From c2570f77e64619c90f8a25c6e328c30586077181 Mon Sep 17 00:00:00 2001 From: Stephen Diehl Date: Sat, 20 May 2017 19:03:29 +0100 Subject: [PATCH] better named either helper function, fixes #54 --- src/Either.hs | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/src/Either.hs b/src/Either.hs index 5a18c4f5a..7b5d17f6c 100644 --- a/src/Either.hs +++ b/src/Either.hs @@ -6,6 +6,7 @@ module Either ( , maybeToRight , leftToMaybe , rightToMaybe +, maybeEmpty , maybeToEither ) where @@ -26,5 +27,9 @@ maybeToRight l = maybe (Left l) Right maybeToLeft :: r -> Maybe l -> Either l r maybeToLeft r = maybe (Right r) Left -maybeToEither :: Monoid b => (a -> b) -> Maybe a -> b -maybeToEither = maybe mempty +maybeEmpty :: Monoid b => (a -> b) -> Maybe a -> b +maybeEmpty = maybe mempty + +maybeToEither :: e -> Maybe a -> Either e a +maybeToEither e Nothing = Left e +maybeToEither _ (Just a) = Right a