If speed is your need, then compare this: 

sub buk_s {
    my @c;
    $c[ $_ ] = $_ for unpack 'C*', $_[ 0 ];
    pack 'C*', grep defined, @c;
}

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re^3: Collapsing a string to unique characters by BrowserUk
in thread Collapsing a string to unique characters by dwhite20899

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