I am trying to increment a string matching /[A-Z][A-Z0-9]+/ but cannot use the ++ operator, since the last character could be A-Z. My needs are to make sure I haven't seen this string before, and keep the first character the same. Is there a way to convert to a number, increment, and convert back to a string?

Here is what I have so far, that I know doesn't work:

  +101        $used{"FOO123Z"} = 1;
..snip..
  +323        my $new="FOO123Z";
  +324        my $len = length($new);
  +325        while ( defined $used{$new} && $len > 0 ){  ## Keep the 
+first character the same
  +326          foreach my $c (("A" .. "Z"), 0..9){
  +327            $new =~ s/(.{$len}).(.*)/${1}${c}${2}/ if defined $u
+sed{$new};
  +328          }
  +329          $len-- if defined $used{$new} ;
  +330        }
  +331        $used{$new} = 1;

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In reply to Increment a mixed alphanumeric by miketosh

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