Concurrency.TBQueue

Documentation

data TBQueue a

TBQueue is an abstract type representing a bounded FIFO channel.

Since: stm-2.4

Instances

Eq (TBQueue a)

Defined in Control.Concurrent.STM.TBQueue

Methods

(==) :: TBQueue a -> TBQueue a -> Bool

(/=) :: TBQueue a -> TBQueue a -> Bool

newTBQueue

Arguments

:: Natural

maximum number of elements the queue can hold

-> STM (TBQueue a)

Builds and returns a new instance of TBQueue.

newTBQueueIO :: MonadIO m => Natural -> m (TBQueue a)

Lifted version of newTBQueueIO

Since: unliftio-0.2.1.0

readTBQueue :: TBQueue a -> STM a

Read the next value from the TBQueue.

tryReadTBQueue :: TBQueue a -> STM (Maybe a)

A version of readTBQueue which does not retry. Instead it returns Nothing if no value is available.

flushTBQueue :: TBQueue a -> STM [a]

Efficiently read the entire contents of a TBQueue into a list. This function never retries.

Since: stm-2.4.5

peekTBQueue :: TBQueue a -> STM a

Get the next value from the TBQueue without removing it, retrying if the channel is empty.

tryPeekTBQueue :: TBQueue a -> STM (Maybe a)

A version of peekTBQueue which does not retry. Instead it returns Nothing if no value is available.

writeTBQueue :: TBQueue a -> a -> STM ()

Write a value to a TBQueue; blocks if the queue is full.

unGetTBQueue :: TBQueue a -> a -> STM ()

Put a data item back onto a channel, where it will be the next item read. Blocks if the queue is full.

isEmptyTBQueue :: TBQueue a -> STM Bool

Returns True if the supplied TBQueue is empty.

isFullTBQueue :: TBQueue a -> STM Bool

Returns True if the supplied TBQueue is full.

Since: stm-2.4.3

lengthTBQueue :: TBQueue a -> STM Natural

Return the length of a TBQueue.

Since: stm-2.5.0.0