Map & Set
Map
Seperti Object tapi key bisa tipe apapun.
.set(key, value).get(key).has(key).delete(key).size
Set
Koleksi nilai unik (tidak ada duplikat).
.add(value).has(value).delete(value).size
Seperti Object tapi key bisa tipe apapun.
.set(key, value).get(key).has(key).delete(key).sizeKoleksi nilai unik (tidak ada duplikat).
.add(value).has(value).delete(value).size// Map
const scores = new Map();
scores.set("Ali", 95);
scores.set("Budi", 87);
scores.set("Cici", 92);
// Set
const unique = new Set([1,2,2,3,3,3,4,5,5]);
const tags = new Set(["html","css","js","html","css"]);
const o = document.getElementById('output');
o.innerHTML =
'// Map
'+
'scores.get("Ali") → '+scores.get("Ali")+'
'+
'scores.has("Budi") → '+scores.has("Budi")+'
'+
'scores.size → '+scores.size+'
'+
'// Set (auto-removes duplicates!)
'+
'new Set([1,2,2,3,3,3,4,5,5])
→ '+JSON.stringify([...unique])+'
'+
'new Set(["html","css","js","html","css"])
→ '+JSON.stringify([...tags])+'
'+
'// Array dedup trick:
'+
'[...new Set(array)]';