Re: [Haskell-beginners] Map on Nested Lists

2010/4/8 Ben Derrett :

Hi, I'm trying to write a generalization of the map function that operates on nested lists, e.g. [[a]] or [[[a]]]. (It should map all elements of type a (not list) with f) I was thinking of something along these lines: mapN f *list of type [a] (where a is not a list type)* = map f l mapN f l = (mapN f (head l)):(mapN f (tail l))

Any suggestions about how to go about this? Many thanks, Ben

I think you should look into generic programming for doing this, e.g. "Scrap Your Boilerplate". There are (at least) three papers on it[1]. [1]: http://research.microsoft.com/en-us/um/people/simonpj/Papers/hmap/index.htm -- Deniz Dogan