You know, we're getting pretty close to the terseness of Haskell, but (I think) it's still rather readable:

my $compress = sub ($x) {
    state $previous;
    $x ne $previous ?? $previous = $x !! return;
}

[download]

And in Haskell:

compress :: Eq a => [a] -> [a]
compress = map head . group

[download]

Update: as concise, but less "golfy":

my $compress = sub ($x) {
    state $previous;
    return $x ne $previous ?? $previous = $x !! ();
}

[download]

Cheers,
Ovid

New address of my CGI Course.

In reply to Re^3: 99 Problems in Perl6 by Ovid
in thread 99 Problems in Perl6 by Ovid

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