javascript function arguments destructuring code example

Example 1: javascript function destructuring

function f() {
  return [1, 2];
}

let a, b; 
[a, b] = f(); 
console.log(a); // 1
console.log(b); // 2

Example 2: js object destructuring with defaults

// Taken from top stack overflow answer

const { dogName = 'snickers' } = { dogName: undefined }
console.log(dogName) // what will it be? 'snickers'!

const { dogName = 'snickers' } = { dogName: null }
console.log(dogName) // what will it be? null!

const { dogName = 'snickers' } = { dogName: false }
console.log(dogName) // what will it be? false!

const { dogName = 'snickers' } = { dogName: 0 }
console.log(dogName) // what will it be? 0!

Example 3: array destructuring methods parameters

function foo([a, b]) {
   console.log(`param1: ${a}, param2: ${b}`);
}

Example 4: array destructuring methods parameters

const items = [ ['foo', 3], ['bar', 9] ];
items.forEach(([word, count]) => {
    console.log(word+' '+count);
});