Javascript & Typescript Style Guide

Naming

Variable Naming

• Variable names have to be meaningful nouns.
• Variable names must be defined in camelCase format.

//bad
const date;
const yy;
const ms = 60000;
 
//good
const currentDate;
const year;
const oneMinuteInMiliseconds = 60000;

Constant Naming

• Constant names must be defined in CONSTANT_CASE format.

//bad
const maxLength = 10;
 
//good
const MAX_LENGTH = 10;

Class/Function Names

• Class names have to start with UpperCamelCase.
• Class names have to be a noun.
• Functions have to start with verb followed by a noun and be written in camelCase format.
  • get + content explanation of the function
  • set + content explanation of the function
  • reset + content explanation of the function
  • insert + content explanation of the function
  • update + content explanation of the function
  • delete + content explanation of the function
  • create + content explanation of the function
  • add + content explanation of the function
  • remove + content explanation of the function
  • send + content explanation of the function
  • init(initiate) + content explanation of the function
  • position + content explanation of the function

//Bad
const getColumns = []; //This is not a function
 
//Good
const columns = [];
 
//Good
const getColumns = () => [];

Boolean returning variables

• The variables that return a Boolean variable must start with one of the following prefixes:
  • is + content explanation of the variable
  • has + content explanation of the variable
  • does + content explanation of the variable
  • check + content explanation of the variable

// Bad
let loading;
 
// Good
let isLoading;

Loops

• Always keep a space after loop and if blocks.

for (let i = 0; i < 10; ++i) {
  // ...
}
 
while (condition) {
  // ...
}
 
if (condition) {
  // ...
}

Imports

• Use correct syntax for each exported code.

import { type UserType } from './types'; // export type UserType = { }
// or
import type { UserType } from './types'; // export type UserType = { }
 
import User from './User'; // export default function User() { }
 
import { User } from './User'; // export const User = () => { }