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


-- | Parallel Tree Search
--   
--   This Haskell library provides an implementation of parallel search
--   based on the search tree provided by the package tree-monad.
@package parallel-tree-search
@version 0.2


-- | This Haskell library provides an implementation of parallel search
--   based on the search tree provided by the package tree-monad.
module Control.Concurrent.ParallelTreeSearch

-- | Search queues store multiple search trees.
class SearchQueue q
emptyQ :: (SearchQueue q) => q a
addQ :: (SearchQueue q) => SearchTree a -> q a -> q a
viewQ :: (SearchQueue q) => q a -> SearchView q a

-- | A <tt>SearchView</tt> is used for pattern matching a search queue.
data SearchView q a
EmptyQ :: SearchView q a
(:~) :: SearchTree a -> q a -> SearchView q a

-- | LIFO search queues can be used to implement parallel depth-first
--   search.
newtype LIFO a
LIFO :: [SearchTree a] -> LIFO a

-- | FIFO search queues can be used to implement parallel breadth-first
--   search.
newtype FIFO a
FIFO :: (Seq (SearchTree a)) -> FIFO a

-- | This function enumerates the results stored in the queue of
--   <tt>SearchTree</tt>s in parallel. It is parameterised by the maximum
--   number of threads to use and the maximum amount of work to perform by
--   each thread before communicating the results.
parallelTreeSearch :: (SearchQueue q) => Int -> Int -> q a -> IO [a]
instance SearchQueue FIFO
instance SearchQueue LIFO