Copyright | Copyright (c) 2009-2017 David Sorokin <david.sorokin@gmail.com> |
---|---|

License | BSD3 |

Maintainer | David Sorokin <david.sorokin@gmail.com> |

Stability | experimental |

Safe Haskell | None |

Language | Haskell2010 |

Tested with: GHC 8.0.1

This module defines a queue that can use the specified strategies. So, having only
the `FCFS`

, `LCFS`

, `SIRO`

and `StaticPriorities`

strategies, you can build
4 x 4 x 4 = 64 different types of the queue, each of them will have its own
behaviour.

- type FCFSQueue a = Queue FCFS FCFS FCFS a
- type LCFSQueue a = Queue FCFS LCFS FCFS a
- type SIROQueue a = Queue FCFS SIRO FCFS a
- type PriorityQueue a = Queue FCFS StaticPriorities FCFS a
- data Queue si sm so a
- newFCFSQueue :: Int -> Event (FCFSQueue a)
- newLCFSQueue :: Int -> Event (LCFSQueue a)
- newSIROQueue :: Int -> Event (SIROQueue a)
- newPriorityQueue :: Int -> Event (PriorityQueue a)
- newQueue :: (QueueStrategy si, QueueStrategy sm, QueueStrategy so) => si -> sm -> so -> Int -> Event (Queue si sm so a)
- enqueueStrategy :: Queue si sm so a -> si
- enqueueStoringStrategy :: Queue si sm so a -> sm
- dequeueStrategy :: Queue si sm so a -> so
- queueNull :: Queue si sm so a -> Event Bool
- queueFull :: Queue si sm so a -> Event Bool
- queueMaxCount :: Queue si sm so a -> Int
- queueCount :: Queue si sm so a -> Event Int
- queueCountStats :: Queue si sm so a -> Event (TimingStats Int)
- enqueueCount :: Queue si sm so a -> Event Int
- enqueueLostCount :: Queue si sm so a -> Event Int
- enqueueStoreCount :: Queue si sm so a -> Event Int
- dequeueCount :: Queue si sm so a -> Event Int
- dequeueExtractCount :: Queue si sm so a -> Event Int
- queueLoadFactor :: Queue si sm so a -> Event Double
- enqueueRate :: Queue si sm so a -> Event Double
- enqueueStoreRate :: Queue si sm so a -> Event Double
- dequeueRate :: Queue si sm so a -> Event Double
- dequeueExtractRate :: Queue si sm so a -> Event Double
- queueWaitTime :: Queue si sm so a -> Event (SamplingStats Double)
- queueTotalWaitTime :: Queue si sm so a -> Event (SamplingStats Double)
- enqueueWaitTime :: Queue si sm so a -> Event (SamplingStats Double)
- dequeueWaitTime :: Queue si sm so a -> Event (SamplingStats Double)
- queueRate :: Queue si sm so a -> Event Double
- dequeue :: (DequeueStrategy si, DequeueStrategy sm, EnqueueStrategy so) => Queue si sm so a -> Process a
- dequeueWithOutputPriority :: (DequeueStrategy si, DequeueStrategy sm, PriorityQueueStrategy so po) => Queue si sm so a -> po -> Process a
- tryDequeue :: (DequeueStrategy si, DequeueStrategy sm) => Queue si sm so a -> Event (Maybe a)
- enqueue :: (EnqueueStrategy si, EnqueueStrategy sm, DequeueStrategy so) => Queue si sm so a -> a -> Process ()
- enqueueWithInputPriority :: (PriorityQueueStrategy si pi, EnqueueStrategy sm, DequeueStrategy so) => Queue si sm so a -> pi -> a -> Process ()
- enqueueWithStoringPriority :: (EnqueueStrategy si, PriorityQueueStrategy sm pm, DequeueStrategy so) => Queue si sm so a -> pm -> a -> Process ()
- enqueueWithInputStoringPriorities :: (PriorityQueueStrategy si pi, PriorityQueueStrategy sm pm, DequeueStrategy so) => Queue si sm so a -> pi -> pm -> a -> Process ()
- tryEnqueue :: (EnqueueStrategy sm, DequeueStrategy so) => Queue si sm so a -> a -> Event Bool
- tryEnqueueWithStoringPriority :: (PriorityQueueStrategy sm pm, DequeueStrategy so) => Queue si sm so a -> pm -> a -> Event Bool
- enqueueOrLost :: (EnqueueStrategy sm, DequeueStrategy so) => Queue si sm so a -> a -> Event Bool
- enqueueOrLost_ :: (EnqueueStrategy sm, DequeueStrategy so) => Queue si sm so a -> a -> Event ()
- enqueueWithStoringPriorityOrLost :: (PriorityQueueStrategy sm pm, DequeueStrategy so) => Queue si sm so a -> pm -> a -> Event Bool
- enqueueWithStoringPriorityOrLost_ :: (PriorityQueueStrategy sm pm, DequeueStrategy so) => Queue si sm so a -> pm -> a -> Event ()
- queueDelete :: (Eq a, DequeueStrategy si, DeletingQueueStrategy sm, DequeueStrategy so) => Queue si sm so a -> a -> Event Bool
- queueDelete_ :: (Eq a, DequeueStrategy si, DeletingQueueStrategy sm, DequeueStrategy so) => Queue si sm so a -> a -> Event ()
- queueDeleteBy :: (DequeueStrategy si, DeletingQueueStrategy sm, DequeueStrategy so) => Queue si sm so a -> (a -> Bool) -> Event (Maybe a)
- queueDeleteBy_ :: (DequeueStrategy si, DeletingQueueStrategy sm, DequeueStrategy so) => Queue si sm so a -> (a -> Bool) -> Event ()
- queueContains :: (Eq a, DeletingQueueStrategy sm) => Queue si sm so a -> a -> Event Bool
- queueContainsBy :: DeletingQueueStrategy sm => Queue si sm so a -> (a -> Bool) -> Event (Maybe a)
- clearQueue :: (DequeueStrategy si, DequeueStrategy sm) => Queue si sm so a -> Event ()
- resetQueue :: Queue si sm so a -> Event ()
- waitWhileFullQueue :: Queue si sm so a -> Process ()
- queueSummary :: (Show si, Show sm, Show so) => Queue si sm so a -> Int -> Event ShowS
- queueNullChanged :: Queue si sm so a -> Signal Bool
- queueNullChanged_ :: Queue si sm so a -> Signal ()
- queueFullChanged :: Queue si sm so a -> Signal Bool
- queueFullChanged_ :: Queue si sm so a -> Signal ()
- queueCountChanged :: Queue si sm so a -> Signal Int
- queueCountChanged_ :: Queue si sm so a -> Signal ()
- enqueueCountChanged :: Queue si sm so a -> Signal Int
- enqueueCountChanged_ :: Queue si sm so a -> Signal ()
- enqueueLostCountChanged :: Queue si sm so a -> Signal Int
- enqueueLostCountChanged_ :: Queue si sm so a -> Signal ()
- enqueueStoreCountChanged :: Queue si sm so a -> Signal Int
- enqueueStoreCountChanged_ :: Queue si sm so a -> Signal ()
- dequeueCountChanged :: Queue si sm so a -> Signal Int
- dequeueCountChanged_ :: Queue si sm so a -> Signal ()
- dequeueExtractCountChanged :: Queue si sm so a -> Signal Int
- dequeueExtractCountChanged_ :: Queue si sm so a -> Signal ()
- queueLoadFactorChanged :: Queue si sm so a -> Signal Double
- queueLoadFactorChanged_ :: Queue si sm so a -> Signal ()
- queueWaitTimeChanged :: Queue si sm so a -> Signal (SamplingStats Double)
- queueWaitTimeChanged_ :: Queue si sm so a -> Signal ()
- queueTotalWaitTimeChanged :: Queue si sm so a -> Signal (SamplingStats Double)
- queueTotalWaitTimeChanged_ :: Queue si sm so a -> Signal ()
- enqueueWaitTimeChanged :: Queue si sm so a -> Signal (SamplingStats Double)
- enqueueWaitTimeChanged_ :: Queue si sm so a -> Signal ()
- dequeueWaitTimeChanged :: Queue si sm so a -> Signal (SamplingStats Double)
- dequeueWaitTimeChanged_ :: Queue si sm so a -> Signal ()
- queueRateChanged :: Queue si sm so a -> Signal Double
- queueRateChanged_ :: Queue si sm so a -> Signal ()
- enqueueInitiated :: Queue si sm so a -> Signal a
- enqueueStored :: Queue si sm so a -> Signal a
- enqueueLost :: Queue si sm so a -> Signal a
- dequeueRequested :: Queue si sm so a -> Signal ()
- dequeueExtracted :: Queue si sm so a -> Signal a
- queueChanged_ :: Queue si sm so a -> Signal ()

# Queue Types

type FCFSQueue a = Queue FCFS FCFS FCFS a Source #

A type synonym for the ordinary FIFO queue also known as the FCFS (First Come - First Serviced) queue.

type LCFSQueue a = Queue FCFS LCFS FCFS a Source #

A type synonym for the ordinary LIFO queue also known as the LCFS (Last Come - First Serviced) queue.

type SIROQueue a = Queue FCFS SIRO FCFS a Source #

A type synonym for the SIRO (Serviced in Random Order) queue.

type PriorityQueue a = Queue FCFS StaticPriorities FCFS a Source #

A type synonym for the queue with static priorities applied when storing the elements in the queue.

data Queue si sm so a Source #

Represents a queue using the specified strategies for enqueueing (input), `si`

,
internal storing (in memory), `sm`

, and dequeueing (output), `so`

, where `a`

denotes
the type of items stored in the queue.

(Show si, Show sm, Show so, ResultItemable (ResultValue si), ResultItemable (ResultValue sm), ResultItemable (ResultValue so)) => ResultProvider (Queue si sm so a) Source # | |

# Creating Queue

newFCFSQueue :: Int -> Event (FCFSQueue a) Source #

Create a new FCFS queue with the specified capacity.

newLCFSQueue :: Int -> Event (LCFSQueue a) Source #

Create a new LCFS queue with the specified capacity.

newSIROQueue :: Int -> Event (SIROQueue a) Source #

Create a new SIRO queue with the specified capacity.

newPriorityQueue :: Int -> Event (PriorityQueue a) Source #

Create a new priority queue with the specified capacity.

:: (QueueStrategy si, QueueStrategy sm, QueueStrategy so) | |

=> si | the strategy applied to the enqueueing (input) processes when the queue is full |

-> sm | the strategy applied when storing items in the queue |

-> so | the strategy applied to the dequeueing (output) processes when the queue is empty |

-> Int | the queue capacity |

-> Event (Queue si sm so a) |

Create a new queue with the specified strategies and capacity.

# Queue Properties and Activities

enqueueStrategy :: Queue si sm so a -> si Source #

The strategy applied to the enqueueing (input) processes when the queue is full.

enqueueStoringStrategy :: Queue si sm so a -> sm Source #

The strategy applied when storing (in memory) items in the queue.

dequeueStrategy :: Queue si sm so a -> so Source #

The strategy applied to the dequeueing (output) processes when the queue is empty.

queueNull :: Queue si sm so a -> Event Bool Source #

Test whether the queue is empty.

See also `queueNullChanged`

and `queueNullChanged_`

.

queueFull :: Queue si sm so a -> Event Bool Source #

Test whether the queue is full.

See also `queueFullChanged`

and `queueFullChanged_`

.

queueMaxCount :: Queue si sm so a -> Int Source #

The queue capacity.

queueCount :: Queue si sm so a -> Event Int Source #

Return the current queue size.

See also `queueCountStats`

, `queueCountChanged`

and `queueCountChanged_`

.

queueCountStats :: Queue si sm so a -> Event (TimingStats Int) Source #

Return the queue size statistics.

enqueueCount :: Queue si sm so a -> Event Int Source #

Return the total number of input items that were enqueued.

See also `enqueueCountChanged`

and `enqueueCountChanged_`

.

enqueueLostCount :: Queue si sm so a -> Event Int Source #

Return the number of lost items.

See also `enqueueLostCountChanged`

and `enqueueLostCountChanged_`

.

enqueueStoreCount :: Queue si sm so a -> Event Int Source #

Return the total number of input items that were stored.

See also `enqueueStoreCountChanged`

and `enqueueStoreCountChanged_`

.

dequeueCount :: Queue si sm so a -> Event Int Source #

Return the total number of requests for dequeueing the items, not taking into account the failed attempts to dequeue immediately without suspension.

See also `dequeueCountChanged`

and `dequeueCountChanged_`

.

dequeueExtractCount :: Queue si sm so a -> Event Int Source #

Return the total number of output items that were actually dequeued.

See also `dequeueExtractCountChanged`

and `dequeueExtractCountChanged_`

.

queueLoadFactor :: Queue si sm so a -> Event Double Source #

Return the load factor: the queue size divided by its maximum size.

See also `queueLoadFactorChanged`

and `queueLoadFactorChanged_`

.

enqueueRate :: Queue si sm so a -> Event Double Source #

Return the rate of the input items that were enqueued: how many items per time.

enqueueStoreRate :: Queue si sm so a -> Event Double Source #

Return the rate of the items that were stored: how many items per time.

dequeueRate :: Queue si sm so a -> Event Double Source #

Return the rate of the requests for dequeueing the items: how many requests per time. It does not include the failed attempts to dequeue immediately without suspension.

dequeueExtractRate :: Queue si sm so a -> Event Double Source #

Return the rate of the output items that were actually dequeued: how many items per time.

queueWaitTime :: Queue si sm so a -> Event (SamplingStats Double) Source #

Return the wait time from the time at which the item was stored in the queue to the time at which it was dequeued.

See also `queueWaitTimeChanged`

and `queueWaitTimeChanged_`

.

queueTotalWaitTime :: Queue si sm so a -> Event (SamplingStats Double) Source #

Return the total wait time from the time at which the enqueueing operation was initiated to the time at which the item was dequeued.

In some sense, `queueTotalWaitTime == enqueueWaitTime + queueWaitTime`

.

See also `queueTotalWaitTimeChanged`

and `queueTotalWaitTimeChanged_`

.

enqueueWaitTime :: Queue si sm so a -> Event (SamplingStats Double) Source #

Return the enqueue wait time from the time at which the enqueueing operation was initiated to the time at which the item was stored in the queue.

See also `enqueueWaitTimeChanged`

and `enqueueWaitTimeChanged_`

.

dequeueWaitTime :: Queue si sm so a -> Event (SamplingStats Double) Source #

Return the dequeue wait time from the time at which the item was requested for dequeueing to the time at which it was actually dequeued.

See also `dequeueWaitTimeChanged`

and `dequeueWaitTimeChanged_`

.

queueRate :: Queue si sm so a -> Event Double Source #

Return a long-term average queue rate calculated as the average queue size divided by the average wait time.

This value may be less than the actual arrival rate as the queue is finite and new arrivals may be locked while the queue remains full.

See also `queueRateChanged`

and `queueRateChanged_`

.

# Dequeuing and Enqueuing

:: (DequeueStrategy si, DequeueStrategy sm, EnqueueStrategy so) | |

=> Queue si sm so a | the queue |

-> Process a | the dequeued value |

Dequeue suspending the process if the queue is empty.

dequeueWithOutputPriority Source #

:: (DequeueStrategy si, DequeueStrategy sm, PriorityQueueStrategy so po) | |

=> Queue si sm so a | the queue |

-> po | the priority for output |

-> Process a | the dequeued value |

Dequeue with the output priority suspending the process if the queue is empty.

:: (DequeueStrategy si, DequeueStrategy sm) | |

=> Queue si sm so a | the queue |

-> Event (Maybe a) | the dequeued value of |

Try to dequeue immediately.

:: (EnqueueStrategy si, EnqueueStrategy sm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> a | the item to enqueue |

-> Process () |

Enqueue the item suspending the process if the queue is full.

enqueueWithInputPriority Source #

:: (PriorityQueueStrategy si pi, EnqueueStrategy sm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> pi | the priority for input |

-> a | the item to enqueue |

-> Process () |

Enqueue with the input priority the item suspending the process if the queue is full.

enqueueWithStoringPriority Source #

:: (EnqueueStrategy si, PriorityQueueStrategy sm pm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> pm | the priority for storing |

-> a | the item to enqueue |

-> Process () |

Enqueue with the storing priority the item suspending the process if the queue is full.

enqueueWithInputStoringPriorities Source #

:: (PriorityQueueStrategy si pi, PriorityQueueStrategy sm pm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> pi | the priority for input |

-> pm | the priority for storing |

-> a | the item to enqueue |

-> Process () |

Enqueue with the input and storing priorities the item suspending the process if the queue is full.

:: (EnqueueStrategy sm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> a | the item which we try to enqueue |

-> Event Bool |

Try to enqueue the item. Return `False`

in the monad if the queue is full.

tryEnqueueWithStoringPriority Source #

:: (PriorityQueueStrategy sm pm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> pm | the priority for storing |

-> a | the item which we try to enqueue |

-> Event Bool |

Try to enqueue with the storing priority the item. Return `False`

in
the monad if the queue is full.

:: (EnqueueStrategy sm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> a | the item which we try to enqueue |

-> Event Bool |

Try to enqueue the item. If the queue is full then the item will be lost
and `False`

will be returned.

:: (EnqueueStrategy sm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> a | the item which we try to enqueue |

-> Event () |

Try to enqueue the item. If the queue is full then the item will be lost.

enqueueWithStoringPriorityOrLost Source #

:: (PriorityQueueStrategy sm pm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> pm | the priority for storing |

-> a | the item which we try to enqueue |

-> Event Bool |

Try to enqueue with the storing priority the item. If the queue is full
then the item will be lost and `False`

will be returned.

enqueueWithStoringPriorityOrLost_ Source #

:: (PriorityQueueStrategy sm pm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> pm | the priority for storing |

-> a | the item which we try to enqueue |

-> Event () |

Try to enqueue with the storing priority the item. If the queue is full then the item will be lost.

:: (Eq a, DequeueStrategy si, DeletingQueueStrategy sm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> a | the item to remove from the queue |

-> Event Bool | whether the item was found and removed |

Remove the item from the queue and return a flag indicating whether the item was found and actually removed.

:: (Eq a, DequeueStrategy si, DeletingQueueStrategy sm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> a | the item to remove from the queue |

-> Event () |

Remove the specified item from the queue.

:: (DequeueStrategy si, DeletingQueueStrategy sm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> (a -> Bool) | the predicate |

-> Event (Maybe a) |

Remove an item satisfying the specified predicate and return the item if found.

:: (DequeueStrategy si, DeletingQueueStrategy sm, DequeueStrategy so) | |

=> Queue si sm so a | the queue |

-> (a -> Bool) | the predicate |

-> Event () |

Remove an item satisfying the specified predicate.

:: (Eq a, DeletingQueueStrategy sm) | |

=> Queue si sm so a | the queue |

-> a | the item to search the queue for |

-> Event Bool | whether the item was found |

Detect whether the item is contained in the queue.

:: DeletingQueueStrategy sm | |

=> Queue si sm so a | the queue |

-> (a -> Bool) | the predicate |

-> Event (Maybe a) | the item if it was found |

Detect whether an item satisfying the specified predicate is contained in the queue.

:: (DequeueStrategy si, DequeueStrategy sm) | |

=> Queue si sm so a | the queue |

-> Event () |

Clear the queue immediately.

# Statistics Reset

resetQueue :: Queue si sm so a -> Event () Source #

Reset the statistics.

# Awaiting

waitWhileFullQueue :: Queue si sm so a -> Process () Source #

Wait while the queue is full.

# Summary

queueSummary :: (Show si, Show sm, Show so) => Queue si sm so a -> Int -> Event ShowS Source #

Return the summary for the queue with desciption of its properties and activities using the specified indent.

# Derived Signals for Properties

queueNullChanged :: Queue si sm so a -> Signal Bool Source #

Signal when the `queueNull`

property value has changed.

queueNullChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `queueNull`

property value has changed.

queueFullChanged :: Queue si sm so a -> Signal Bool Source #

Signal when the `queueFull`

property value has changed.

queueFullChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `queueFull`

property value has changed.

queueCountChanged :: Queue si sm so a -> Signal Int Source #

Signal when the `queueCount`

property value has changed.

queueCountChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `queueCount`

property value has changed.

enqueueCountChanged :: Queue si sm so a -> Signal Int Source #

Signal when the `enqueueCount`

property value has changed.

enqueueCountChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `enqueueCount`

property value has changed.

enqueueLostCountChanged :: Queue si sm so a -> Signal Int Source #

Signal when the `enqueueLostCount`

property value has changed.

enqueueLostCountChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `enqueueLostCount`

property value has changed.

enqueueStoreCountChanged :: Queue si sm so a -> Signal Int Source #

Signal when the `enqueueStoreCount`

property value has changed.

enqueueStoreCountChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `enqueueStoreCount`

property value has changed.

dequeueCountChanged :: Queue si sm so a -> Signal Int Source #

Signal when the `dequeueCount`

property value has changed.

dequeueCountChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `dequeueCount`

property value has changed.

dequeueExtractCountChanged :: Queue si sm so a -> Signal Int Source #

Signal when the `dequeueExtractCount`

property value has changed.

dequeueExtractCountChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `dequeueExtractCount`

property value has changed.

queueLoadFactorChanged :: Queue si sm so a -> Signal Double Source #

Signal when the `queueLoadFactor`

property value has changed.

queueLoadFactorChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `queueLoadFactor`

property value has changed.

queueWaitTimeChanged :: Queue si sm so a -> Signal (SamplingStats Double) Source #

Signal when the `queueWaitTime`

property value has changed.

queueWaitTimeChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `queueWaitTime`

property value has changed.

queueTotalWaitTimeChanged :: Queue si sm so a -> Signal (SamplingStats Double) Source #

Signal when the `queueTotalWaitTime`

property value has changed.

queueTotalWaitTimeChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `queueTotalWaitTime`

property value has changed.

enqueueWaitTimeChanged :: Queue si sm so a -> Signal (SamplingStats Double) Source #

Signal when the `enqueueWaitTime`

property value has changed.

enqueueWaitTimeChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `enqueueWaitTime`

property value has changed.

dequeueWaitTimeChanged :: Queue si sm so a -> Signal (SamplingStats Double) Source #

Signal when the `dequeueWaitTime`

property value has changed.

dequeueWaitTimeChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `dequeueWaitTime`

property value has changed.

queueRateChanged :: Queue si sm so a -> Signal Double Source #

Signal when the `queueRate`

property value has changed.

queueRateChanged_ :: Queue si sm so a -> Signal () Source #

Signal when the `queueRate`

property value has changed.

# Basic Signals

enqueueInitiated :: Queue si sm so a -> Signal a Source #

Return a signal that notifies when the enqueuing operation is initiated.

enqueueStored :: Queue si sm so a -> Signal a Source #

Return a signal that notifies when the enqueuing operation is completed and the item is stored in the internal memory of the queue.

enqueueLost :: Queue si sm so a -> Signal a Source #

Return a signal which notifies that the item was lost when
attempting to add it to the full queue with help of
`enqueueOrLost`

, `enqueueOrLost_`

or similar functions that imply
that the element can be lost. All their names are ending with `OrLost`

or `OrLost_`

.

In other cases the enqueued items are not lost but the corresponded process
can suspend until the internal queue storage is freed. Although there is one
exception from this rule. If the process trying to enqueue a new element was
suspended but then canceled through `cancelProcess`

from the outside then
the item will not be added.

dequeueRequested :: Queue si sm so a -> Signal () Source #

Return a signal that notifies when the dequeuing operation was requested.

dequeueExtracted :: Queue si sm so a -> Signal a Source #

Return a signal that notifies when the item was extracted from the internal storage of the queue and prepared for immediate receiving by the dequeuing process.

# Overall Signal

queueChanged_ :: Queue si sm so a -> Signal () Source #

Signal whenever any property of the queue changes.

The property must have the corresponded signal. There are also characteristics similar to the properties but that have no signals. As a rule, such characteristics already depend on the simulation time and therefore they may change at any time point.