Javascript part1
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This document provides JavaScript style guidelines for objects, functions, and other best practices. For objects, it recommends using object literal syntax, computed property names, and property shorthand. For functions, it suggests using named function expressions over declarations, wrapping IIFEs in parentheses, and avoiding naming parameters "arguments." It also offers tips for default parameter syntax and declaring functions.
![“ Use computed
property names
when creating
objects with
dynamic property
names.
// good
const obj = {
id: 5,
name: 'San Francisco',
[getKey('enabled')]: true,
};](https://image.slidesharecdn.com/javascript-part1-170325202121/85/Javascript-part1-5-320.jpg)
Javascript part1
- 1. Style guide javascript and best practices Part 1
- 2. How i am ? Belgacem Ben Ltaif Full stack developer & Front End Technical Lead Founder & Cto Powerful Consulting twitter @gasston_egass github @gasston Email : belgacem.benltaif@gmail.com
- 3. Objects 1.
- 4. “ Use the literal syntax for object creation. // bad const item = new Object(); // good const item = {};
- 5. “ Use computed property names when creating objects with dynamic property names. // good const obj = { id: 5, name: 'San Francisco', [getKey('enabled')]: true, };
- 6. “ Use property value shorthand. const foo = 'Luke'; // bad const obj = {foo: foo,}; // good const obj = {foo};
- 7. “ Only quote properties that are invalid identifiers // bad const bad = {'foo': 3, 'bar': 4,'data-blah': 5,}; // good const good = { foo: 3, bar: 4, 'data-blah': 5, };
- 8. “Do not call Object.prototype methods directly, such as hasOwnProperty, proumerable, and isPrototyppertyIsEneOf.
- 9. “// bad console.log(object.hasOwnProperty(key)); // good console.log(Object.prototype.hasOwnProperty.call(object, key)); // best const has = Object.prototype.hasOwnProperty; // cache the lookup once, in module scope. /* or */ import has from 'has'; // ... console.log(has.call(object, key));
- 10. Functions 2.
- 11. “Use named function expressions instead of function declarations. // bad function foo() { } const foo = function () { // ... }; // good const foo = function bar() { // ... };
- 12. “ Wrap immediately invoked function expressions in parentheses // immediately-invoked function expression (IIFE) (function () { console.log('Welcome to the Internet. Please follow me.'); }());
- 13. “ Never name a parameter arguments. This will take precedence over the arguments object that is given to every function scope. // bad function foo(name, options, arguments) { // ... } // good function foo(name, options, args) { // ... }
- 14. “Use default parameter syntax rather than mutating function arguments. // really bad function handleThings(opts) { opts = opts || {}; // ... } function handleThings(opts) { if (opts === void 0) { opts = {}; } // good function handleThings(opts = {}) { // ... }
- 15. Worning !! Never declare a function in a non-function block (if, while, etc). Assign the function to a variable instead. Browsers will allow you to do it, but they all interpret it differently, which is bad news bears.
- 16. thanks! Any questions? twitter @gasston_egass github @gasston Email : belgacem.benltaif@gmail.com