I think you'll find that that runs much faster than one regexp involving alternation....

Well, I don't really care much about faster runtimes -- most of what I do waits on disk access and network I/O long before it runs into RAM or CPU limits, so which regex is fastest almost never comes into play.

I try to write primarily for readability. I realize, of course, that "readability" is subjective. But, I find s{^\s+|\s+$}{}g to be more readable than the two-line alternative. When I see that one line, I immediately think "ok, trim whitespace from the ends". When I see the two, I have to stop and think about it. Just me.

One of the things I like about Python¹ is the readability of performing this action:

text = " a string of some sort, with space at either end   "
text = text.strip()
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I think that's what draws me to Text::Trim (if I have to do the step repeatedly, especially):

my $text = " a string of some sort, with space at either end   ";
$text = trim( $text );
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Of course, creating a dependency for something like that seems a little excessive, so I've recently taken to

my $TRIM_WHITESPACE_RE = qr/^\s+|\s+$/
## ... later on .. ##
$text =~ s/$TRIME_WHITESPACE_RE//g;
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1: I know, I know. :) Seriously, though, Python has some nifty things in it, even if I still like Perl better.