Re: Control.Monad proposal: Add whenJust

10 May 2013


      On Fri, 10 May 2013, Niklas Hambüchen wrote:
...
(Default base case clutter.)
import Data.Foldable
forM_ mUser $ \user -> do
    putStrLn "Mailing!"
    email user
(Not too intuitive/well-named here and "Ambiguous occurrence forM_"
clash with Control.Monad.)
I am against adding a new function to Control.Monad. You should always 
import with explicit identifier lists or with qualification in order to 
allow a larger range of imported library versions and then it makes no 
difference whether you write

   import Control.Monad (forM_)

or

   import Data.Foldable (forM_)

Re: Control.Monad proposal: Add whenJust

Henning Thielemann