通过名称调用函数 [英] Calling a function by its name

问题描述

有时我们需要通过名称来调用函数。我可以用普通的JavaScript实现如下：

Sometimes we need to call a function by its name. I can do it in plain JavaScript as below:

global=this
function add(a,b){return a+b}
global['add'](1,2)

哪个有效正如预期的那样， add（）被调用。

Which works as expected and add() gets called.

等效的CoffeeScript代码可以写成如下。

Equivalent CoffeeScript code might can be written as below.

global=@
add=(a,b)->a+b
global['add'](1,2)

编译为JavaScript：

which compiles to JavaScript as:

(function() {
  var add, global;
  global = this;
  add = function(a, b) {
    return a + b;
  };
  global['add'](1, 2);
}).call(this);

......它不起作用。

...and it doesn't work.

Microsoft JScript runtime error: Object doesn't support this property or method

这个问题有一个简单的解决方案吗？

Is there an easy solution to this problem?

注意：

1. 我没有在浏览器中运行代码，因此没有窗口对象。但是在普通JS中，我总是可以通过分配 global = this 来捕获全局范围，然后从中获取函数指针。

1. I am not running the code in a browser therefore there is no window object. But in plain JS I can always capture the global scope by assigning global=this and then get the function pointer from it.

我发现CoffeeScript中的一个解决方案是将所有函数声明为全局对象的成员，如 global.add = [function definition] 。但是我必须通常将该函数称为 global.add（）。它的锅炉板比必要的多。

One solution in CoffeeScript I found is by declaring all functions as member of a global object like global.add=[function definition]. But then I have to normally call the function as global.add(). And it's more boiler plate than necessary.

有没有简单的黑客攻击？或者更简单的解决方案？

Is there a simple hack? Or any simpler solution?

推荐答案

您的 add 是一个局部变量。使用

Your add is a local variable. Use

@add=(a,b)->a+b

将其附加到全局对象。由于 global 是您脚本的全局范围，您仍然可以调用 add ，而不用作为前缀全球。。

to attach it to the global object. Since global is the global scope of your script you can still call add without prefixing it with global..

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