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In other languages like Python 2 and Python 3, you can define and assign values to a tuple variable, and retrieve their values like this:

tuple = ("Bob", 24)
name, age = tuple
print(name)           #name evaluates to Bob
print(age)            #age evaluates to 24

Is there anything similar in JavaScript? Or do I just have to do it the ugly way with an array:

tuple = ["Bob", 24]
name = tuple[0]       //name Evaluates to Bob
age = tuple[1]        //age Evaluates to 24

Is there a better way to simulate Python tuples in JavaScript 5?

Update: See the answer regarding ES6, which should be favored over CoffeeScript for new projects.

var name=tuple[0], age=tuple[1]; It's a bit more typing, but ugly might be an overstatement. – Brent Bradburn Sep 15, 2013 at 2:29

Javascript 1.7 added destructuring assignment which allows you to do essentially what you are after.

function getTuple(){
   return ["Bob", 24];
var [a, b] = getTuple();
// a === "bob" , b === 24 are both true
                Hmm, this is quite interesting, just ran up on this scenario myself, as JavaScript doesn't seem to provide obvious tuple support, and coming from an intense period of functional programming, you develop the want for tuples.  I also just found this, but not sure if it works, it just looked good in terms of tuple support too:  cs.umd.edu/projects/PL/arrowlets/api-tuples.xhtml.  I'll definitely look at CoffeeScript.
– 9codeMan9
                Apr 5, 2013 at 0:18
                would be great to update this answer, lots of CoffeeScript ideas have been already port to javascript, no need anymore for CoffeeScript
– ncubica
                Jun 17, 2021 at 20:38
                I won't downvote but technically this is incorrect. You can still change (ie mutate) the values of tuple.name and tuple.age after the object is declared. By definition immutable types can non be changed after they're defined. They're like read-only types where both the parameters and their values can only be declared once.
– Evan Plaice
                Apr 28, 2014 at 21:43
                @EvanPlaice if mutability is an issue, you could use Object.freeze(), i.e.: tuple = Object.freeze({ name:'Bob', age:14 })
– canon
                May 7, 2014 at 16:46
                @canon I agree, that's probably the only acceptable/correct approach in this whole thread. Unfortunately, mcm's answer doesn't freeze the object so it's still mutable.
– Evan Plaice
                May 8, 2014 at 9:24
                @EvanPlaice I don't see where the issue of mutability came from - tuples aren't immutable in the original Python example!
– Daniel Buckmaster
                Mar 11, 2015 at 20:42
                @DanielBuckmaster The difference between a list and a tuple in Python is, a list is mutable whereas a tuple is not. See docs.python.org/2/tutorial/…. Tuples aren't natively supported in JavaScript because all JS data structures are mutable unless you call Object.freeze() on the object after creation.
– Evan Plaice
                Mar 11, 2015 at 22:02

This "tuple" feature it is called destructuring in EcmaScript2015 and is soon to be supported by up to date browsers. For the time being, only Firefox and Chrome support it.

But hey, you can use a transpiler.

The code would look as nice as python:

let tuple = ["Bob", 24]
let [name, age] = tuple
console.log(name)
console.log(age)
                To future readers: this feature is supported in chrome since chrome 49 (according to the Mozilla docs). You can also check compatibility using the Mozilla docs here: developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…
– Jamie
                Apr 3, 2016 at 12:45

A frozen array behaves identically to a python tuple:

const tuple = Object.freeze(["Bob", 24]);
let [name, age]; = tuple
console.debug(name); // "Bob"
console.debug(age); // 24

Be fancy and define a class

class Tuple extends Array { 
  constructor(...items) { 
    super(...items); 
    Object.freeze(this);
let tuple = new Tuple("Jim", 35);
let [name, age] = tuple;
console.debug(name); // Jim
console.debug(age); // 35
tuple = ["Bob", 24]; // no effect 
console.debug(name); // Jim
console.debug(age); // 25

Works today in all the latest browsers.

No. The const is not reassignable. You can't do const tuple = ["Jim", 35]; tuple = ["James", 35]. You can do const tuple = ["Jim", 35]; tuple[0] = "James"; Therefore it is not immutable. – Matthew James Davis Oct 12, 2018 at 1:49

Tuples aren't supported in JavaScript

If you're looking for an immutable list, Object.freeze() can be used to make an array immutable.

The Object.freeze() method freezes an object: that is, prevents new properties from being added to it; prevents existing properties from being removed; and prevents existing properties, or their enumerability, configurability, or writability, from being changed. In essence the object is made effectively immutable. The method returns the object being frozen.

Source: Mozilla Developer Network - Object.freeze()

Assign an array as usual but lock it using 'Object.freeze()

> tuple = Object.freeze(['Bob', 24]);
[ 'Bob', 24 ]

Use the values as you would a regular array (python multi-assignment is not supported)

> name = tuple[0]
'Bob'
> age = tuple[1]

Attempt to assign a new value

> tuple[0] = 'Steve'
'Steve'

But the value is not changed

> console.log(tuple)
[ 'Bob', 24 ]
                On a side-note hopefully Tuples will get first-class support in ES6. True native tuple (ie heterogenous sequence) will also improve speed.
– Evan Plaice
                Mar 11, 2015 at 22:39

This is not intended to be actually used in real life, just an interesting exercise. See Why is using the JavaScript eval function a bad idea? for details.

This is the closest you can get without resorting to vendor-specific extensions:

myArray = [1,2,3];
eval(set('a,b,c = myArray'));

Helper function:

function set(code) {
    var vars=code.split('=')[0].trim().split(',');
    var array=code.split('=')[1].trim();
    return 'var '+vars.map(function(x,i){return x+'='+array+'['+i+']'}).join(',');

Proof that it works in arbitrary scope:

(function(){
    myArray = [4,5,6];
    eval(set('x,y,z = myArray'));
    console.log(y);  // prints 5

eval is not supported in Safari.

As an update to The Minister's answer, you can now do this with es2015:

function Tuple(...args) {
  args.forEach((val, idx) => 
    Object.defineProperty(this, "item"+idx, { get: () => val })
var t = new Tuple("a", 123)
console.log(t.item0) // "a"
t.item0 = "b"
console.log(t.item0) // "a"

https://jsbin.com/fubaluwimo/edit?js,console

There is no reason why you couldn't do this before ES2015... Also this does not answer the OP's question, he asked for destructuring – assembly_wizard Nov 20, 2016 at 16:40
const Tuple = (...args) => {
  const Tuple = f => f(...args);
  return Object.freeze(Object.assign(Tuple, args));
const get1 = tx => tx((x, y) => x);
const get2 = tx => tx((x, y) => y);
const bimap = f => g => tx => tx((x, y) => Tuple(f(x), g(y)));
const toArray = tx => tx((...args) => args);
// aux functions
const inc = x => x + 1;
const toUpperCase = x => x.toUpperCase();
// mock data
const pair = Tuple(1, "a");
// application
console.assert(get1(pair) === 1);
console.assert(get2(pair) === "a");
const {0:x, 1:y} = pair;
console.log(x, y); // 1 a
console.log(toArray(bimap(inc) (toUpperCase) (pair))); // [2, "A"]
const map = new Map([Tuple(1, "a"), Tuple(2, "b")]);
console.log(map.get(1), map.get(2)); // a b

Please note that Tuple isn't used as a normal constructor. The solution doesn't rely on the prototype system at all, but solely on higher order functions.

What are the advantages of tuples over Arrays used like tuples? Church encoded tuples are immutable by design and thus prevent side effects caused by mutations. This helps to build more robust applications. Additionally, it is easier to reason about code that distinguishes between Arrays as a collection type (e.g. [a]) and tuples as related data of various types (e.g. (a, b)).

var item2 = Item2; Object.defineProperty(this, "Item1", { get: function() { return item1 } Object.defineProperty(this, "Item2", { get: function() { return item2 } return Tuple; })(); var tuple = new Tuple("Bob", 25); // Instantiation of a new Tuple var name = tuple.Item1; // Assignment. name will be "Bob" tuple.Item1 = "Kirk"; // Will not set it. It's immutable.

This is a 2-tuple, however, you could modify my example to support 3,4,5,6 etc. tuples.

The tuple instance is still mutable, so it's technically not a tuple. For proof change tuple.Item1 = "Steve" then console.log() the output. – Evan Plaice Mar 11, 2015 at 22:35

I made a tuple implementation that works quite well. This solution allows for array destructuring, as well as basic type-cheking.

const Tuple = (function() {
    function Tuple() {
        // Tuple needs at least one element
        if (arguments.length < 1) {
            throw new Error('Tuple needs at least one element');
        const args = { ...arguments };
        // Define a length property (equal to the number of arguments provided)
        Object.defineProperty(this, 'length', {
            value: arguments.length,
            writable: false
        // Assign values to enumerable properties
        for (let i in args) {
            Object.defineProperty(this, i, {
                enumerable: true,
                get() {
                    return args[+i];
                // Checking if the type of the provided value matches that of the existing value
                set(value) {
                    if (typeof value !== typeof args[+i]) {
                        throw new Error('Cannot assign ' + typeof value + ' on ' + typeof args[+i]);
                    args[+i] = value;
        // Implementing iteration with Symbol.iterator (allows for array destructuring as well for...of loops)
        this[Symbol.iterator] = function() {
            const tuple = this;
            return {
                current: 0,
                last: tuple.length - 1,
                next() {
                    if (this.current <= this.last) {
                        let val = { done: false, value: tuple[this.current] };
                        this.current++;
                        return val;
                    } else {
                        return { done: true };
        // Sealing the object to make sure no more values can be added to tuple
        Object.seal(this);
    // check if provided object is a tuple
    Tuple.isTuple = function(obj) {
        return obj instanceof Tuple;
    // Misc. for making the tuple more readable when printing to the console
    Tuple.prototype.toString = function() {
        const copyThis = { ...this };
        const values = Object.values(copyThis);
        return `(${values.join(', ')})`;
    // conctat two instances of Tuple
    Tuple.concat = function(obj1, obj2) {
        if (!Tuple.isTuple(obj1) || !Tuple.isTuple(obj2)) {
            throw new Error('Cannot concat Tuple with ' + typeof (obj1 || obj2));
        const obj1Copy = { ...obj1 };
        const obj2Copy = { ...obj2 };
        const obj1Items = Object.values(obj1Copy);
        const obj2Items = Object.values(obj2Copy);
        return new Tuple(...obj1Items, ...obj2Items);
    return Tuple;
})();
const SNAKE_COLOR = new Tuple(0, 220, 10);
const [red, green, blue] = SNAKE_COLOR;
console.log(green); // => 220
        

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