UPDATE: Sound enough code (and can be adapted (below) to OP's needs), but NOT a complete answer to OP's question, which I mis-read.

Use the inverse of your regex, namely:

$string=~ s/\d//g;

like this without having to add additional tests to deal with strings which have no numbers:

C:\>perl -E "my $string=('data12.csv');$string=~ s/\d//g;say $string;
data.csv

C:\>perl -E "my $string=('data.csv');$string=~ s/\d//g;say $string;"
data.csv

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Spirit of the Monastery

In reply to Re: How to remove non-numbers from string by ww
in thread How to remove non-numbers from string by kgherman

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