-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Wait-free Tree Counter
--   
--   A wait-free tree counter. Creates a binary tree of counters, with each
--   leaf associated with a thread. Leaves can be split, creating a new
--   leaf for the current thread and another that can be used by another
--   thread. Each thread will act on different leaves, meaning the actions
--   are wait-free. A read is performed on the counter by recursively
--   traversing it and summing the value of the counters in the nodes and
--   leaves of the tree. (UPDATE: removed useless dependency)
@package TreeCounter
@version 0.0.2


-- | A wait-free tree counter. Creates a binary tree of counters, with each
--   leaf associated with a thread. Leaves can be split, creating a new
--   leaf for the current thread and another that can be used by another
--   thread. Each thread will act on different leaves, meaning the actions
--   are wait-free. A read is performed on the counter by recursively
--   traversing it and summing the value of the counters in the nodes and
--   leaves of the tree.
module Data.NonBlocking.WaitFree.TreeCounter

-- | A wait-free concurrent Tree Counter, a binary tree of counters, with
--   each leaf associated with a thread. Leaves can be split, creating a
--   new leaf for the current thread and another that can be used by
--   another thread. Increments are wait-free as long as each thread
--   performs them on different instance of TreeCounter split from an
--   initial instance using <a>splitTreeCounter</a>, prone to ABA problem
--   otherwise.
data TreeCounter r

-- | TreeCounter inside the IO Monad.
type TreeCounterIO = TreeCounter IORef

-- | TreeCounter inside the STM Monad.
type TreeCounterSTM = TreeCounter TVar

-- | Creates a new instance of the <a>TreeCounter</a> data type,
--   instanciated to the value of the input, with type in the
--   <a>Integral</a> class.
newTreeCounter :: (MonadAtomicRef r m, Integral a) => a -> m (TreeCounter r)

-- | Splits a <a>TreeCounter</a> instance, updating it to a new leaf and
--   creating a new one, allowing another thread to increment the counter
--   in a wait-free manner.
splitTreeCounter :: MonadAtomicRef r m => TreeCounter r -> m (TreeCounter r)

-- | Increments the <a>TreeCounter</a> in an atomic manner as long as this
--   thread is the only thread incrementing the counter from this instance
--   <a>TreeCounter</a>
incTreeCounter :: MonadAtomicRef r m => TreeCounter r -> m ()

-- | Reads the total value of the binary tree of counters associated with
--   this instance of <a>TreeCounter</a>.
readTreeCounter :: (MonadAtomicRef r m, Num a) => TreeCounter r -> m a