console functions

docs/Folds.md

@@ -1,2 +1,162 @@
 Folds
 =====
+
+Basic Folds
+-----------
+
+```haskell
+foldMap :: (Foldable t, Monoid m) => (a -> m) -> t a -> m
+```
+
+```haskell
+foldr :: Foldable t => (a -> b -> b) -> b -> t a -> b
+```
+
+```haskell
+foldl :: Foldable t => (b -> a -> b) -> b -> t a -> b
+```
+
+```haskell
+foldr' :: Foldable t => (a -> b -> b) -> b -> t a -> b
+```
+
+```haskell
+foldl' :: Foldable t => (b -> a -> b) -> b -> t a -> b
+```
+
+```haskell
+fold :: Foldable t => Monoid m => t m -> m
+```
+
+```haskell
+toList :: Foldable t => t a -> [a]
+```
+
+```haskell
+null :: Foldable t => t a -> Bool
+```
+
+```haskell
+length :: Foldable t => t a -> Int
+```
+
+```haskell
+elem :: (Eq a, Foldable t) => a -> t a -> Bool
+```
+
+```haskell
+maximum :: (Ord a, Foldable t) => t a -> a
+```
+
+```haskell
+minimum :: (Ord a, Foldable t) => t a -> a
+```
+
+```haskell
+sum :: (Num a, Foldable f) => f a -> a
+```
+
+```haskell
+product :: (Num a, Foldable f) => f a -> a
+```
+
+#### Folding actions
+
+```haskell
+traverse_ :: (Foldable t, Applicative f) => (a -> f b) -> t a -> f ()
+```
+
+```haskell
+for_ :: (Foldable t, Applicative f) => t a -> (a -> f b) -> f ()
+```
+
+*Example*:
+
+```haskell
+>>> for_ [1..4] print
+1
+2
+3
+4
+```
+
+
+#### Applicative Folds
+
+```haskell
+sequenceA_ :: (Foldable t, Applicative f) => t (f a) -> f ()
+```
+
+```haskell
+asum :: (Foldable t, Alternative f) => t (f a) -> f a
+```
+
+#### Monadic Folds
+
+```haskell
+mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()
+```
+
+```haskell
+forM_ :: (Foldable t, Monad m) => t a -> (a -> m b) -> m ()
+```
+
+```haskell
+sequence_ :: (Foldable t, Monad m) => t (m a) -> m ()
+```
+
+```haskell
+msum :: (Foldable t, MonadPlus m) => t (m a) -> m a
+```
+
+```haskell
+foldrM :: (Foldable t, Monad m) => (a -> b -> m b) -> b -> t a -> m b
+```
+
+```haskell
+foldlM :: (Foldable t, Monad m) => (b -> a -> m b) -> b -> t a -> m b
+```
+
+#### Specialized folds
+
+```haskell
+concat :: Foldable t => t [a] -> [a]
+```
+
+```haskell
+concatMap :: Foldable t => (a -> [b]) -> t a -> [b]
+```
+
+```haskell
+and :: Foldable t => t Bool -> Bool
+```
+
+```haskell
+or :: Foldable t => t Bool -> Bool
+```
+
+```haskell
+any :: Foldable t => (a -> Bool) -> t a -> Bool
+```
+
+```haskell
+all :: Foldable t => (a -> Bool) -> t a -> Bool
+```
+
+```haskell
+maximumBy :: Foldable t => (a -> a -> Ordering) -> t a -> a
+```
+
+```haskell
+minimumBy :: Foldable t => (a -> a -> Ordering) -> t a -> a
+```
+
+#### Searches
+
+```haskell
+notElem :: (Foldable t, Eq a) => a -> t a -> Bool
+```
+
+```haskell
+find :: Foldable t => (a -> Bool) -> t a -> Maybe a
+```