for function for #19

src/Protolude.hs

@@ -17,6 +17,7 @@ module Protolude (
   print,
   throwIO,
   throwTo,
+  foreach,
   show,
 
   LText,
@@ -393,6 +394,9 @@ throwIO = liftIO . Control.Exception.throwIO
 throwTo :: (X.MonadIO m, Exception e) => ThreadId -> e -> m ()
 throwTo tid e = liftIO (Control.Exception.throwTo tid e)
 
+foreach :: Functor f => f a -> (a -> b) -> f b
+foreach = flip fmap
+
 show :: (Show a, StringConv String b) => a -> b
 show x = toS (PBase.show x)
 {-# SPECIALIZE show :: Show  a => a -> Text  #-}