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Javascript Generator Functions

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By your_full_name
1 min read
Javascript Generator Functions

Ref: [function](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/function)

function* 宣告 generator function。呼叫它不會執行內容，而是回傳一個 generator 物件；每次 next() 執行到下一個 yield 就暫停。

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function* idGenerator() {
  let id = 1;
  while (true) {
    yield id++;
  }
}

const gen = idGenerator();
gen.next().value; // 1
gen.next().value; // 2
  • next() 回傳 { value, done }。
  • 執行完（或 return）之後 done 才會是 true，上面的無限迴圈寫法永遠不會 done。
javascript
javascript
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