Dear Monks,

If I have a string in perl, say 'data12.csv', I know I can remove the nun-numbers by using 

#!/usr/bin/perl
my $string=('data12.csv');
$string=~ s/\D//g;
print "$string\n";

[download]

which returns 12. However, when I get a string 'data.csv' the previous lines of code return, not surprisingly, nothing. How can I tell perl to return, in such case, 0?

In reply to How to remove non-numbers from string by kgherman

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