JS Bin// source http://jsbin.com/diqumox

jsbin.diqumox.js

/** Rest and Spread Operators */
// Example #1 Rest Operator
function adddNumbers(...numbers) {
  return numbers.reduce((sum, number) => {
    return sum + number;
  }, 0)
}

const totalNumbers = adddNumbers(1,2,3,4,5,6,7);
console.log(totalNumbers);

// Example #2 Spread Operator
const defaultColors = ['red', 'green'];
const userFavoriteColors = ['orange', 'yellow'];
const fallColors = ['fire red', 'fall orange']
const mergeColors = ['blue', 'pink', ...fallColors, ...defaultColors, ...userFavoriteColors];
console.log(mergeColors);

// Ezample #3 Rest and Spread Operator
function validateShoppingList(...items) {
  if(items.indexOf('milk') < 0) {
    return ['milk', ...items]
  }

  return items;
}

const shoppingList = validateShoppingList('oranges', 'bread', 'eggs')
console.log(shoppingList);

// Example #4 Rest Operator
const MathLibrary = {
  calculateProduct(...rest){
    console.log('Please us the multiply method instead')
    return this.multiply(...rest);
  },
  multiply(a,b){
    return a * b;
  }
};

const mathLibraryResult = MathLibrary.calculateProduct(8, 15);
console.log(mathLibraryResult);