From e9a53b69ad68e531a789eff3128f7304fd411808 Mon Sep 17 00:00:00 2001 From: Ben Sima Date: Wed, 15 Apr 2020 15:24:32 -0700 Subject: Lint fixes, also delete Biz.Language --- System/Random/Shuffle.hs | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) (limited to 'System') diff --git a/System/Random/Shuffle.hs b/System/Random/Shuffle.hs index 774e7b4..d3cd387 100644 --- a/System/Random/Shuffle.hs +++ b/System/Random/Shuffle.hs @@ -25,8 +25,7 @@ module System.Random.Shuffle where import Control.Monad - ( liftM, - liftM2, + ( liftM2, ) import Control.Monad.Random ( MonadRandom, @@ -49,13 +48,13 @@ data Tree a -- | Convert a sequence (e1...en) to a complete binary tree buildTree :: [a] -> Tree a -buildTree = (fix growLevel) . (map Leaf) +buildTree = fix growLevel . map Leaf where growLevel _ [node] = node growLevel self l = self $ inner l inner [] = [] inner [e] = [e] - inner (e1 : e2 : es) = e1 `seq` e2 `seq` (join e1 e2) : inner es + inner (e1 : e2 : es) = e1 `seq` e2 `seq` join e1 e2 : inner es join l@(Leaf _) r@(Leaf _) = Node 2 l r join l@(Node ct _ _) r@(Leaf _) = Node (ct + 1) l r join l@(Leaf _) r@(Node ct _ _) = Node (ct + 1) l r @@ -70,7 +69,7 @@ shuffle elements = shuffleTree (buildTree elements) where shuffleTree (Leaf e) [] = [e] shuffleTree tree (r : rs) = - let (b, rest) = extractTree r tree in b : (shuffleTree rest rs) + let (b, rest) = extractTree r tree in b : shuffleTree rest rs shuffleTree _ _ = error "[shuffle] called with lists of different lengths" -- Extracts the n-th element from the tree and returns -- that element, paired with a tree with the element @@ -99,7 +98,7 @@ shuffle' elements len = shuffle elements . rseq len -- independent sample from a uniform random distribution -- [0..n-i] rseq :: RandomGen gen => Int -> gen -> [Int] - rseq n = fst . unzip . rseq' (n - 1) + rseq n = map fst . rseq' (n - 1) where rseq' :: RandomGen gen => Int -> gen -> [(Int, gen)] rseq' 0 _ = [] @@ -111,7 +110,7 @@ shuffle' elements len = shuffle elements . rseq len shuffleM :: (MonadRandom m) => [a] -> m [a] shuffleM elements | null elements = return [] - | otherwise = liftM (shuffle elements) (rseqM (length elements - 1)) + | otherwise = shuffle elements <$> rseqM (length elements - 1) where rseqM :: (MonadRandom m) => Int -> m [Int] rseqM 0 = return [] -- cgit v1.2.3