Re: [Haskell-cafe] Combine list of sorted lists

Sorry to Neil for multiple copies. On 29/12/06, Neil Mitchell wrote:

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I am not sure how to express f1 with map? how do I say (lambda (ls) (map (lambda (x) (list x)) ls)) in Haskell? map ([]) ?

map (:[]), :[] takes a single element and puts it into a list. Some people refer to this as "box"

You can pretty much directly translate your Lisp: \ls -> map (\x -> [x]) ls Which eta-reduces to: map (\x -> [x]) Now the inner lambda can be written as: \x -> x : [] Or, (: []) That's a section on the ':' operator. So the whole thing becomes: map (:[]) Hope that helps. -- -David House, dmhouse@gmail.com