JS
What’s new in JavaScript
ES2023
Gaute Meek Olsen
JS
What’s new in JavaScript
ES2023
1
Gaute Meek Olsen
2
Stages
- 0
- 1
- 2
- 3
- 4
3
findLast
const array = [1, 2, 3, 4, 5]
const even = array.find((n) => n % 2 === 0)
console.log(even)
4
findLastIndex
function findLastIndex(array, predicate) {
let l = array.length;
while (l--) {
if (predicate(array[l], l, array))
return l;
}
return -1;
}
const array = [1, 2, 3, 4, 5]
console.log(findLastIndex(array, (n) => n % 2 === 0))
5
toReversed
const array = [3, 2, 1]
const reversed = array.reverse()
console.log(array)
console.log(reversed)
6
toSorted
const array = [3, 2, 1]
const sorted = array.sort((a, b) => a - b)
console.log(sorted)
7
toSpliced
const array = ['🍎', '🥝', '🍊']
const myFruit = array.splice(0, 1, '🥦')
console.log(array)
console.log(myFruit)
8
with
const array = ['a', 'b', 'd']
9
Symboler i WeakMap, WeakSet og WeakRef
const symbol = Symbol('my-symbol')
const symbol2 = Symbol('my-symbol')
console.log(symbol === symbol2)
const cache = new WeakMap()
const key = {}
cache.set(key, 'hello')
console.log(cache.get(key))
10
Hashbang
#!/usr/bin/env node
console.log('👋')
11
12
Takk for meg!
13