The "alternative solution" posted there doesn't suffer from the monomorphism restriction*, and thus does less to propagate the myth that one has to be a genius to write code in Haskell. It also works correctly with empty input :-) 

compress []       = []
compress [a]      = [a]           -- singleton list
compress (x:y:xs) = (if x == y then [] else [x]) ++ compress (y:xs)

[download]
*Something that, for the casual programmer, is quite technical but uninteresting, has a scary name, and a not-that-friendly error message.

In reply to Re^6: 99 Problems in Perl6 by gaal
in thread 99 Problems in Perl6 by Ovid

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