Javascript ++: How to Level Up Your Code

Try to Avoid Type Constructors

Type Constructors are slower than declaring the object type as seen in the bottom three examples below. Constructors also create objects instead of primitive value so you can get some nasty side effects.

let x1 = new Object();
let x2 = new String();
let x3 = new Number();
let a1 = {};           
let a2 = "";           
let a3 = 0;            

Use Strict Equals

Abstract Equality Comparison (==)

"42" == 42
=> true

Abstract Comparators perform a type conversion when comparing so if you try to compare a string with a number, you might find yourself with a true value instead of a false one.

Strict Equality Comparison (===)

"42" === 42
=> false

Strict Comparators don’t do a type conversion so if the two objects you are comparing aren’t both integers (for example) with the same value, then you will get a false output since, well, these two objects aren’t the same thing!

Lots of Variables

I know what you’re thinking, “what!?” But passing in lots of arguments can actually benefit you. Don’t ever be afraid to add more than one, two, or even three arguments! Plus, the order of the arguments inside your function doesn’t matter, so you could even use the first variable at the very end of your function.

function sayHello(options) {
   let sentence = {
      greeting: "Good morning!",
      pleasantry: "How are you,",
      name: "buddy",
      exclamation: "?",
      question: "some coffee?"
   }
}
let name = "John"
let exclamation = "!?"
let question = "lunch?
function sayHello(, , name, question, exclamation)
=> "Good morning! How are you, John!? Do you want to grab lunch?"

Thoroughly Comment Your Code

When you’re working on a project, you can convince yourself that you will never forget what a method, function, or specific line of code does. While sometimes may be true, generally you’re going to forget what your code does and having to read back through it line by line to figure out what’s going on is awful. Just take the three extra seconds to add comments to your code and debugging, refactoring, or adding new features will be a breeze, especially if you step away from your code for a while before coming back to it.

//This code will greet a user upon login
function greeting() {
   alert("Welcome!")
}

Passing Empty Parameters

Sometimes you want to call a method but you don’t want to pass every single parameter. There’s a better way than trying to use null to fill in the blank! Use a spread operator with an array since arrays are sparse in nature and can have blank values without issue.

method(...['parameter1', , 'parameter3'])

Bonus:

• Prettier - an opinionated code formatter
• Auto Close Tag - automatically adds closing tags
• Better Comments - helps you create more human-friendly comments