Tips & Tricks
1. Abonden the bootstrap
https://betterprogramming.pub/3-reasons-to-abandon-bootstrap-in-2021-aa71bbc1af14
1. Conditionally Add Properties to Object
const condition = true;
const person = {
id: 1,
name: 'John Doe',
...(condition && { age: 16 }),
};
4. The Keyword in
const user = {
name: "Mehdi",
age: 19,
}
if("age" in user){
console.log("Age is available in the user object.");
}
//Age is available in the user object.
"name" in user; //true
"text" in user; //false
if("text" in user){
console.log("text is available");
}
//undefined.
5. Nullish Coalescing, ?? Operator
const foo = null ?? 'Hello';
console.log(foo); // returns 'Hello'
const bar = 'Not null' ?? 'Hello';
console.log(bar); // returns 'Not null'
const baz = 0 ?? 'Hello';
console.log(baz); // returns 0
with OR
const cannotBeZero = 0 || 5;
console.log(cannotBeZero); // returns 5
const canBeZero = 0 ?? 5;
console.log(canBeZero); // returns 0
9. Check Falsy Values in an Array
const myArray = [null, false, 'Hello', undefined, 0];
// filter falsy values
const filtered = myArray.filter(Boolean);
console.log(filtered); // returns ['Hello']
// check if at least one value is truthy
const anyTruthy = myArray.some(Boolean);
console.log(anyTruthy); // returns true
// check if all values are truthy
const allTruthy = myArray.every(Boolean);
console.log(allTruthy); // returns false
5. Dynamic properties
const dynamic = 'name'
const person = {
age: 33,
[dynamic]: 'John'
}
const dynamic = 'name'
const person = {
age: 33,
[dynamic]: 'John',
[`interpolated-${dynamic}`]: true
}
const dynamic = 'name'
let person = {
age: 33,
}
person[dynamic] = 'John'
8. Unique array values
const numbers = [1, 2, 2, 3, 3, 4, 5, 5, 6, 6, 7, 7, 7]
const unique_numbers = [...new Set(numbers)]
console.log(unique_numbers); // [1, 2, 3, 4, 5, 6, 7]