An huwa oġġett b'metodu li jirritorna . Oġġett huwa jekk ikollu metodu — dak li jagħmilha u spread jaħdmu. A () huwa mod konvenjenti biex toħloq iterators li jistgħu b'.
An huwa oġġett b'metodu li jirritorna . Oġġett huwa jekk ikollu metodu — dak li jagħmilha u spread jaħdmu. A () huwa mod konvenjenti biex toħloq iterators li jistgħu b'.
next(){ value, done }[Symbol.iterator]for...offunction*yieldfunction* idGenerator() {
let id = 1;
while (true) { // infinite, but lazy — only computes on demand
yield id++; // pause here, return a value, resume on next()
}
}
const gen = idGenerator();
gen.next().value; // 1
gen.next().value; // 2 — execution resumed where it paused
L-idea ewlenija: l-esekuzzjoni toqqof f'kull yield u tibda mill-ġdid fuq in-next .next(), preserving l-istat lokali bejn it-tluq. M'hemmx ħaġa li tiġi kkalkulata sakemm ma titlobx.
// process a huge/infinite sequence without building it all in memory
function* take(iterable, n) {
let i = 0;
for (const x of iterable) {
if (i++ >= n) return;
yield x;
}
}
[...take(idGenerator(), 3)]; // [1, 2, 3] — from an infinite generator
const range = {
from: 1, to: 3,
*[Symbol.iterator]() { for (let i = this.from; i <= this.to; i++) yield i; },
};
[...range]; // [1, 2, 3] — works with for...of and spread
Generators jippermetti sequenzi late/infiniti, iterazzjoni customizzata, u streaming effiċjenti fil-memoria.
Huma kienu wkoll il-bazi ta' libreriji async bikrija (co) u jinsabu taħt il-iterazzjoni async (for await...of).
Il-protokoll iterator huwa dak li jagħmilha for...of, spread, u destructuring united madwar arrays, Maps, Sets, u strings.