Some JavaScript Shorthand Practices

Hey guys, In this article I would like to put some "line savers" and "time savers" basically JavaScript shorthand techniques that I think will be handy for many developers.

1. Short-circuit Evaluation

Checking a variable's value is bit common. lets see how we can save some lines and assign value to other variable

if (user !== null || user !== undefined || user !== '') 
{ 
profile = user 
} else 
{
profile = "some default name"
}

line saver

let profile = user || 'some default name';

2. Declaring variables

we need to declare multiple variable one after other even though we know that javascript uses hoist to your variable declaration.

let user;
let org;
let age = 25;

line saver:

let user, org, age = 25;

3. String into a Number

built in methods like parseInt and parseFloat can be used to convert string into number but can also be done by simply providing an unary operator (+) in front of string value.

let aNumerical = parseInt('764');  
let bNumerical = parseFloat('29.3');  

time saver

let aNumerical  = +'764';  
let bNumerical  = +'29.3';

4. Decimal base exponents

sometimes we need to write long values containing many zerooooooos. Instead we can use this saver

for (let i = 0; i < 10000; i++) {
...
}

time saver

for (let i = 0; i < 1e4; i++) {
...
}

5. Swap two variables

For swapping two variables, we often use a third variable. But it can be done easily and saves line with array de-structuring assignment.

let x = 'Hello', y = 'JS';   
const temp = x;  
x = y;  
y = temp;  

line saver

[x, y] = [y, x];

6. Merging of arrays:

spread operator solves many of the long hands one of them is merging two arrays, lets see how it saves us some lines:

let arrayBefore = [2, 3];  
let arrayAfter = arrayBefore.concat([6, 8]);  

// Output: [2, 3, 6, 8]

saver

let arrayAfter  = [...arrayBefore , 6, 8];  

// Output: [2, 3, 6, 8]

7. charAt()

This is straighforward

“SomeString”.charAt(0); //S

line saver

“SomeString”[0]  //S

8 For Loop

we often use for loops to iterate, lets see the better way out

const countries = [“USA”, “Japan”, “India”]
for (let i = 0; i < countries.length; i++) {
  ...
}

line saver

for (let country of countries) {
  ...
}

9 The Ternary Operator

This is a great replacement for basic if...else condition
lets see how it save us some lines

const age = 25;
let allow;

if (age  > 20) {
    allow = true;
} else {
    allow =  false;
}

line saver

let allow = age > 20 ? true : false; 

10. Arrow Function

Now this one is most important, JavaScript Arrow functions were introduced in ES6. other then having a shorter syntax it has other advantages as well. though its a separate topic to cover practice, just mentioning the basic usage

function add(a, b) {  
   return a + b;  
}  

line saver

const add = (a, b) => a + b;

I wanted to keep it short . Thank you for reading, I hope you found this helpful!