my $number = 123;
$number =~ s/(\d)(?=(\d{3})+(\D|$))/$1\,/g;
print $number;
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I get no output from the print, almost as if $number if undef. If I use 1234 as the input, I get 1,234 out - which is right ..

That's with Perl 5.004.04 on Solaris .. maybe it's a version thing.

-- Foxcub

If it doesn't print anything, it's a Solaris issue, not a version thing. But I find that highly unlikely. I ran the above code on all released versions of Perl since 5.000, and it prints '123' on all of them, except for the versions 5.004_68 up till 5.005_02, where it prints '1,2,3'.

Abigail