Strategy Pattern JS example

strategy-pattern.js

// Example. Let's sort the apples, pears, and oranges into the right baskets.

const fruits = ["apple", "pear", "apple", "apple", "orange", "pear", "orange", "pear", "apple"]
let appleBasket = []
let pearBasket = []
let orangeBasket = []

let strategies = []

const appleSortStrategy = (fruit) => {
  if(fruit === "apple") {
    appleBasket.push(fruit)
  }
}
strategies.push(appleSortStrategy)

const pearSortStrategy = (fruit) => {
  if(fruit === "pear") {
    pearBasket.push(fruit)
  }
}
strategies.push(pearSortStrategy)

const orangeSortStrategy = (fruit) => {
  if(fruit === "orange") {
    orangeBasket.push(fruit)
  }
}
strategies.push(orangeSortStrategy)

fruits.forEach((fruit) => {
  strategies.forEach((strategy) => strategy(fruit))
})

console.log(appleBasket)  // ["apple", "apple", "apple", "apple"]
console.log(pearBasket)   // ["pear", "pear", "pear"]
console.log(orangeBasket) // ["orange", "orange"]