@ch1nm4y-8/simple-queue-js

A lightweight FIFO queue for JavaScript and TypeScript.

Features

• Zero runtime dependencies
• FIFO (First In, First Out)
• Full TypeScript support with type declarations
• Supports ESM (import)
• Supports CommonJS (require)
• Iterable (for...of, Array.from, spread operator)
• Clone support
• Array conversion support

Install

npm install @ch1nm4y-8/simple-queue-js

TypeScript

import { Queue } from "@ch1nm4y-8/simple-queue-js";

const queue = new Queue<number>();

queue.enqueue(1);
queue.enqueue(2);
queue.enqueue(3);

console.log(queue.dequeue()); // 1
console.log(queue.peek()); // 2
console.log(queue.size()); // 2

Constructor

const queue1 = new Queue([1, 2, 3]);
const queue2 = new Queue(new Set([1, 2, 3]));

console.log(queue1.dequeue()); // 1

Iteration

const queue = new Queue([1, 2, 3]);

for (const item of queue) {
  console.log(item);
}
// 1
// 2
// 3

Type Safety

const queue = new Queue<number>();

queue.enqueue(1);

// Type Error
queue.enqueue("hello");

ECMAScript Modules (ESM)

import { Queue } from "@ch1nm4y-8/simple-queue-js";

const queue = new Queue();

queue.enqueue("A");
queue.enqueue("B");

console.log(queue.dequeue()); // A

CommonJS

const { Queue } = require("@ch1nm4y-8/simple-queue-js");

const queue = new Queue();

queue.enqueue("A");
queue.enqueue("B");

console.log(queue.dequeue()); // A

API

| Method | Time Complexity | Description | | ---------------- | --------------- | ------------------------------------------ | | enqueue(value) | O(1) | Adds an item to the back of the queue | | dequeue() | O(1) amortized | Removes and returns the front item | | peek() | O(1) | Returns the front item without removing it | | clear() | O(1) | Removes all items | | size() | O(1) | Returns the number of items | | isEmpty() | O(1) | Returns whether the queue is empty | | toArray() | O(n) | Converts the queue to an array | | clone() | O(n) | Returns a shallow copy of the queue |

enqueue(value)

Adds an item to the back of the queue.

queue.enqueue(1);

Returns:

this;

dequeue()

Removes and returns the front item.

const value = queue.dequeue();

Returns:

T | undefined;

peek()

Returns the front item without removing it.

const value = queue.peek();

Returns:

T | undefined;

clear()

Removes all items from the queue.

queue.clear();

Returns:

void

size()

Returns the number of items in the queue.

console.log(queue.size());

Returns:

number;

isEmpty()

Returns whether the queue is empty.

console.log(queue.isEmpty());

Returns:

boolean;

toArray()

const queue = new Queue([1, 2, 3]);
console.log(queue.toArray()); // [1, 2, 3]

clone()

const q1 = new Queue([1, 2, 3]);
const q2 = q1.clone();

q1.dequeue();

console.log(q1.toArray()); // [2, 3]
console.log(q2.toArray()); // [1, 2, 3]

Example

import { Queue } from "@ch1nm4y-8/simple-queue-js";

const tasks = new Queue<string>();

tasks.enqueue("Build");
tasks.enqueue("Test");
tasks.enqueue("Deploy");

while (!tasks.isEmpty()) {
  console.log(tasks.dequeue());
}

Output:

Build
Test
Deploy

License

MIT