23 Jul
2011
23 Jul
'11
10:48 a.m.
Lifting to the List monad gives a very elegant solution: listOutMap :: k -> [a] -> [(k,a)] listOutMap x ys = liftM2 (,) (return x) ys Julian Porter julian.porter@porternet.org http://www.porternet.org On 23 Jul 2011, at 15:08, Christian Maeder wrote:
Am 23.07.2011 03:40, schrieb Dennis Raddle: ...
listOutMap :: Ord k => Map k [a] -> [(k,a)] listOutMap m = concatMap (\(k,a) -> zip (repeat k) a) (M.toList m) ...
instead of "zip" and "repeat" I prefer just "map":
"\ (k, as) -> map (\ a -> (k, a)) as"
(and don't bother to switch on TupleSections for "(k,)")
C.
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