...because of a bug, but that applies to both [^\S \n] and \s(?<![ \n]).

What surprises me is that the bug doesn't seem to apply to both (with my perl), i.e. it only shows up with the negated char class — from which it would follow that \S and \s aren't complementary...

However, as the issue appears to be fixed in 5.14, I think we can leave it at that.

 

(Update) But what about the vertical tab U+000B ? 

$ /usr/local/bin/perl5.14.1 -E'say "\x0b" =~ /\s/ ?1:0;'
0
$ /usr/local/bin/perl5.14.1 -E'say "\N{U+000B}" =~ /\s/ ?1:0;'
0

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Shouldn't it be considered white space?  (Not that I've ever encountered it in the wild... just curious.)

In reply to Re^4: regexp: removing extra whitespace by Eliya
in thread regexp: removing extra whitespace by perlmax

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