Just forgot to mention that the pickaxe book, for "\s", says "For 
Unicode, add Line_Separator codepoints.".

This is wrong because even LINE SEPARATOR itself, \u2028, doesn't match 
\s. It would also be wrong in that the result would be to match ASCII 
whitespace and Unicode line separators, whereas other Unicode whitespace 
would be ignored.

Regards,   Martin.

On 2012/10/15 8:51, "Martin J. Drst" wrote:
> My understanding is that in Ruby, all the pre-Unicode escapes, and in
> particular "\s", still refer only to characters in the ASCII range.
>
> My understanding is that this was done in this way for backwards
> compatibility, and on purpose. This can be explained as follows: Maybe
> somebody wrote a script doing some processing where they wanted to match
> ASCII 'space' characters. They used \s. If Ruby would change \s to
> suddenly match way more than before, the meaning of that program would
> change. Maybe it would change just in the right way. But maybe it would
> change in an unintended way.
>
> So the decision was to not second-guess the programmer. As a result,
> this does not behave the same way as what's suggested in Unicode TR #18.
> But please note that UTR #18 doesn't *require* \s to be treated as
> Unicode whitespace, it just *recommends* to do so (see
> http://www.unicode.org/reports/tr18/#Compatibility_Properties).
>
> If you want to match against Unicode whitespace, what you should do is
> the following:
>
> "\u00a0" =~ /\p{Whitespace}/u
>
> Regards, Martin.
>
> On 2012/10/14 8:37, t0d0r (Todor Dragnev) wrote:
>>
>> Issue #7154 has been reported by t0d0r (Todor Dragnev).
>>
>> ----------------------------------------
>> Bug #7154: For whatever reason \s doesn't match \u00a0.
>> https://bugs.ruby-lang.org/issues/7154
>>
>> Author: t0d0r (Todor Dragnev)
>> Status: Open
>> Priority: Normal
>> Assignee:
>> Category: core
>> Target version:
>> ruby -v: 1.9.3p286
>>
>>
>> The problem is already explained here:
>>
>> http://stackoverflow.com/questions/2588942/convert-non-breaking-spaces-to-spaces-in-ruby
>>
>>
>> I just hit it today.
>>
>>
>
>