There is that formulation, though usually I find I need to do it with an alternative instead:
altconcat alt [] = alt altconcat _ (a:as) = go a as where go acc [] = acc go acc (b:bs) = go (acc <> b) bs Both are "kind of, sort of" bringing you up to a Monoid though... On 3 May 2011 12:56, Holger Siegel <holgersiege...@yahoo.de> wrote: > You have to provide the "neutral" element by yourself: _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe