• function that creates instances of objects!
• comparison classes vs factory functions (ff)
  • classes use constructor() function and new keyword for instantiation.
  • classes use this keyword to reference fields, while ff have local scope of all variables defined insied them.
  • classes can inherit from other classes (more complex structures possible)
  • factoryFunctions are encapsuled -> you can define what you export with Object.freeze({method1, method2}) (not sure how that works). See this blogpost

const createAnimal = (name, age, sound) => {
  return {
    name: name,
    age: age,
    makeSound () {
      console.log(sound);
    }
  }
}

const cat = createAnimal('whiskers', 2, 'miau');
cat.makeSound();

const dog = createAnimal('Honigkuchen', 5, 'wuff');
dog.makeSound();

function createAnimal(name, age, sound){
    var name = name;
    var age = age;
    function makeSound(){
        console.log(sound); 
    }
    return Object.freeze({  // export object
        makeSound           // only export function makeSoun, no fields!
    });
}

const createAnimal = (name, age) => {
  return {
    name,
    age
  }
}