it should be noted that this can be viewed as a special case of the
witherable packages lovely interfaces
http://hackage.haskell.org/package/witherable-0.3 , which has related
things like
witherM :: Monad
http://hackage.haskell.org/package/base-4.12.0.0/docs/Control-Monad.html#t:M...
m
=> (a -> m (Maybe
http://hackage.haskell.org/package/base-4.12.0.0/docs/GHC-Maybe.html#t:Maybe
b))
-> t a -> m (t b)
On Fri, Feb 8, 2019 at 12:04 PM Carter Schonwald
friend asked me to raise this
previously https://ghc.haskell.org/trac/ghc/ticket/2042 seems like it iddn't happen last time because base lived outside of ghc?
-- | The 'concatMapM' function generalizes 'concatMap' to arbitrary monads. concatMapM :: (Monad m) => (a -> m [b]) -> [a] -> m [b] concatMapM f xs = liftM concat (mapM f xs)