forked from bloominstituteoftechnology/JavaScript-II
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathclosure.js
More file actions
52 lines (41 loc) · 1.4 KB
/
closure.js
File metadata and controls
52 lines (41 loc) · 1.4 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
// ==== Challenge 1: Write your own closure ====
// Write a simple closure of your own creation. Keep it simple!
// ==== Challenge 2: Create a counter function ====
const counter = () => {
// Return a function that when invoked increments and returns a counter variable.
let counter = 0;
return () => console.log(++counter);
};
// Example usage: const newCounter = counter();
// newCounter(); // 1
// newCounter(); // 2
const newCounter = counter();
newCounter();
newCounter();
newCounter();
/* STRETCH PROBLEM, Do not attempt until you have completed all previous tasks for today's project files */
// ==== 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 counter = 0;
return {
increment: function() {
console.log(++counter);
},
decrement: function() {
console.log(--counter);
}
}
};
console.log("\n");
const newerCounter = counterFactory();
for (let i = 0; i < 10; i++)
newerCounter.increment();
for (let i = 0; i < 3; i++)
newerCounter.decrement();
for (let i = 0; i < 3; i++)
newerCounter.increment();
for (let i = 0; i < 10; i++)
newerCounter.decrement();