javascript：递归匿名函数？ [英] javascript: recursive anonymous function?

问题描述

假设我有一个基本的递归函数：

Let's say I have a basic recursive function:

function recur(data) {
    data = data+1;
    var nothing = function() {
        recur(data);
    }
    nothing();
}

如果我有一个匿名函数，我怎么能这样做...

How could I do this if I have an anonymous function such as...

(function(data){
    data = data+1;
    var nothing = function() {
        //Something here that calls the function?
    }
    nothing();
})();

我想要一种方法来调用调用此函数的函数...我见过脚本某处（我记不清哪里）可以告诉你一个被调用的函数的名称，但我现在还记不起任何信息。

I'd like a way to call the function that called this function... I've seen scripts somewhere (I can't remember where) that can tell you the name of a function called, but I can't recall any of that information right now.

推荐答案

您可以为函数命名，即使您将函数创建为值而不是函数声明语句。换句话说：

You can give the function a name, even when you're creating the function as a value and not a "function declaration" statement. In other words:

(function foo() { foo(); })();

是一个堆栈式递归函数。现在，那说，你 可能不可能不想这样做一般来说，因为各种Javascript实现存在一些奇怪的问题。 （ note —这是一个相当古老的评论; Kangax博客文章中描述的一些/很多/所有问题可以在更现代的浏览器中修复。）

is a stack-blowing recursive function. Now, that said, you probably don't may not want to do this in general because there are some weird problems with various implementations of Javascript. (note — that's a fairly old comment; some/many/all of the problems described in Kangax's blog post may be fixed in more modern browsers.)

当你给出这样的名字时，这个名字在函数之外是不可见的（好吧，它不应该是;这是奇怪之一）。它就像Lisp中的letrec。

When you give a name like that, the name is not visible outside the function (well, it's not supposed to be; that's one of the weirdnesses). It's like "letrec" in Lisp.

至于 arguments.callee ，这在严格模式下是不允许的通常被认为是一件坏事，因为它会使一些优化变得困难。它也比人们预期的要慢得多。

As for arguments.callee, that's disallowed in "strict" mode and generally is considered a bad thing, because it makes some optimizations hard. It's also much slower than one might expect.

编辑—如果你想拥有一个可以调用自身的匿名函数的效果，你可以做这样的事情（假设你把这个函数作为一个回调或类似的东西传递）：

edit — If you want to have the effect of an "anonymous" function that can call itself, you can do something like this (assuming you're passing the function as a callback or something like that):

asyncThingWithCallback(params, (function() {
  function recursive() {
    if (timeToStop())
      return whatever();
    recursive(moreWork);
  }
  return recursive;
})());

它的作用是定义一个具有漂亮，安全，未破坏的IE功能的函数声明语句，创建一个名称不会污染全局名称空间的本地函数。包装器（真正的匿名）函数只返回本地函数。

What that does is define a function with a nice, safe, not-broken-in-IE function declaration statement, creating a local function whose name will not pollute the global namespace. The wrapper (truly anonymous) function just returns that local function.

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