Add monadic variant of iterate

Author: Shimuuar

Data/Vector.hs

@@ -56,7 +56,7 @@ module Data.Vector (
   empty, singleton, replicate, generate, iterateN,
 
   -- ** Monadic initialisation
-  replicateM, generateM, create, createT,
+  replicateM, generateM, iterateNM, create, createT,
 
   -- ** Unfolding
   unfoldr, unfoldrN,
@@ -726,6 +726,11 @@ generateM :: Monad m => Int -> (Int -> m a) -> m (Vector a)
 {-# INLINE generateM #-}
 generateM = G.generateM
 
+-- | /O(n)/ Apply monadic function n times to value. Zeroth element is original value.
+iterateNM :: Monad m => Int -> (a -> m a) -> a -> m (Vector a)
+{-# INLINE iterateNM #-}
+iterateNM = G.iterateNM
+
 -- | Execute the monadic action and freeze the resulting vector.
 --
 -- @

Data/Vector/Generic.hs

@@ -39,7 +39,7 @@ module Data.Vector.Generic (
   empty, singleton, replicate, generate, iterateN,
 
   -- ** Monadic initialisation
-  replicateM, generateM, create, createT,
+  replicateM, generateM, iterateNM, create, createT,
 
   -- ** Unfolding
   unfoldr, unfoldrN,
@@ -711,6 +711,11 @@ generateM :: (Monad m, Vector v a) => Int -> (Int -> m a) -> m (v a)
 {-# INLINE generateM #-}
 generateM n f = unstreamM (MBundle.generateM n f)
 
+-- | /O(n)/ Apply monadic function n times to value. Zeroth element is original value.
+iterateNM :: (Monad m, Vector v a) => Int -> (a -> m a) -> a -> m (v a)
+{-# INLINE iterateNM #-}
+iterateNM n f x = unstreamM (MBundle.iterateNM n f x)
+
 -- | Execute the monadic action and freeze the resulting vector.
 --
 -- @

Data/Vector/Primitive.hs

@@ -42,7 +42,7 @@ module Data.Vector.Primitive (
   empty, singleton, replicate, generate, iterateN,
 
   -- ** Monadic initialisation
-  replicateM, generateM, create, createT,
+  replicateM, generateM, iterateNM, create, createT,
 
   -- ** Unfolding
   unfoldr, unfoldrN,
@@ -609,6 +609,11 @@ generateM :: (Monad m, Prim a) => Int -> (Int -> m a) -> m (Vector a)
 {-# INLINE generateM #-}
 generateM = G.generateM
 
+-- | /O(n)/ Apply monadic function n times to value. Zeroth element is original value.
+iterateNM :: (Monad m, Prim a) => Int -> (a -> m a) -> a -> m (Vector a)
+{-# INLINE iterateNM #-}
+iterateNM = G.iterateNM
+
 -- | Execute the monadic action and freeze the resulting vector.
 --
 -- @

Data/Vector/Storable.hs

@@ -39,7 +39,7 @@ module Data.Vector.Storable (
   empty, singleton, replicate, generate, iterateN,
 
   -- ** Monadic initialisation
-  replicateM, generateM, create, createT,
+  replicateM, generateM, iterateNM, create, createT,
 
   -- ** Unfolding
   unfoldr, unfoldrN,
@@ -619,6 +619,11 @@ generateM :: (Monad m, Storable a) => Int -> (Int -> m a) -> m (Vector a)
 {-# INLINE generateM #-}
 generateM = G.generateM
 
+-- | /O(n)/ Apply monadic function n times to value. Zeroth element is original value.
+iterateNM :: (Monad m, Storable a) => Int -> (a -> m a) -> a -> m (Vector a)
+{-# INLINE iterateNM #-}
+iterateNM = G.iterateNM
+
 -- | Execute the monadic action and freeze the resulting vector.
 --
 -- @

Data/Vector/Unboxed.hs

@@ -62,7 +62,7 @@ module Data.Vector.Unboxed (
   empty, singleton, replicate, generate, iterateN,
 
   -- ** Monadic initialisation
-  replicateM, generateM, create, createT,
+  replicateM, generateM, iterateNM, create, createT,
 
   -- ** Unfolding
   unfoldr, unfoldrN,
@@ -588,6 +588,11 @@ generateM :: (Monad m, Unbox a) => Int -> (Int -> m a) -> m (Vector a)
 {-# INLINE generateM #-}
 generateM = G.generateM
 
+-- | /O(n)/ Apply monadic function n times to value. Zeroth element is original value.
+iterateNM :: (Monad m, Unbox a) => Int -> (a -> m a) -> a -> m (Vector a)
+{-# INLINE iterateNM #-}
+iterateNM = G.iterateNM
+
 -- | Execute the monadic action and freeze the resulting vector.
 --
 -- @