I have the same question but how is this done if there are for example EVO:001, EV0:002, EVO:003 in a file and I want each one incremented.. I just want to supply EVO: then have it increment the number part. The closest I have gotten is this but it injects a one instead of incrementing the variable

#!perl=C:\bin\perl
use warnings;
use strict;

use Tie::File;

tie my @data, 'Tie::File', 'myfile.txt' or die $!;
sub inc { 
    my ($num) = @_; ++$num 
} 
s/(MyString\d+)/$1 . (inc($2))/eg for @data;

untie @data;
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