# cp.collect.Queue

A "double-ended queue" implementation. This allows pushing and popping values to the left or right side of the queue. This can be used for classic 'stack' and 'queue' uses - for a stack, push and pop from one end, for a queue, push and pop from opposite ends.

# will always return the size of the queue.

The left-most item in the queue wil always be at index 1, the right-most will be at index #.

You can iterate via ipairs, but as with all tables, the queue contains any nil values, it will stop at that point. To iterate the whole queue, you need to use the # operator. Eg:

local q = Queue(1, nil, 3)
for i,v in ipairs(q) do print(v) end  -- Outputs "1"
for i = 1, #q do print(v) end -- Outputs "1", "nil", "3"

# API Overview

Functions - API calls offered directly by the extension

contains
len
peekLeft
peekRight
popLeft
popRight
pushLeft
pushRight
removeItem
removeItem

Constructors - API calls which return an object, typically one that offers API methods

Methods - API calls which can only be made on an object returned by a constructor

contains
len
peekLeft
peekRight
popLeft
popRight
pushLeft
pushRight

# API Documentation

# Functions

# contains


Signature	`cp.collect.Queue.contains(queue, item) -> boolean`
Type	Function
Description	Checks if the `queue` contains the specified `item`.
Parameters	queue - The queue to check. item - The item to check for.
Returns	`true` if the item is in the queue.
Notes	None
Examples	None
Source	src/extensions/cp/collect/Queue.lua line 181

# len


Signature	`cp.collect.Queue.len(queue) -> anything`
Type	Function
Description	Returns the number of items in the queue.
Parameters	queue - The queue to check.
Returns	The total number of items.
Notes	None
Examples	None
Source	src/extensions/cp/collect/Queue.lua line 244

# peekLeft


Signature	`cp.collect.Queue.peekLeft(queue) -> anything`
Type	Function
Description	Returns the left-most value from the `queue` without removig it.
Parameters	queue - The queue to peek into.
Returns	The left-most value of the `Queue`.
Notes	None
Examples	None
Source	src/extensions/cp/collect/Queue.lua line 147

# peekRight


Signature	`cp.collect.Queue.peekRight(queue) -> anything`
Type	Function
Description	Returns the right-most value from the `queue` without removig it.
Parameters	queue - The queue to peek into.
Returns	The right-most value of the `Queue`.
Notes	None
Examples	None
Source	src/extensions/cp/collect/Queue.lua line 164

# popLeft


Signature	`cp.collect.Queue.popLeft(queue) -> anything`
Type	Function
Description	Removes the left-most value from the `queue` and returns it.
Parameters	queue - The queue to pop from.
Returns	The left-most value of the `Queue`.
Notes	None
Examples	None
Source	src/extensions/cp/collect/Queue.lua line 105

# popRight


Signature	`cp.collect.Queue.popRight(queue) -> anything`
Type	Function
Description	Removes the right-most value from the `queue` and returns it.
Parameters	queue - The queue to pop from.
Returns	The right-most value of the `Queue`.
Notes	None
Examples	None
Source	src/extensions/cp/collect/Queue.lua line 126

# pushLeft


Signature	`cp.collect.Queue.pushLeft(queue, ...) -> cp.collect.Queue`
Type	Function
Description	Pushes the values to the left side of the `queue`.
Parameters	queue - The queue to push into. ... - The values to push.
Returns	The same `Queue` instance.
Notes	If there are multiple values, then they will be added from right to left. That is to say, the left-most of the new values will be the left-most value of the queue.
Examples	None
Source	src/extensions/cp/collect/Queue.lua line 54

# pushRight


Signature	`cp.collect.Queue.pushRight(queue, ...) -> cp.collect.Queue`
Type	Function
Description	Pushes the values to the right side of the `queue`.
Parameters	queue - The queue to push into. ... - The values to push.
Returns	The same `Queue` instance.
Notes	If there are multiple values, then they will be added from left to right. That is to say, the right-most of the new values will be the right-most value of the queue.
Examples	None
Source	src/extensions/cp/collect/Queue.lua line 80

# removeItem


Signature	`cp.collect.Queue.removeItem(queue, item) -> number`
Type	Function
Description	Attempts to remove the specified item from the queue.
Parameters	queue - The queue to modify. item - The item to remove, if present.
Returns	The index of the item, or `nil` if not found.
Notes	This call may be very expensive if there are many items in the queue after the specified item. If the item was found, the index it was found at is returned. If not, `nil` is returned.
Examples	None
Source	src/extensions/cp/collect/Queue.lua line 201