A popular but wrong way to convert a string to uppercase or lowercase
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A popular but wrong way to convert a string to uppercase or lowercase
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Re: A popular but wrong way to convert a string to uppercase or lowercase
#2As 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.
Re: A popular but wrong way to convert a string to uppercase or lowercase
#3It is issues like this due to which I gave up on C++. There are so many ways to do something and every way is freaking wrong!
An acceptable solution is given at the end of the article:
> If you use the International Components for Unicode (ICU) library, you can use u_strToUpper and u_strToLower.
Makes you wonder why this isn't part of the C++ standard library itself. Every revision of the C++ standard brings with itself more syntax and more complexity in the language. But as a user of C++ I don't need more syntax and more complexity in the language. But I do need more standard library functions that solves these ordinary real-world programming problems.
Re: A popular but wrong way to convert a string to uppercase or lowercase
#4As 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.
No, when you are doing string manipulation, you are almost never interestet in just the seven bit ASCII range, as there is almost no language that can be written using just that.
Re: A popular but wrong way to convert a string to uppercase or lowercase
#5The key takeaway here is that you can't correctly process a string if you don't what language it's in. That includes variants of the same language with different rules, eg en-US and en-UK or es-MX and es-ES.
If you are handling multilingual text the locale is mandatory metadata.
Re: A popular but wrong way to convert a string to uppercase or lowercase
#6As 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.
No, when you are doing string manipulation, you are almost never interestet in just the seven bit ASCII range, as there is almost no language that can be written using just that.
I would argue that for most programs when you're doing string manipulation you're doing it for internal programming reasons - logs, error messages, etc. In that case you are in nearly full control of the strings and therefore can declare that you're only working with ASCII.
The other normal cases of string usage are file paths and user interface, and the needed operations can be done with simple string functions, and even in UTF8 encoding the characters you care about are in the ASCII range. With file paths the manipulations that you're most often doing is path based so you only care about '/', '\', ':', and '.' ASCII characters. With user interface elements you're likely to be using them as just static data and only substituting values into placeholders when necessary.
Re: A popular but wrong way to convert a string to uppercase or lowercase
#7As 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.
No, when you are doing string manipulation, you are almost never interestet in just the seven bit ASCII range, as there is almost no language that can be written using just that.
> as there is almost no language that can be written using just that.
99% of use cases I've seen have nothing to do with human language.
1% human language case that is needs to be handled properly using a proper Unicode library.
Your mileage (percentages) may vary depending on your job.
Re: A popular but wrong way to convert a string to uppercase or lowercase
#8...and that is why you use QString if you are using the Qt framework. QString is a string class that actually does what you want when used in the obvious way. It probably helps that it was mostly created by people with "ASCII+" native languages. Or with customers that expect not exceedingly dumb behavior. The methods are called QString::toUpper() and QString::toLower() and take only the implicit "this" argument, unlike Win32 LCMapStringEx() which takes 5-8 arguments...
Re: A popular but wrong way to convert a string to uppercase or lowercase
#9It is issues like this due to which I gave up on C++. There are so many ways to do something and every way is freaking wrong! An acceptable solution is given at the end of the article: > If you use the International Components for Unicode (ICU) library, you can use u_strToUpper and u_strToLower. Makes you wonder why this isn't part of the C++ standard library itself. Every revision of the C++ standard brings with its…
>It is issues like this due to which I gave up on C++. There are so many ways to do something and every way is freaking wrong!
These are mostly unicode or linguistics problems.
Re: A popular but wrong way to convert a string to uppercase or lowercase
#10It is issues like this due to which I gave up on C++. There are so many ways to do something and every way is freaking wrong! An acceptable solution is given at the end of the article: > If you use the International Components for Unicode (ICU) library, you can use u_strToUpper and u_strToLower. Makes you wonder why this isn't part of the C++ standard library itself. Every revision of the C++ standard brings with its…
> There are so many ways to do something and every way is freaking wrong!
That's life! The perfect way does not exist. The best you can do is be aware of the tradeoffs, and languages like C++ absolutely throw them in your face at every single opportunity. It's fatiguing, and writing in javascript or python allows us to uphold the facade that everything is okay and that we don't have to worry about a thing.