Introduction

Destructuring is a pattern matching technique that is added to Javascript recently in EcmaScript 6.

It allows you to bind a group of variables to a corresponding set of values when their pattern matches to the right hand-side and the left hand-side of the expression.

Syntax

• let [x, y] = [1, 2]
• let [first, …rest] = [1, 2, 3, 4]
• let [one, , three] = [1, 2, 3]
• let [val=‘default value’] = []
• let {a, b} = {a: x, b: y}
• let {a: {c}} = {a: {c: ‘nested’}, b: y}
• let {b=‘default value’} = {a: 0}

Remarks

Destructuring is new in the ECMAScript 6 (A.K.A ES2015) specification and browser support may be limited. The following table gives an overview of the earliest version of browsers that supported >75% of the specification.

Destructuring Objects

Destructuring function arguments

Nested destructuring

Destructuring arrays

Destructuring inside variables

Default value while destructuring