While nowhere close to a winner, this beats all the other regex solutions: 
sub lookahead
{
    my ($sentence, $wantedLetters) = @_;
    $wantedLetters =~ s/(.)/(?=.*?\Q$1\E)/sg;
    $sentence =~ /^$wantedLetters/s;
}

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In reply to Re: Benchmarking "Are all these characters in this sentence?" by ysth
in thread Benchmarking "Are all these characters in this sentence?" by RMGir

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