javascript - 浏览器外的生成器和 "yield"

Question

这是找到的代码片段 here ，在一篇描述 JavaScript 中的生成器和迭代器的 MDN 文章中。

function simpleGenerator(){  
  yield "first";  
  yield "second";  
  yield "third";  
  for (var i = 0; i < 3; i++)  
    yield i;  
}  

var g = simpleGenerator();  
print(g.next()); // prints "first"  
print(g.next()); // prints "second"  
print(g.next()); // prints "third"  
print(g.next()); // prints 0  
print(g.next()); // prints 1  
print(g.next()); // prints 2  
print(g.next()); // StopIteration is thrown  

上面我们读到:

The yield keyword is only available to code blocks in HTML wrapped in a

<script type="application/javascript;version=1.7">

block (or higher version).

事实上，当嵌入 HTML 文件并包含在上述标记中时，该代码片段可以正常工作。问题是，我在 Rhino 中尝试过，它似乎无法在 HTML 和浏览器之外工作。

那么如何在浏览器之外使用生成器呢？

Answer 1

https://developer.mozilla.org/en/New_in_Rhino_1.7R1#JavaScript_1.7_features

To enable JavaScript 1.7 support, you must set the version as 170 using the Context.setLanguageVersion() API call. If you are using the Rhino shell, you can specify -version 170 on the command line or call version(170) in code executed by the shell.