2020-06-08
1107
#vanilla javascript
Gbolahan Olagunju
19958
Jun 8, 2020 ⋅ 3 min read

How to decide between classes v. closures in JavaScript

Gbolahan Olagunju Let's have a chat about your project. Find me on Twitter @iamgbols.

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3 Replies to "How to decide between classes v. closures in JavaScript"

  1. Why aren’t you building your Closure like your class and getting the best of both worlds?

    let UserClosure = function(firstName, lastName, age, occupation) {
    this.firstName = params.firstName;
    this.lastName = params.lastName;
    this.age = age;
    this.occupation = occupation;

    let privateValue = “Can’t see this!”;
    function privateFunction(args) { // private method }
    }
    UserClosure.prototype.getAge = function() { return this.age; }
    UserClosure.prototype.describeSelf = function() { …. };

    let someOne = new UserClose(“first”, “last”, 55, “dev”);

    This isn’t intended as argumentative. I’m looking for why I should start using classes instead of the above construction in some upcoming work.

  2. Here’s how to get the best of both worlds.

    const Foo = (function() {
    //create a prototype.
    const prot = {
    bar(bas) {
    bas = bas || this.fallbackBas;
    console.log(“bar says ” + bas);
    }
    } //end of prot.

    //constructor.
    return function(fallback) {
    const o = Object.create(prot);
    //new object, prot as prototype.
    o.fallbackBas = fallback;
    return o;
    } //constructor
    })(); //iif

    const f = new Foo(“This is a fallback.”);
    f.bar(“This is not a fallback.”);
    f.bar();

    /*Output:

    bar says This is not a fallback.
    bar says This is a fallback.
    */

    All the funcs are created only once, and other vars can go in the same outer func.

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