Well,
  1. it was about vowels,
  2. also, many people use split like that, but I find that a simple match (in list context) is better suited. In this case, with reference to your example: 
    my $inverted = join '', map { whatever } $input =~ /./g;

    [download]

In reply to Re^3: Case conversion by blazar
in thread Case conversion by anniyan

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