diff options
Diffstat (limited to 'compiler/utils')
| -rw-r--r-- | compiler/utils/Util.lhs | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/compiler/utils/Util.lhs b/compiler/utils/Util.lhs index 12249d3a2b..d87f526bc8 100644 --- a/compiler/utils/Util.lhs +++ b/compiler/utils/Util.lhs @@ -19,7 +19,7 @@ module Util ( unzipWith, mapFst, mapSnd, - mapAndUnzip, mapAndUnzip3, + mapAndUnzip, mapAndUnzip3, mapAccumL2, nOfThem, filterOut, partitionWith, splitEithers, foldl1', foldl2, count, all2, @@ -35,6 +35,7 @@ module Util ( -- * Tuples fstOf3, sndOf3, thirdOf3, firstM, first3M, + third3, uncurry3, -- * List operations controlled by another list @@ -224,6 +225,9 @@ fstOf3 (a,_,_) = a sndOf3 (_,b,_) = b thirdOf3 (_,_,c) = c +third3 :: (c -> d) -> (a, b, c) -> (a, b, d) +third3 f (a, b, c) = (a, b, f c) + uncurry3 :: (a -> b -> c -> d) -> (a, b, c) -> d uncurry3 f (a, b, c) = f a b c \end{code} @@ -353,6 +357,12 @@ mapAndUnzip3 f (x:xs) (rs1, rs2, rs3) = mapAndUnzip3 f xs in (r1:rs1, r2:rs2, r3:rs3) + +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 + (s1', s2', y) -> ((s1', s2'), y)) + (s1, s2) xs \end{code} \begin{code} |