blocks|key|723293|text|不是以标准的方式。有些浏览器是已实施+python风格的生成器，但它们需要显式激活的扩展。有人建议增加发电机开发下一个版本的ECMAScript规范，但我不认为它很快就能使用。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|723294|到目前为止，您能做的最好的就是使用旧的外部迭代器模式。它同样强大，尽管在更复杂的情况下编写是一件痛苦的事情。|723295|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en/JavaScript/Guide/Iterators_and_Generators|1|http://wiki.ecmascript.org/doku.php?id=proposals%253aiterators_and_generators|2|https://en.wikipedia.org/wiki/Iterator^0|F|3|0|1D|5|1|0|J|5|2|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@$A|S|B|T|1|U]|$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|6|7|Y|8|@]|9|@$A|Z|B|10|1|11]]|C|$]]|$1|F|3|-4|5|6|7|12|8|@]|9|@]|C|$]]]|G|$H|$5|I|J|K|C|$L|M]]|N|$5|I|J|K|C|$L|O]]|P|$5|I|J|K|C|$L|Q]]]]

Not in a standard way. Some browsers <a href="https://developer.mozilla.org/en/JavaScript/Guide/Iterators_and_Generators" rel="nofollow">already implement</a> python-style generators, but they require extensions that need to be explicitly activated.
There are proposals to <a href="http://wiki.ecmascript.org/doku.php?id=proposals%3aiterators_and_generators" rel="nofollow">add generators</a> to a next version of the ECMAScript spec, but I wouldn't see that being useable very soon.

So far, the best you can do is to use the old school <a href="https://en.wikipedia.org/wiki/Iterator" rel="nofollow">external iterator</a> pattern. It is just as powerful, although it is a pain to write in more complicated cases.

blocks|key|1462848|text|这并不是非常实用，但您可以实现如下相同的基本效果：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1462849|function+make_generator(start,+end)+{
++var+i=start;
++return+function()+{
++++if+(i<end)+{
++++++output+=+i;
++++++i+%2B=+1;
++++++return+output;
++++}
++++else+{
++++++return+null;
++++}
++}
}
var+out+=+document.getElementById('out');
var+generator+=+make_generator(1,10);
var+g+=+generator();
while+(g)+{
++if+(out.innerHTML)
++++out.innerHTML+=+out.innerHTML+%2B+' '+%2B+g;
++else
++++out.innerHTML+=+g;
++g+=+generator();
}|code-block|syntax|javascript|1462850|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

It's not super practical, but you can achieve the same basic effect like this:

<pre><code>function make_generator(start, end) {
 var i=start;
 return function() {
 if (i&lt;end) {
 output = i;
 i += 1;
 return output;
 }
 else {
 return null;
 }
 }
}
var out = document.getElementById('out');
var generator = make_generator(1,10);
var g = generator();
while (g) {
 if (out.innerHTML)
 out.innerHTML = out.innerHTML + '&lt;br&gt;' + g;
 else
 out.innerHTML = g;
 g = generator();
}
</code></pre>

blocks|key|1462844|text|在JavaScript+1.7中：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1462845|function+rangeGen(n)+{
++++for+(let+i+=+0;+i+<+n;+i%2B%2B)
++++++++yield+i;
}|code-block|syntax|javascript|1462846|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

In JavaScript 1.7:

<pre><code>function rangeGen(n) {
 for (let i = 0; i &lt; n; i++)
 yield i;
}
</code></pre>

blocks|key|1462889|text|您可以使用yield关键字。您可以阅读更多关于it的这里+(MDN)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1462890|pause关键字用于暂停并恢复生成器函数。|blockquote|1462891|function*+range(n)+{
++++for+(let+i+=+0;+i+<+n;+i%2B%2B)+{
++++++++yield+i;
++++}
}

const+generator+=+range(10);

console.log(generator.next());++//+{+value:+0,+done:+false+}
console.log(generator.next());++//+{+value:+1,+done:+false+}
...
console.log(generator.next());++//+{+value:+9,+done:+false+}
console.log(generator.next());++//+{+value:+undefined,+done:+true+}|code-block|syntax|javascript|1462892|注意在*关键字之后的function。|1462893|现在被广泛支持：犬科，MDN|1462894|TypeScript符号：|1462895|function*+range(n:+number):+IterableIterator<number>+{
++++for+(let+i+=+0;+i+<+n;+i%2B%2B)+{
++++++++yield+i;
++++}
}|1462896|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/yield|1|https://caniuse.com/es6-generators|2|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/yield#browser_compatibility^0|5|5|Q|2|0|0|0|0|3|1|A|8|0|8|2|1|B|3|2|0|0|0^^$0|@$1|2|3|4|5|6|7|17|8|@$9|18|A|19|B|C]]|D|@$9|1A|A|1B|1|1C]]|E|$]]|$1|F|3|G|5|H|7|1D|8|@]|D|@]|E|$]]|$1|I|3|J|5|K|7|1E|8|@]|D|@]|E|$L|M]]|$1|N|3|O|5|6|7|1F|8|@$9|1G|A|1H|B|C]|$9|1I|A|1J|B|C]]|D|@]|E|$]]|$1|P|3|Q|5|6|7|1K|8|@]|D|@$9|1L|A|1M|1|1N]|$9|1O|A|1P|1|1Q]]|E|$]]|$1|R|3|S|5|6|7|1R|8|@]|D|@]|E|$]]|$1|T|3|U|5|K|7|1S|8|@]|D|@]|E|$L|M]]|$1|V|3|-4|5|6|7|1T|8|@]|D|@]|E|$]]]|W|$X|$5|Y|Z|10|E|$11|12]]|13|$5|Y|Z|10|E|$11|14]]|15|$5|Y|Z|10|E|$11|16]]]]

You can use the <code>yield</code> keyword. You can read more about it <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/yield" rel="nofollow noreferrer">here</a> (MDN).
<blockquote>
The yield keyword is used to pause and resume a generator function
</blockquote>
<pre class="lang-js prettyprint-override"><code>function* range(n) {
 for (let i = 0; i &lt; n; i++) {
 yield i;
 }
}

const generator = range(10);

console.log(generator.next()); // { value: 0, done: false }
console.log(generator.next()); // { value: 1, done: false }
...
console.log(generator.next()); // { value: 9, done: false }
console.log(generator.next()); // { value: undefined, done: true }
</code></pre>
Notice the <code>*</code> after the <code>function</code> keyword.
It's widely supported now: <a href="https://caniuse.com/es6-generators" rel="nofollow noreferrer">caniuse</a>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/yield#browser_compatibility" rel="nofollow noreferrer">MDN</a>
<hr />
TypeScript notation:
<pre><code>function* range(n: number): IterableIterator&lt;number&gt; {
 for (let i = 0; i &lt; n; i++) {
 yield i;
 }
}
</code></pre>

Is there any "python's Generator" equivalent in JavaScript? 

PS:
Python's Generator is very memory efficient when we need to do one time iterate through a big array, hash... 
"Generators are iterables, but you can only read them once. It's because they do not store all the values in memory, they generate the values on the fly"

(Python's Generator explained in this thread: <a href="https://stackoverflow.com/questions/231767/the-python-yield-keyword-explained">What does the &quot;yield&quot; keyword do in Python?</a> )

JavaScript: Is there any "python's Generator" equivalent in JavaScript?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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在JavaScript中有任何类似的“python生成器”吗？当我们需要做一次时，迭代一个大的数组，哈希.生成器是可迭代的，但是只能读取一次__。这是因为它们没有将所有值存储在内存中，而是动态地生成__值(Python的生成器在以下线程中解释： )

问JavaScript:在JavaScript中有类似的“python生成器”吗？
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