问题描述
有时我们需要通过函数名来调用函数.我可以用纯 JavaScript 来完成,如下所示:
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)
按预期工作,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)
编译成 JavaScript 为:
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.
Microsoft JScript runtime error: Object doesn't support this property or method
这个问题有简单的解决方法吗?
Is there an easy solution to this problem?
注意:
我没有在浏览器中运行代码,因此没有窗口对象.但是在普通的 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.
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像 global.add=[function definition]
这样的全局对象的成员.但是我通常必须将该函数称为 global.add()
.而且它比必要的样板更多.
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.
有简单的技巧吗?还是有更简单的解决方案?
Is there a simple hack? Or any simpler solution?
推荐答案
你的 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 global
对象.由于 global
是脚本的全局范围,您仍然可以调用 add
而无需在其前面加上 global.
.
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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