Hi Mark, What's the definition of foldr in terms of map? As far as I was aware, its not possible.
And as it happens, map is (or is sometimes) defined in term of foldr :-) While you can use mutual recursion, you can't define a in terms of b and b in terms of a unless one of them actually does something at the end - so it does depend exactly what the definitions are. Thanks Neil 2009/3/16 Mark Spezzano <mark.spezz...@chariot.net.au>: > Hi, > > > > I’ve noticed that it’s possible to define map as foldr and foldr as a map. > Would this be sensible to define both in terms of each other in the Prelude? > i.e mutually recursive? > > > > Cheers, > > > > Mark > > > > No virus found in this outgoing message. > Checked by AVG. > Version: 7.5.557 / Virus Database: 270.11.15/2003 - Release Date: 15/03/2009 > 2:07 PM > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe > > _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
