object destructuring in es6

destructuring.js

// simple destructuring without default
let obj = {bananaphone: 'hello?'};
let {bananaphone} = obj;

console.log(bananaphone); // hello?

// destructuring with default
let {missingkey = 'hey?'} = obj;
console.log(missingkey); // hey?

// destructuring in function
function destructure({missingkey = 'hey?'} = {}) {
     console.log(missingkey);   
}

destructure(obj); // hey?
destructure({missingkey: 'hello'}); // hello
destructure(); // hey?

// previous function is the same as this
function destructure(options = {}) {
     let {missingkey = 'hey?'} = options;
}

// and this (if no options object is provided)
function destructure(options) {
     let {missingkey = 'hey?'} = options || {};    
}

// destructure into a different named variable
function destructure({othername: missingkey = 'hey?'}) {
     console.log(missingkey, othername);
}

destructure({missingkey: 'exists'}); // undefined, "othername"
destructure(); // undefined, "hey?"