What

Brief

In the usual gig, we make do with Array.push and Array.shift to play Queue in JavaScript, but here's the kicker – native JavaScript Array isn't exactly Queue VIP. That shift move? It's a bit of a slow dance with a time complexity of linear time complexity O(n). When you're working with big data, you don't want to be caught slow-shifting. So, we roll up our sleeves and craft a Queue that's got a speedy constant time complexity O(1) Queue.enqueue(), a snappy O(1) Queue.dequeue(), and a lightning-fast O(1) Queue.getAt(). Yep, it's Queue-tastic!

more data structures

This is a standalone Queue data structure from the data-structure-typed collection. If you wish to access more data structures or advanced features, you can transition to directly installing the complete data-structure-typed package

How

install

npm

npm i queue-typed --save

yarn

yarn add queue-typed

snippet

TS

import {Queue} from 'queue-typed';
// /* or if you prefer */ import {Queue} from 'queue-typed';

const queue = new Queue<number>();
for (let i = 0; i < magnitude; i++) {
    queue.enqueue(i);
}
for (let i = 0; i < magnitude; i++) {
    queue.dequeue();
}

for (let i = 0; i < magnitude; i++) {
    console.log(queue.getAt(i));        // 0, 1, 2, 3, ...
}

JS

const {Queue} = require('queue-typed');
// /* or if you prefer */ const {Queue} = require('queue-typed');

const queue = new Queue();
for (let i = 0; i < magnitude; i++) {
    queue.enqueue(i);
}
for (let i = 0; i < magnitude; i++) {
    queue.dequeue();
}

for (let i = 0; i < magnitude; i++) {
    console.log(queue.getAt(i));        // 0, 1, 2, 3, ...
}

basic Queue creation and push operation

 // Create a simple Queue with initial values
    const queue = new Queue([1, 2, 3, 4, 5]);

    // Verify the queue maintains insertion order
    console.log([...queue]); // [1, 2, 3, 4, 5];

    // Check length
    console.log(queue.length); // 5;

Queue shift and peek operations

 const queue = new Queue<number>([10, 20, 30, 40]);

    // Peek at the front element without removing it
    console.log(queue.first); // 10;

    // Remove and get the first element (FIFO)
    const first = queue.shift();
    console.log(first); // 10;

    // Verify remaining elements and length decreased
    console.log([...queue]); // [20, 30, 40];
    console.log(queue.length); // 3;

Queue for...of iteration and isEmpty check

 const queue = new Queue<string>(['A', 'B', 'C', 'D']);

    const elements: string[] = [];
    for (const item of queue) {
      elements.push(item);
    }

    // Verify all elements are iterated in order
    console.log(elements); // ['A', 'B', 'C', 'D'];

    // Process all elements
    while (queue.length > 0) {
      queue.shift();
    }

    console.log(queue.length); // 0;

Queue as message broker for event processing

 interface Message {
      id: string;
      type: 'email' | 'sms' | 'push';
      recipient: string;
      content: string;
      timestamp: Date;
    }

    // Create a message queue for real-time event processing
    const messageQueue = new Queue<Message>([
      {
        id: 'msg-001',
        type: 'email',
        recipient: '[email protected]',
        content: 'Welcome!',
        timestamp: new Date()
      },
      {
        id: 'msg-002',
        type: 'sms',
        recipient: '+1234567890',
        content: 'OTP: 123456',
        timestamp: new Date()
      },
      {
        id: 'msg-003',
        type: 'push',
        recipient: 'device-token-xyz',
        content: 'New notification',
        timestamp: new Date()
      },
      {
        id: 'msg-004',
        type: 'email',
        recipient: '[email protected]',
        content: 'Daily report',
        timestamp: new Date()
      }
    ]);

    // Process messages in FIFO order (first message first)
    const processedMessages: string[] = [];
    while (messageQueue.length > 0) {
      const message = messageQueue.shift();
      if (message) {
        processedMessages.push(`${message.type}:${message.recipient}`);
      }
    }

    // Verify messages were processed in order
    console.log(processedMessages); // [
 //      'email:[email protected]',
 //      'sms:+1234567890',
 //      'push:device-token-xyz',
 //      'email:[email protected]'
 //    ];

    // Queue should be empty after processing all messages
    console.log(messageQueue.length); // 0;

API docs & Examples

API Docs

Live Examples

Examples Repository

Data Structures

Standard library data structure comparison

Benchmark

Built-in classic algorithms

Software Engineering Design Standards