rwmj on \d less efficient than [0-9]

I was a bit surprised that Perl does not seem to be matching Unicode digits. Anyone know why?

    $ echo '0' | perl -pe 'print "yes: " if m/\d/'
    yes: 0
    $ echo '੧' | perl -pe 'print "yes: " if m/\d/'
    ੧

You have to tell perl to expect utf8 from stdin (switch -C).

  $ echo '੧' | perl -C -pe 'print "yes: " if m/\d/'
  and
  $ perl -e 'use utf8; print "yes\n" if "੧" =~ m/\d/;'

both work :)

`man perlunicode` is chockfull of utf8-related stuff (and it's looong): http://perldoc.perl.org/5.14.0/perlunicode.html

Ditto PHP:

  php > var_export(preg_match("/\d/", "1"));
  1
  php > var_export(preg_match("/\d/", "۳"));
  0

Add /u

    php > var_export(preg_match("/\d/u", "۳"));

Try:

    utf8::upgrade($string)

And/or:

    use feature 'unicode_strings'

The documentation says \d should match if you use /u on the regex

Comments