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// ==== Challenge 1: Write your own closure ====
// Write a simple closure of your own creation. Keep it simple!
//objective: create a function that oscilates the speed of an action
function repeat(n, action) {
for (let i = 0; i < n; i++) {
action(i);
}
}
function increase(wait) {
base = 2;
return action => {
setInterval(timeIt, wait);
function timeIt() {
base = action(base);
console.log(base);
}
};
}
let base2 = increase(1000);
//base2(x => x * 2);
/* STRETCH PROBLEMS, Do not attempt until you have completed all previous tasks for today's project files */
// ==== Challenge 2: Create a counter function ====
const counter = () => {
// Return a function that when invoked increments and returns a counter variable.
let count = 1;
return () => {
return count++;
};
};
// Example usage: const newCounter = counter();
// newCounter(); // 1
// newCounter(); // 2
let newCounter = counter();
console.log(newCounter());
console.log(newCounter());
console.log(newCounter());
// ==== Challenge 3: Create a counter function with an object that can increment and decrement ====
const counterFactory = () => {
// Return an object that has two methods called `increment` and `decrement`.
// `increment` should increment a counter variable in closure scope and return it.
// `decrement` should decrement the counter variable and return it.
let count = 1;
let factory = {
increment() {
return count++;
},
decrement() {
return count--;
},
};
return factory;
};
let newFactory = counterFactory();
console.log(newFactory.increment());
console.log(newFactory.increment());
console.log(newFactory.increment());
console.log(newFactory.increment());
console.log(newFactory.increment());
console.log(newFactory.increment());
console.log(newFactory.increment());
console.log(newFactory.increment());
console.log(newFactory.increment());
console.log(newFactory.decrement());
console.log(newFactory.decrement());
console.log(newFactory.decrement());
console.log(newFactory.decrement());
console.log(newFactory.decrement());
console.log(newFactory.decrement());