I thought this was going to be about adding or subtracting 32. Old school.
I do hope you mean bitwise "addition" and "subtraction" -- (c => c&0xdf) or (c => c|0x20)
A popular but wrong way to convert a string to uppercase or lowercase
161–170 of 272 posts
Re: A popular but wrong way to convert a string to uppercase or lowercase
#162As always, Raymond is right. (And as usually, I could guess it's him before even clicking the link.) That said, 99% time when doing upper- or lowercase operation you're interested just in the 7-bit ASCII range of characters. For the remaining 1%, there's ICU library. Just like Raymond Chen mentioned.
> That said, 99% time when doing upper- or lowercase operation you're interested just in the 7-bit ASCII range of characters. I think it's more the exact opposite. The only times I'm dealing with 7-bit ASCII is for internal identifiers like variable names or API endpoints. Which is a lot of the time, but I can't ever think of when I've needed my code to change their case. It might literally be never. On the other han…
> Which are never in ASCII because this isn't 1990.
This is a very silly statement. I'm willing to believe that you have lots of cases where those things are outside the ASCII range. Perhaps even most of the cases, depending on where you live. But I do not believe for one second that it never happens.
Re: A popular but wrong way to convert a string to uppercase or lowercase
#163Earlier quoted context omitted.
It’s totally reasonable to assume your users are in the US if your business only sells to people in the US. I work in the health insurance sector; there’s absolutely no chance my company ever sells these products internationally. We can’t even sell them in every state.
It's not reasonable to assume that users in the US have names that only use 7-bit ASCII
It actually is. That covers the vast, vast majority of people in the US.
Re: A popular but wrong way to convert a string to uppercase or lowercase
#164Earlier quoted context omitted.
> That said, 99% time when doing upper- or lowercase operation you're interested just in the 7-bit ASCII range of characters. I think it's more the exact opposite. The only times I'm dealing with 7-bit ASCII is for internal identifiers like variable names or API endpoints. Which is a lot of the time, but I can't ever think of when I've needed my code to change their case. It might literally be never. On the other han…
> Which are never in ASCII because this isn't 1990. This is a very silly statement. I'm willing to believe that you have lots of cases where those things are outside the ASCII range. Perhaps even most of the cases, depending on where you live. But I do not believe for one second that it never happens.
Never stored in ASCII, never limited to ASCII. They're UTF-8, usually.
If somebody's name happens to fit into ASCII that's irrelevant because it's not guaranteed, so you can never blindly do an ASCII case conversion.
For text data meant for users, I literally cannot remember the last time I used a string in ASCII format as opposed to UTF-8 (or UTF-16 in JS). It's certainly over a decade ago.
So yes, when I say never, I literally mean never. Nothing "very silly" about it, sorry.
(Again, excepting identifiers, where case conversion is not generally applicable.)
Re: A popular but wrong way to convert a string to uppercase or lowercase
#165Earlier quoted context omitted.
>Once ppl learn about localization the questions like why a programming language does not do this 'simple text operation' are just a newcomer detector. :) I think you are purposefully misinterpreting the question. They're not asking about converting the case of any Unicode string with locale sensitivity, they're asking about converting the case of ASCII characters. What if your game needs to talk to a server and do s…
> What if your game needs to talk to a server and do some string manipulation in between requests? What conceivable reason would there be to ever need to do that? If the server takes commands in upper case, then have them in upper case from the start. If the server takes commands in lower case, have them in lower case from the start. If the server specifies that you need to invert the case of its response to use in t…
Word censoring? Ease of use? Console commands (i.e. from Quake to minecraft)?
Re: A popular but wrong way to convert a string to uppercase or lowercase
#166Re: A popular but wrong way to convert a string to uppercase or lowercase
#167Earlier quoted context omitted.
> What if your game needs to talk to a server and do some string manipulation in between requests? What conceivable reason would there be to ever need to do that? If the server takes commands in upper case, then have them in upper case from the start. If the server takes commands in lower case, have them in lower case from the start. If the server specifies that you need to invert the case of its response to use in t…
Word censoring? Ease of use? Console commands (i.e. from Quake to minecraft)?
Those sound exactly like the newcomer detectors GP was referring to. What you want is a case-insensitive string comparison, and outside ASCII that's not equivalent to just turning both strings to lowercase and checking equality (or doing a substring search or whatever the task requires)
Re: A popular but wrong way to convert a string to uppercase or lowercase
#168First, you should consider if you even need case folding; for many uses it will be unnecessary, anyways.
Furthermore, the proper way to do case folding will depend on such things as the character set, the language, the specific context of the text being converted (e.g. in some cases specific letters are required, such as abbreviations of the names of SI units), etc. And then, it is not necessarily only "uppercase" and "lowercase", anyways.
There might even be different ways to do by the same language, with possibly disagreements about usage (e.g. the German Eszett did not have an official capital form until 2017, although apparently some type designers did it anyways (and it was in Unicode before then, despite that)).
If the character set is Unicode, then there is not actually the correct way to do it, despite what the Unicode Conspiracy insists otherwise.
Also, for some uses the way that it will need to be done, there will be a specific way that it is required (due to the way that a file format or a protocol or whatever is working), so in such a case if the character set is something other than ASCII then you cannot just assume that it will always work in the same way.
You also cannot necessarily depend on the locale for such a thing, since it might depend on the data, as well.
These things can be as bad as they are, but Unicode just makes these things worse than that. If a program requires a specific case folding and then it will not work because it is the wrong version of Unicode and it is possible to be a security issue and/or other problems.
(Another problem, which applies even if you do not use case folding, is that some people think that all text is or should be Unicode and that one character set is suitable for everything. Actually, one character set cannot be suitable for everything, regardless of what character set it is. Even if it was (which it isn't), it wouldn't be Unicode.)
Re: A popular but wrong way to convert a string to uppercase or lowercase
#169In gamedev there is simple rule: don't try to do any of that. If it is text game needs to show to user then every version of the text that is needed is a translated text. Programmer will never know if context or locale will need word order changes or anything complicated. Just trust the translation team. If text is coming from user - then change design until its not needed to 'convert'. There are major issues just to…
> In gamedev there is simple rule: don't try to do any of that.
I am not in gamedev, but I frequently have to develop middleware that takes in user entered data and formats it in a way that will import into a 3rd party system without errors. And that sometimes means changing the case on strings.
In my experience as a developer, this is very very common requirement.
Luckily I am not forced to use a low level language for any of my work. In C# I can simply do this: "hello world".ToUpper();
Re: A popular but wrong way to convert a string to uppercase or lowercase
#170Earlier quoted context omitted.
In Rust, the APIs are clear if they're ASCII only or unicode aware. https://doc.rust-lang.org/stable/std/primitive.str.html#meth... > ‘Lowercase’ is defined according to the terms of the Unicode Derived Core Property Lowercase. https://doc.rust-lang.org/stable/std/primitive.str.html#meth... > ASCII letters ‘A’ to ‘Z’ are mapped to ‘a’ to ‘z’, but non-ASCII letters are unchanged. Now, "perfectly" is very strong. For e…
> 99% of Unicode stuff Does that include context-dependent conversion rules like o'reilly -> O'Reilly?
that is neither up-casing nor-downcasing, but (de)capitalization, which is a significantly more complex task (which ultimately requires up- or down-casing, but a whole lot more before then).