# Alternative f => [f a] -> f a -fgl -quickcheck

The sum of a collection of actions, generalizing concat.
This generalizes the list-based concat function.
The union of a list of maps. > unions [(fromList [(5, "a"), (3, "b")]), (fromList [(5, "A"), (7, "C")]), (fromList [(5, "A3"), (3, "B3")])] > == fromList [(3, "b"), (5, "a"), (7, "C")] > unions [(fromList [(5, "A3"), (3, "B3")]), (fromList [(5, "A"), (7, "C")]), (fromList [(5, "a"), (3, "b")])] > == fromList [(3, "B3"), (5, "A3"), (7, "C")]
Combines all parsers in the specified list.
Combines all parsers in the specified list.
Concatenate a list of lists.
The sum of a collection of actions, generalizing concat.
The union of a list of maps, with a combining operation. > unionsWith (++) [(fromList [(5, "a"), (3, "b")]), (fromList [(5, "A"), (7, "C")]), (fromList [(5, "A3"), (3, "B3")])] > == fromList [(3, "bB3"), (5, "aAA3"), (7, "C")]
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.
Evaluate each action in the sequence from left to right, and ignore the results.
The union of a list of sets: (unions == foldl union empty).
The transpose function transposes the rows and columns of its argument. For example, > transpose [[1,2,3],[4,5,6]] == [[1,4],[2,5],[3,6]]
The concatenation of all the elements of a container of lists.
One or none.
Note: this function is deprecated, please use mask instead. Applying block to a computation will execute that computation with asynchronous exceptions blocked. That is, any thread which attempts to raise an exception in the current thread with Control.Exception.throwTo will be blocked until asynchronous exceptions are unblocked again. There's no need to worry about re-enabling asynchronous exceptions; that is done automatically on exiting the scope of block. Threads created by Control.Concurrent.forkIO inherit the blocked state from the parent; that is, to start a thread in blocked mode, use block \$ forkIO .... This is particularly useful if you need to establish an exception handler in the forked thread before any asynchronous exceptions are received.