Implementing Tuples in JavaScript – onlinecode

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Implementing Tuples in JavaScript

In this post, we will give you information about Implementing Tuples in JavaScript. Here we will give you detail about Implementing Tuples in JavaScript And how to use it also give you a demo for it if it is necessary.

In JavaScript, a tuple is effectively an immutable array of primitives with known length.
You can use a plain JavaScript array as a tuple to handle cases like returning multiple values as follows.

function getCoordinates() {
  const x = 1;
  const y = 2;
  const z = 3;

  return [x, y, z];
}

// Use array destructuring to get values from the "tuple"
const [x, y, z] = getCoordinates();

In TypeScript

TypeScript supports a tuple type: [number, number, number] is a tuple of 3 numbers.
Attempting to access the 4th element of a tuple of length 3 throws a compiler error as follows.

function getCoordinates(): [number, number, number] {
  const x = 1;
  const y = 2;
  const z = 3;

  return [x, y, z];
}

// tuple.ts:10:17 - error TS2493: Tuple type '[number, number, number]' of length '3' has no element at index '3'.
const [w, x, y, z] = getCoordinates();

If you need a tuple type, TypeScript can help enforce tuple behavior at compile time.

Using Proxies in JavaScript

You can use proxies to enforce tuples at runtime.
Just to recap, a tuple has 3 properties:

Only stores primitives
Has known length – accessing outside the bounds of the array throws an error
Immutable – no writes allowed

See also Array pop() in JavaScript

Here’s how you can implement a function that returns a tuple that satisfies the above constraints using proxies:

const arr = [1, 2, 3];

function Tuple(arr) {
  if (arr.find(el => !['string', 'number', 'bigint', 'boolean', 'undefined', 'symbol', 'null'].includes(typeof el))) {
    throw new Error('Tuple can only store primitives');
  }
  return new Proxy(arr, {
    get(target, prop, receiver) {
      if (isNaN(prop)) {
        return undefined;
      }
      prop = +prop;
      if (prop < 0 || prop >= arr.length) {
        throw new Error('Cannot access tuple index ' + prop);
      }
      return arr[prop];
    },
    set() {
      throw new Error('Cannot modify tuple');
    }
  });
}

const tuple = Tuple([1, 2, 3]);

tuple[0];
tuple[4]; // Error: Cannot access tuple index 4
tuple.push(4); // TypeError: tuple.push is not a function

Unfortunately, there is no way to make two tuples === each other in JavaScript.
Objects are always compared by reference in JavaScript.

JavaScript Fundamentals for Implementing Tuples in JavaScript

JavaScript is a programming language that is used to create interactive web pages. It is a client-side scripting language, which means that it runs on the user’s browser. JavaScript can be used to add animation, interactivity, and functionality to web pages.

Here are some of the fundamentals of JavaScript:

Variables: Variables are used to store data. They are declared using the var keyword.
Data types: JavaScript has a variety of data types, including strings, numbers, booleans, objects, and arrays.
Operators: Operators are used to perform operations on data.
Control flow statements: Control flow statements allow you to control the order in which your code is executed.
Functions: Functions are blocks of code that can be reused.
Objects: Objects are used to store data in key-value pairs.
Arrays: Arrays are used to store data in a sequential order.
Events and event handlers: Events are notifications that are sent by the browser when something happens, such as when the user clicks on an element or moves the mouse over an element. Event handlers are functions that are called in response to an event.
DOM manipulation: The Document Object Model (DOM) is a tree-like structure that represents the elements of a web page. JavaScript can be used to manipulate the DOM to change the appearance or behavior of a web page.

These are just some of the fundamentals of JavaScript. There are many other concepts that you can learn as you continue to develop your skills.

Here are some resources that you can use to learn more about JavaScript:

Mozilla Developer Network (MDN): The MDN is a great resource for learning about JavaScript. It has a comprehensive reference guide, tutorials, and articles on a wide range of topics.
W3Schools: W3Schools is another great resource for learning about JavaScript. It has interactive tutorials and quizzes that can help you learn the basics of the language.
JavaScript.info: JavaScript.info is a website that provides in-depth tutorials on JavaScript. It also has a forum where you can ask questions and get help from other JavaScript developers.