\d less efficient than [0-9]
I was a bit surprised that Perl does <i>not</i> seem to be matching Unicode digits.  Anyone know why?<p><pre><code>    $ echo '0' | perl -pe 'print "yes: " if m/\d/'
    yes: 0
    $ echo '੧' | perl -pe 'print "yes: " if m/\d/'
    ੧</code></pre>