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


-- | A pool of connections for Hasql
--   
--   A pool of connections for Hasql
@package hasql-pool
@version 0.6

module Hasql.Pool

-- | A pool of connections to DB.
data Pool

-- | Settings of the connection pool. Consist of:
--   
--   <ul>
--   <li>Pool-size.</li>
--   <li>Timeout. An amount of time in milliseconds for which the unused
--   connections are kept open.</li>
--   <li>Connection settings.</li>
--   </ul>
type Settings = (Int, Int, Settings)

-- | Given the pool-size, timeout and connection settings create a
--   connection-pool.
acquire :: Settings -> IO Pool

-- | Release the connection-pool.
release :: Pool -> IO ()

-- | A union over the connection establishment error and the session error.
data UsageError

-- | Error during an attempt to connect.
ConnectionUsageError :: ConnectionError -> UsageError

-- | Error during session execution.
SessionUsageError :: QueryError -> UsageError

-- | Pool has been released and can no longer be used.
PoolIsReleasedUsageError :: UsageError

-- | Use a connection from the pool to run a session and return the
--   connection to the pool, when finished. If the session fails with
--   <a>ClientError</a> the connection gets reestablished.
use :: Pool -> Session a -> IO (Either UsageError a)
instance GHC.Classes.Eq Hasql.Pool.UsageError
instance GHC.Show.Show Hasql.Pool.UsageError