diff options
Diffstat (limited to 'compiler/utils')
-rw-r--r-- | compiler/utils/Maybes.lhs | 5 | ||||
-rw-r--r-- | compiler/utils/UniqFM.lhs | 2 | ||||
-rw-r--r-- | compiler/utils/Util.lhs | 10 |
3 files changed, 15 insertions, 2 deletions
diff --git a/compiler/utils/Maybes.lhs b/compiler/utils/Maybes.lhs index 8a612fbb60..859908e266 100644 --- a/compiler/utils/Maybes.lhs +++ b/compiler/utils/Maybes.lhs @@ -14,6 +14,7 @@ module Maybes ( mapCatMaybes, allMaybes, firstJust, firstJusts, + whenIsJust, expectJust, maybeToBool, @@ -68,6 +69,10 @@ mapCatMaybes _ [] = [] mapCatMaybes f (x:xs) = case f x of Just y -> y : mapCatMaybes f xs Nothing -> mapCatMaybes f xs + +whenIsJust :: Monad m => Maybe a -> (a -> m ()) -> m () +whenIsJust (Just x) f = f x +whenIsJust Nothing _ = return () \end{code} \begin{code} diff --git a/compiler/utils/UniqFM.lhs b/compiler/utils/UniqFM.lhs index 680300abd4..862af99443 100644 --- a/compiler/utils/UniqFM.lhs +++ b/compiler/utils/UniqFM.lhs @@ -20,7 +20,7 @@ and ``addToUFM\_C'' and ``Data.IntMap.insertWith'' differ in the order of arguments of combining function. \begin{code} -{-# LANGUAGE GeneralizedNewtypeDeriving #-} +{-# LANGUAGE DeriveTraversable, GeneralizedNewtypeDeriving #-} {-# OPTIONS -Wall #-} module UniqFM ( diff --git a/compiler/utils/Util.lhs b/compiler/utils/Util.lhs index 6d42ce7dfe..dd947ffd93 100644 --- a/compiler/utils/Util.lhs +++ b/compiler/utils/Util.lhs @@ -14,7 +14,7 @@ module Util ( -- * General list processing zipEqual, zipWithEqual, zipWith3Equal, zipWith4Equal, - zipLazy, stretchZipWith, + zipLazy, stretchZipWith, zipWithAndUnzip, unzipWith, @@ -351,6 +351,14 @@ mapAndUnzip3 f (x:xs) in (r1:rs1, r2:rs2, r3:rs3) +zipWithAndUnzip :: (a -> b -> (c,d)) -> [a] -> [b] -> ([c],[d]) +zipWithAndUnzip f (a:as) (b:bs) + = let (r1, r2) = f a b + (rs1, rs2) = zipWithAndUnzip f as bs + in + (r1:rs1, r2:rs2) +zipWithAndUnzip _ _ _ = ([],[]) + mapAccumL2 :: (s1 -> s2 -> a -> (s1, s2, b)) -> s1 -> s2 -> [a] -> (s1, s2, [b]) mapAccumL2 f s1 s2 xs = (s1', s2', ys) where ((s1', s2'), ys) = mapAccumL (\(s1, s2) x -> case f s1 s2 x of |