Add intercalate and split to Data.List

diff --git a/Data/List.hs b/Data/List.hs
index f9a1226..7c3cede 100644 (file)
--- a/Data/List.hs
+++ b/Data/List.hs
@@ -35,7 +35,6 @@ module Data.List
    , reverse           -- :: [a] -> [a]
 
    , intersperse       -- :: a -> [a] -> [a]
-   , intercalate       -- :: [a] -> [[a]] -> [a]
    , transpose         -- :: [[a]] -> [[a]]
 
    -- * Reducing lists (folds)
@@ -93,8 +92,6 @@ module Data.List
    , span              -- :: (a -> Bool) -> [a] -> ([a], [a])
    , break             -- :: (a -> Bool) -> [a] -> ([a], [a])
 
-   , split             -- :: Eq a => a -> [a] -> [[a]]
-
    , group             -- :: Eq a => [a] -> [[a]]
 
    , inits             -- :: [a] -> [[a]]
@@ -399,12 +396,6 @@ intersperse _   []      = []
 intersperse _   [x]     = [x]
 intersperse sep (x:xs)  = x : sep : intersperse sep xs
 
--- | 'intercalate' @xs xss@ is equivalent to @('concat' ('intersperse' xs xss))@.
--- It inserts the list @xs@ in between the lists in @xss@ and concatenates the
--- result.
-intercalate :: [a] -> [[a]] -> [a]
-intercalate xs xss = concat (intersperse xs xss)
-
 -- | The 'transpose' function transposes the rows and columns of its argument.
 -- For example,
 --
@@ -677,19 +668,6 @@ unzip7             =  foldr (\(a,b,c,d,e,f,g) ~(as,bs,cs,ds,es,fs,gs) ->
 deleteFirstsBy          :: (a -> a -> Bool) -> [a] -> [a] -> [a]
 deleteFirstsBy eq       =  foldl (flip (deleteBy eq))
 
--- | 'split' @x xs@ divides the list @xs@ at every occurrence of @x@ and
--- removes those occurrences.
---
--- Example:
---
--- > split 'i' "mississippi" -> ["m","ss","ss","pp",""]
--- > split 'i' [] -> [""]
-split :: Eq a => a -> [a] -> [[a]]
-split x xs = let (f,r) = break (==x) xs
-             in f : case r of
-                      [] -> []
-                      (_:ys) -> split x ys
-
 -- | The 'group' function takes a list and returns a list of lists such
 -- that the concatenation of the result is equal to the argument.  Moreover,
 -- each sublist in the result contains only equal elements.  For example,