[Home](./index.md) > [@empathyco/x-components](./x-components.md) > [BaseXPriorityQueue](./x-components.basexpriorityqueue.md) ## BaseXPriorityQueue class . Default [XPriorityQueue](./x-components.xpriorityqueue.md) implementation. Method big-O \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\- - push O(n) - pop O(1) - peek O(1) - at O(1) **Signature:** ```typescript export declare class BaseXPriorityQueue implements XPriorityQueue ``` **Implements:** [XPriorityQueue](./x-components.xpriorityqueue.md)<SomeRecord, SomeData> ## Constructors

Constructor	Modifiers	Description
[(constructor)(comparatorFn)](./x-components.basexpriorityqueue._constructor_.md)		Creates a new [XPriorityQueue](./x-components.xpriorityqueue.md).

## Properties

Property	Modifiers	Type	Description
[keys](./x-components.basexpriorityqueue.keys.md)	`readonly`	(keyof SomeRecord)\[\]	The `keys` property of a [XPriorityQueue](./x-components.xpriorityqueue.md) represents the keys of that queue. The value is an array of the parametrized `Key` type.

## Methods

Method	Modifiers	Description
[at(index)](./x-components.basexpriorityqueue.at.md)		Retrieves the [node](./x-components.xpriorityqueuenode.md) at a given position.
[clear()](./x-components.basexpriorityqueue.clear.md)		Removes all the [nodes](./x-components.xpriorityqueuenode.md) from the queue.
[isEmpty()](./x-components.basexpriorityqueue.isempty.md)		Checks if the queue is empty.
[peek()](./x-components.basexpriorityqueue.peek.md)		Retrieves, but does not remove, the head [node](./x-components.xpriorityqueuenode.md) of the queue.
[pop()](./x-components.basexpriorityqueue.pop.md)		See [XPriorityQueue.pop](./x-components.xpriorityqueue.pop.md).
[push(key, priority, data)](./x-components.basexpriorityqueue.push.md)		. See [XPriorityQueue.push](./x-components.xpriorityqueue.push.md).
[size()](./x-components.basexpriorityqueue.size.md)		Retrieves the number of [nodes](./x-components.xpriorityqueuenode.md) stored in the queue.
[toString()](./x-components.basexpriorityqueue.tostring.md)		Returns a string representation of this collection. The string representation consists of a list of the queue [nodes](./x-components.xpriorityqueuenode.md) split in multiple lines, one for each one. Nodes are converted to strings as by toString().