If you want to remove all duplicate letters, not just adjacent ones, this does it without any loops (external to the regex engine).

print $s;
abacadaeafabacadaeafabacadaeafabacadaeafabacadaeafabacadaeaf

$s =~ s[(.)(?=.*?\1)][]g;

print $s;
bcdeaf

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In reply to Re: Remove repeated characters from a string by BrowserUk
in thread Remove repeated characters from a string by Anonymous Monk

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