OOP vs FP
Let's compare how we would go about creating a Car variable which has a method to increase its mileage (number of travelled kilometers) in Object-Oriented Programming and Functional Programming.
OOP
class Car {
constructor(make, year, mileage) {
this.make = make;
this.year = year;
this.mileage = mileage;
}
increaseMileage(mileage) {
this.mileage += mileage;
}
}
var ferrari = new Car("Ferrari", 2017, 5000);
ferrari.increaseMileage(500);
console.log(ferrari);
FP
const ferrari = {
make: 'Ferrari',
year: 2017,
mileage: 5000
};
function increaseMileage(obj, mileage){
const objCopy = _.cloneDeep(obj);
objCopy.mileage += mileage;
return objCopy;
}
let ferrariWithIncreasedMileage = increaseMileage(ferrari, 500);
console.log(ferrariWithIncreasedMileage);