ES6 - Destructuring

May 7, 2019

Set variables values by object destructuring.

Destructuring first level

    const pony = { foo: 'foo test' }
    
    const { foo } = pony
    
    //foo value is equal to = pony.foo = 'foo test'

Destructuring with alias

    const pony = { foo: 'foo test with alias' }
    
    const { foo: baz }  = pony
    
    //baz value is equal to pony.foo = 'foo test with alias'

Destructuring with default value

const pony = {}

const { foo='default value' } = pony

//foo value is equal to pony.foo with 'default value' default value

Destructuring Level 2:

    const pony = {
        foo: {
            baz: 'baz'
        }        
    }

    const { foo: baz } = pony
    
    //baz value will be 'baz'

Destructuring response level 0 and nested

1. Destructuring level 0 raise undefined is the variable not does not exist
2. Destructing nested level raise an error when the variable does not exist

Destructing in function parameters

function foo(bar={a: 1, b: 2}) {
}