为什么是“你好，世界！” JavaScript 代码片段被识别为可接受的程序指令？
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Why is this "Hello, World!" JavaScript code fragment recognized as an acceptable program instruction?
提问by devaerial
Recently a coworker showed this fragment of JavaScript code:
最近一位同事展示了这段 JavaScript 代码：
greet = "?".toString.bind("hello world!")
If you paste this inside the Developer Console and execute it will print a "Hello, World!" message:
如果您将其粘贴到开发者控制台中并执行，它将打印“Hello, World！” 信息：
>> console.log(greet())
hello, world!
Another interesting thing I found is that if you paste the same greetcode inside Node.js REPL it will automatically transpile it to a "readable" format.
我发现的另一个有趣的事情是，如果您将相同的greet代码粘贴到Node.js REPL 中，它会自动将其转换为“可读”格式。
How does this work? Why is this behaviour possible in a browser and why does Node.js automatically format it?
这是如何运作的？为什么这种行为在浏览器中是可能的，为什么 Node.js 会自动格式化它？
回答by deceze
The actual code is:
实际代码是：
greet = "...".toString.bind("hello world!")
Where the ...in the string literal are the bytes E2 80 AE, which is the right-to-left override Unicode character, which causes everything after it to be displayed in reverse. It's used for writing right-to-left languages like Arabic or Hebrew.
其中...字符串文字中的 是 bytes E2 80 AE，它是从右到左覆盖的 Unicode 字符，这会导致其后的所有内容反向显示。它用于编写从右到左的语言，如阿拉伯语或希伯来语。
回答by feedy
You have hidden characters which reverse the text. Here you can see the raw characters: https://www.soscisurvey.de/tools/view-chars.php
您有反转文本的隐藏字符。在这里你可以看到原始字符：https: //www.soscisurvey.de/tools/view-chars.php
