X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=Data%2FSet.hs;h=f321abf31fe07f55f16c11d3ed0d74d6437dc22d;hb=0a41af38169035a4359c0c29bc1219af564dce64;hp=b357f96d852b9c8930e91123e21c3d433f4eebdb;hpb=0d6c1599c246100deb2fa54315811ed94d1a300c;p=ghc-base.git diff --git a/Data/Set.hs b/Data/Set.hs index b357f96..f321abf 100644 --- a/Data/Set.hs +++ b/Data/Set.hs @@ -111,8 +111,7 @@ module Data.Set ( delFromSet, -- :: Ord a => Set a -> a -> Set a ) where -import Prelude hiding (filter,foldr,foldl,null,map) -import Data.Monoid +import Prelude hiding (filter,foldr,null,map) import qualified Data.List as List import Data.Typeable @@ -146,12 +145,12 @@ data Set a = Tip type Size = Int +#if __GLASGOW_HASKELL__ + {-------------------------------------------------------------------- A Data instance --------------------------------------------------------------------} -#if __GLASGOW_HASKELL__ - -- This instance preserves data abstraction at the cost of inefficiency. -- We omit reflection services for the sake of data abstraction. @@ -240,7 +239,7 @@ isProperSubsetOf s1 s2 -- | /O(n+m)/. Is this a subset? --- @(s1 `isSubsetOf` s2)@ tells whether s1 is a subset of s2. +-- @(s1 `isSubsetOf` s2)@ tells whether @s1@ is a subset of @s2@. isSubsetOf :: Ord a => Set a -> Set a -> Bool isSubsetOf t1 t2 = (size t1 <= size t2) && (isSubsetOfX t1 t2) @@ -250,7 +249,7 @@ isSubsetOfX t Tip = False isSubsetOfX (Bin _ x l r) t = found && isSubsetOfX l lt && isSubsetOfX r gt where - (found,lt,gt) = splitMember x t + (lt,found,gt) = splitMember x t {-------------------------------------------------------------------- @@ -284,7 +283,7 @@ deleteMax Tip = Tip {-------------------------------------------------------------------- Union. --------------------------------------------------------------------} --- | The union of a list of sets: (@unions == foldl union empty@). +-- | The union of a list of sets: (@'unions' == 'foldl' 'union' 'empty'@). unions :: Ord a => [Set a] -> Set a unions ts = foldlStrict union empty ts @@ -347,7 +346,7 @@ intersect' t (Bin _ x l r) | found = join x tl tr | otherwise = merge tl tr where - (found,lt,gt) = splitMember x t + (lt,found,gt) = splitMember x t tl = intersect' lt l tr = intersect' gt r @@ -379,7 +378,7 @@ partition p (Bin _ x l r) ----------------------------------------------------------------------} -- | /O(n*log n)/. --- @map f s@ is the set obtained by applying @f@ to each element of @s@. +-- @'map' f s@ is the set obtained by applying @f@ to each element of @s@. -- -- It's worth noting that the size of the result may be smaller if, -- for some @(x,y)@, @x \/= y && f x == f y@ @@ -389,7 +388,7 @@ map f = fromList . List.map f . toList -- | /O(n)/. The -- --- @mapMonotonic f s == 'map' f s@, but works only when @f@ is monotonic. +-- @'mapMonotonic' f s == 'map' f s@, but works only when @f@ is monotonic. -- /The precondition is not checked./ -- Semi-formally, we have: -- @@ -427,7 +426,7 @@ elems s {-------------------------------------------------------------------- Lists --------------------------------------------------------------------} --- | /O(n)/. Convert the set to an ascending list of elements. +-- | /O(n)/. Convert the set to a list of elements. toList :: Set a -> [a] toList s = toAscList s @@ -506,15 +505,6 @@ instance Ord a => Ord (Set a) where compare s1 s2 = compare (toAscList s1) (toAscList s2) {-------------------------------------------------------------------- - Monoid ---------------------------------------------------------------------} - -instance Ord a => Monoid (Set a) where - mempty = empty - mappend = union - mconcat = unions - -{-------------------------------------------------------------------- Show --------------------------------------------------------------------} instance Show a => Show (Set a) where @@ -603,7 +593,7 @@ filterLt cmp (Bin sx x l r) {-------------------------------------------------------------------- Split --------------------------------------------------------------------} --- | /O(log n)/. The expression (@split x set@) is a pair @(set1,set2)@ +-- | /O(log n)/. The expression (@'split' x set@) is a pair @(set1,set2)@ -- where all elements in @set1@ are lower than @x@ and all elements in -- @set2@ larger than @x@. @x@ is not found in neither @set1@ nor @set2@. split :: Ord a => a -> Set a -> (Set a,Set a) @@ -616,13 +606,13 @@ split x (Bin sy y l r) -- | /O(log n)/. Performs a 'split' but also returns whether the pivot -- element was found in the original set. -splitMember :: Ord a => a -> Set a -> (Bool,Set a,Set a) -splitMember x Tip = (False,Tip,Tip) +splitMember :: Ord a => a -> Set a -> (Set a,Bool,Set a) +splitMember x Tip = (Tip,False,Tip) splitMember x (Bin sy y l r) = case compare x y of - LT -> let (found,lt,gt) = splitMember x l in (found,lt,join y gt r) - GT -> let (found,lt,gt) = splitMember x r in (found,join y l lt,gt) - EQ -> (True,l,r) + LT -> let (lt,found,gt) = splitMember x l in (lt,found,join y gt r) + GT -> let (lt,found,gt) = splitMember x r in (join y l lt,found,gt) + EQ -> (l,True,r) {-------------------------------------------------------------------- Utility functions that maintain the balance properties of the tree. @@ -831,7 +821,7 @@ showTree s {- | /O(n)/. The expression (@showTreeWith hang wide map@) shows the tree that implements the set. If @hang@ is @True@, a /hanging/ tree is shown otherwise a rotated tree is shown. If - @wide@ is true, an extra wide version is shown. + @wide@ is 'True', an extra wide version is shown. > Set> putStrLn $ showTreeWith True False $ fromDistinctAscList [1..5] > 4