radzionc

const dog = {
  age: 4,
  name: 'Ronni'
}

dog.age = 6   // OK
dog = {}      // ERROR

radzionc

function standard() {
  return 'Rock'
}

const arrowLike = () => 'Rock'

radzionc

const dog = {
  name: 'Ronni',
  age: 4,
  talk: function() {
    retun `my name is ${this.name}`
  }
}

// if you have some variables around
const name = 'Ronni'

radzionc

const data = fetch('http://something.com')
             .then(result => result.json())

radzionc

const Dog = (age, name) => ({
  age,
  name,
  talk: function() {
    ...
  }
})

radzionc

const procesData = ({ someProp, otherProp }) => {
  ...
}

radzionc

cosnt one = {
  a: 1,
  b: 2
}

const two = {
  c: 2,
  d: 3
}

radzionc

const create = (proto, props) =>
  Object.assign(Object.create(proto), props)

const Vector2D = (x, y) => create({
  }, {
    x,
    y,
    length: Math.hypot(x, y)
  }
)

radzionc

...
scaleBy (factor) {
  return Vector2D(x * factor, y * factor)
},
negate () {
  return this.scaleBy(-1)
},
normalize () {
  return this.scaleBy(1 / this.length)
}

radzionc

...
add ({ x, y }) {
  return Vector2D(this.x + x, this.y + y)
},
subtract ({ x, y }) {
  return Vector2D(this.x - x, this.y - y)
}
...