a Swedish filename, no, because ä is a different letter to a.
Should i == I? In most Latin alphabet languages, yes; lowercase I is dotted, uppercase i is not. In Turkish, however, i's uppercase form is İ, not I.

Unicode makes a decent stab at a solution (section 5.18), but then explicitly calls out Lithuanian and Turkic languages as cases where the default algorithm will not include something that users expect it to include; further, the Unicode solution is based on the principle that it's better for the algorithm to match things it shouldn't, than it is for it to miss things it should match. Thus, an English user will be surprised that the glob S* matches ß, but that's better than a German user being surprised when s* does not match ß. Similarly, a Swede is going to be surprised when nä* matches nävi, specifically so that an English user isn't surprised when na* doesn't match nävi.

A report from the documentation maintainer

Posted Nov 2, 2016 22:44 UTC (Wed) by nybble41 (subscriber, #55106) [Link] (1 responses)

> ... the Unicode solution is based on the principle that it's better for the algorithm to match things it shouldn't, than it is for it to miss things it should match.

That's debatable, and it really depends on what the glob pattern is being used for. When deleting files, for example, it would generally be better to match conservatively so that you don't remove files which the user didn't expect to match. In most cases it's much easier to clean up any files which were missed than it is to restore ones which were unexpectedly removed. The same would apply to any operation which modified files in place (e.g. perl -i).

Personally, I just set LC_COLLATE=C and compare all strings bytewise--which does not preclude the use of Unicode filenames. I find this far less surprising than any of the locale-specific options, and think it would be a safer default, especially for scripts. Interactively, absent some indication of the user's intent, perhaps the shell should evaluate the glob pattern both ways and generate an error if the results do not agree.

A report from the documentation maintainer

Posted Nov 2, 2016 23:13 UTC (Wed) by mstone_ (subscriber, #66309) [Link]

The solution here is simply not to blindly delete files using glob patterns. If you need this for some reason you'd darn well better set your locale to C, but you should probably just come up with a safer solution.

A report from the documentation maintainer

Posted Nov 2, 2016 22:54 UTC (Wed) by nybble41 (subscriber, #55106) [Link] (1 responses)

> It's not too much to ask, but it's a hard problem.

As an addendum to my previous comment, the examples given here support the argument that *case-insensitive* comparison presents difficulties above and beyond case-sensitive comparison of Unicode strings. This would make traditional case-sensitive glob matching and sorting easier to implement than the current case-insensitive behavior. "Should ß == SS?" No, the first is lowercase and the second is uppercase. (Of course, you still have to deal with the question of whether ß == ss.)

A report from the documentation maintainer

Posted Nov 3, 2016 9:35 UTC (Thu) by farnz (subscriber, #17727) [Link]

The other trouble is that any human-friendly comparison function presents difficulties for the machine - too much of what's "correct" depends on your cultural norms. For example, I've known native Arabic speakers who simply could not get their heads around the idea that English has 5 different short vowel sounds, and that the difference between "nit" and "net" is significant (because the short vowel modifies the preceding consonant) - to their eyes, both were reasonable ways to write what in Arabic would be nt (as Arabic writing does not include short vowel sounds by default).

The brains of the squishy bag of meat in control of the computer are weird places - while I don't think the difficulty is insurmountable, I don't think it's a trivial problem to solve, either.

A report from the documentation maintainer

Posted Nov 3, 2016 22:12 UTC (Thu) by tao (subscriber, #17563) [Link]

Swedish standardised sorting actually treats V = W, which annoys the hell out of me, seeing as my last name starts with a W :)

A report from the documentation maintainer

Posted Nov 4, 2016 10:10 UTC (Fri) by tdz (subscriber, #58733) [Link] (14 responses)

> Should ß == SS? In a German filename, the answer is "yes", because ß is just a different way to
> write ss;

Actually no, because the result would be pronounced differently, or even be a different word. Double-s is just the workaround for scripts that don't have 'ß'.

A report from the documentation maintainer

Posted Nov 4, 2016 10:14 UTC (Fri) by farnz (subscriber, #17727) [Link] (13 responses)

So what is the correct capitalisation of "groß"? I can't find a capital eszet in normal use, and the beginners guide I'm consulting says that "groß" would capitalise as "GROSS". For that to hold true for a case-insensitive comparison, the filename "groß ding" has to compare equal to the filename "GROSS DING", otherwise the comparison is not fully case-insensitive; and on the case insensitive locale-aware OSes I've tried, that indeed holds true.

A report from the documentation maintainer

Posted Nov 4, 2016 10:25 UTC (Fri) by tao (subscriber, #17563) [Link] (4 responses)

You mean "ẞ" U+1E9E LATIN CAPITAL LETTER SHARP S?

A report from the documentation maintainer

Posted Nov 4, 2016 11:23 UTC (Fri) by idrys (subscriber, #4347) [Link]

I have not seen much (if anything at all) of the capital ß in the wild - it's mostly capitalized as the previous poster noted.

(With all the fun of 'in Maßen' (i.e. not too much) vs. 'in Massen' (a lot) - although the reforms inflicted upon German writing in the last years mean that most people are confused anyway...)

A report from the documentation maintainer

Posted Nov 4, 2016 11:42 UTC (Fri) by farnz (subscriber, #17727) [Link] (2 responses)

It exists, yes, but all the references I can find (as a beginner in the language, not a native speaker nor resident in a German-speaking country) tell me that the use of U+1E9E is for things like advertising, where you're doing the "shouting caps" emphasis trick - thus, where an English advert might say "BIG..." the German equivalent advert would use "GROẞ" to indicate that the caps are not "real" capitals, they're shouting.

In normal writing, though, everything seems to use SS as the capital form of ß.

A report from the documentation maintainer

Posted Nov 7, 2016 18:16 UTC (Mon) by JanC_ (guest, #34940) [Link] (1 responses)

That's at least partially also because “ẞ” isn't on German typewriters, (traditional) computer keyboards, etc.

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Posted Nov 8, 2016 9:40 UTC (Tue) by anselm (subscriber, #2796) [Link]

The codepoint for the uppercase “ß” was added to Unicode as a sort of precaution and to make life easier for people implementing case conversion routines. In Germany, in spite of this, uppercase “ß” isn't actually being used in practice, and in fact there is no official agreement or rule as to what the glyph should even look like (although people keep throwing around “ẞ” as if that was some sort of gospel). It would be reasonable to render U+1E9E as “SS” except for the ambiguity with “in Maßen/Massen”, or as “ß” (i.e., exactly like the lowercase “ß”) except for the bad typography of having a lowercase letter in the middle of a bunch of uppercase ones.

Generally, according to the new German orthography rules we're now supposed to write “ß” after a long vowel (or diphthong) and “ss” after a short vowel. This is not the worst part of the orthography reform but the uppercase-“ß” issue remains largely unresolved.

A report from the documentation maintainer

Posted Nov 7, 2016 9:11 UTC (Mon) by tdz (subscriber, #58733) [Link] (7 responses)

Hi,

as the other commenter points out, there exists a symbol and a code to display it. But even being a native speaker, this discussion is actually the first place I've ever seen it. :D

You can use double-s in place of ß in capitalization and that's what people usually do. I've also seen ß not being capitalized; GROß in your example. ß won't ever appear at the beginning of words, so there no 'natural' use case for capital-ß. I'm not sure if many people are aware that it exists.

A report from the documentation maintainer

Posted Nov 7, 2016 10:08 UTC (Mon) by farnz (subscriber, #17727) [Link] (6 responses)

Aha, someone who can actually answer the underlying question for me!

Would you expect a case-insensitive equality operator to have "groß" == "gross" == "GROSS" == "GROß" == "GROẞ" (which the case-insensitive OS I've played with chooses to do in a German locale)?

Put differently, would you expect that if you searched for "groß" in a text document, you would not find matches for "GROSS" but would for "GROß"? Equally, if you searched a text document for "GROSS", would you expect to see matches for "groß", or only for "gross" in a case-insensitive search?

A report from the documentation maintainer

Posted Nov 7, 2016 10:27 UTC (Mon) by johill (subscriber, #25196) [Link] (4 responses)

I'm in the same situation as tdz, being a native German speaker and never having seen the ẞ (upper-case) before. I actually appreciate if ss ends up being equivalent to ß in all cases, for multiple reasons:

sometimes I don't have German keyboard settings available immediately, making it awkward to enter ß
a document may use old or new orthography, so words like "Fluss" (river; this is the currently correct spelling) may be spelled as "Fluß" (old spelling)
when spelled in headings/etc., "SS" will frequently be used to replace "ß"

So I'd argue that treating things as in your example ("groß" == "gross" == "GROSS" == "GROß" == "GROẞ") is helpful.

A report from the documentation maintainer

Posted Nov 7, 2016 11:20 UTC (Mon) by idrys (subscriber, #4347) [Link] (3 responses)

(native speaker here as well)

While this matching helps with words that can simply be written in two ways, I'd be rather surprised to get a match for a different word (like in Maßen vs. in Massen). And I think the new orthography is, for the most part, horrible (it emphasized writing over reading while neglecting that you know what you're writing but your reader doesn't). But adherents of the old orthography will die out over time anyway :/

A report from the documentation maintainer

Posted Nov 7, 2016 13:45 UTC (Mon) by farnz (subscriber, #17727) [Link] (2 responses)

Hmm. Are you saying that, when doing a case-insensitive match, you'd really want the computer to be aware of the intended dictionary word? So that a search for "groß" matches all of "GROSS", "groß" and "gross" (leaving your human intelligence to determine which ones are "good" matches), while a search for "maßen" should match "Maßen" but not "MASSEN" or "Massen", because "Maßen" and "Massen" are different words? Or is there an underlying rule that I'm not seeing (something like "Maßen" should match "MASSEN" as an all-caps Maßen and "maßen" as missing the initial capital, but not "Massen" or "massen" because the casing rules let you see that ss was deliberate, not the result of round-tripping through upper case back to lower case)?

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Posted Nov 7, 2016 14:30 UTC (Mon) by idrys (subscriber, #4347) [Link] (1 responses)

I'd prefer to not match eszet vs. double-s at all, generally. I understand and to a degree follow the reasoning, but I think it would cause more confusion than not. (And your example neatly illustrates this; too much side-knowledge required.)

I _could_ imagine an exception for eszet vs. upper-case double-s, but I'd be surprised if 'grep -i maßen' would find MASSEN as well... (And what about 'SZ' as a capitalization for 'ß'? It is now extremely uncommon, but I've seen this in documents up to the mid-20th century.)

[As an aside, old documents are sometimes inconsistent for eszet vs. double-s in people's names as well, as they sometimes capitalized names and sometimes not, so this is not a new issue. We are not 100% sure what the family name on my mother's side is for that reason. Oh well...]

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Posted Nov 7, 2016 16:52 UTC (Mon) by mathstuf (subscriber, #69389) [Link]

FYI, there also exist ligature codepoints like `ﬁ` would need to be split apart on uppercase.

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Posted Nov 10, 2016 14:39 UTC (Thu) by tdz (subscriber, #58733) [Link]

These are all different words, so they should probably not compare equal by default. Having the option of treating ß and ss that same could be useful, though. OTOH I never had this problem in practice.

In English, people sometimes (frequently?) confuse "its" and "it's". Treating them the same in text searches seems a comparable use case.

I thought about your question about ß in capital-letter advertising messages, but I can't remember having seen that anywhere. I could imagine that advertisers avoid using ß and ss in capital letters, because it doesn't look good either way.