From: John Joyce <dangerwillrobinsondanger@...>
Date: 2008-07-10T09:16:46+09:00
Subject: Re: String#upcase/downcase with UTF-8 strings in Ruby 1.9


On Jul 9, 2008, at 6:25 PM, Yukihiro Matsumoto wrote:

> Hi,
>
> In message "Re: String#upcase/downcase with UTF-8 strings in Ruby 1.9"
>    on Thu, 10 Jul 2008 07:09:29 +0900, "Stefan Schmidt" <Stefan.Schmidt@gmx.net 
> > writes:
>
> |in Ruby 1.9 I get the following behaviour:
> |
> |>> "aoueäöüé".upcase
> |=> "AOUEäöüé"
> |>> "AOUEÄÖÜÉ".downcase
> |=> "aoueÄÖÜÉ"
> |
> |I can't find however find a bug in the bug tracking system.
> |Doesn't this qualify as a bug?
>
> The document for String#upcase says:
>
>  call-seq:
>     str.upcase   => new_str
>
>  Returns a copy of <i>str</i> with all lowercase letters replaced  
> with their
>  uppercase counterparts. The operation is locale insensitive---only
>  characters ``a'' to ``z'' are affected.
>  Note: case replacement is effective only in ASCII region.
>
>     "hEllO".upcase   #=> "HELLO"
>
> See "Note:".  Tim Bray have persuaded me to do so, since case
> conversion outside of ASCII region is highly dependent on country,
> language, culture and script.
>
> 							matz.
>
This leaves the perfect opening for people to contribute locale or  
language specific extensions to String.
It would make a great gem with a plug-in architecture.
Just add options for the language you want to use.
In any case it can get very tricky to do character conversions with  
different languages.