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// ==== Challenge 1: Write your own closure ====
// Write a simple closure of your own creation. Keep it simple!
function simpleClosure(name) {
const sayMyNameSayMyName = name;
function destinysChild() {
return sayMyNameSayMyName;
}
return destinysChild();
}
console.log(simpleClosure('Brandon'));
// ==== Challenge 2: Create a counter function ====
const counter = function() {
// Return a function that when invoked increments and returns a counter variable.
let count = 0;
function addIt() {
return count++;
}
return addIt;
};
let newCounter = counter();
console.log(newCounter(1));
console.log(newCounter(1));
console.log(newCounter(1));
// Example usage: const newCounter = counter();
// newCounter(); // 1
// newCounter(); // 2
// ==== 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 = 0;
return {
increment: () => {
return ++count;
},
decrement: () => {
return --count;
}
};
};
const foo = counterFactory();
console.log(foo.increment());
console.log(foo.increment());
console.log(foo.increment());
console.log(foo.increment());
console.log(foo.decrement());