javascript_typescript_styleguide.md

Javascript/Typescript Style Guide

This style guide is inspired from the john papa style guide.

Small Functions

Pro :

• Easy to :
  • Test
  • Read
  • Reuse
  • Maintain

Naming

Variables

Boolean

// IS
isLoading, isActive, isLogged, isSet, isVisible, isFinished, isFound, isOpen
// HAS
hasError, hasLicense, hasCar
// CAN
canEvaluate, canEdit, canRead

Number Of

numberOfUsers, numberOfCars, numberOfItems, numberOfMessages, numberOfTickets

Function

Computed

cars.computeTotalPrice();

Complement name

get/set, add/remove, create/destroy, start/stop, insert/delete, increment/decrement, old/new, begin/end, first/last, up/down, min/max, next/previous, old/new, open/close, show/hide, suspend/resume, etc.

Named Functions instead Anonymous Function

Pro Named Function :

• Easy to :
  • Test
  • Reuse

Examples

// Avoid
myArray.filter((value) => {
   return item > 0 ? true : false;
});

// Recommanded
// + Test separately isPositive function
// + Reuse isPositive
// + Easier to read myFunc(isPositive);
const isPositive = (value) => {
   return item > 0 ? true : false;
};

myArray.filter(isPositive);

Sources

• Coding like Shakespeare
• AngularJS - Style Guide
• Data Structures Algorithms
• Clean code typescript