Destructuring Assignment

Destructuring assignment allows you to assign the properties of an array or object to variables using syntax that looks similar to array or object literals.

JavaScript developers spend a lot of time pulling data out of objects and arrays. Like

 var options = {
        repeat: true,
        save: false
    };

 // later

 var localRepeat = options.repeat,
     localSave = options.save;

With destructuring you will

 var options = {
        repeat: true,
        save: false
    };

 var { repeat: localRepeat, save: localSave } = options;
 console.log(localRepeat);       // true
 console.log(localSave);         // false

Destructuring nested objects

 var options = {
        repeat: true,
        save: false,
        rules: {
            custom: 10,
        }
    };

 var { repeat, save, rules: { custom }} = options;

 console.log(repeat);        // true
 console.log(save);          // false
 console.log(custom);        // 10

Array Destructuring

 var colors = [ "red", "green", "blue" ];

 var [ firstColor, secondColor ] = colors;

 console.log(firstColor);        // "red"
 console.log(secondColor);       // "green"