anonymous-function

问题 I ran into a problem in IE8 today (Note that I only need to support IE) that I can't seem to explain: detachEvent wouldn't work when using a named anonymous function handler. document.getElementById('iframeid').attachEvent("onreadystatechange", function onIframeReadyStateChange() { if (event.srcElement.readyState != "complete") { return; } event.srcElement.detachEvent("onreadystatechange", onIframeReadyStateChange); // code here was running every time my iframe's readyState // changed to

问题 I asked this question a while back and was happy with the accepted answer. I just now realized, however, that the following technique: var testaroo = 0; (function executeOnLoad() { if (testaroo++ < 5) { setTimeout(executeOnLoad, 25); return; } alert(testaroo); // alerts "6" })(); returns the result I expect. If T.J.Crowder's answer from my first question is correct, then shouldn't this technique not work? 回答1: A very good question. :-) The difference: The difference between this and your

问题 There's something I don't understand about anonymous functions using the short notation #(..) The following works: REPL> ((fn [s] s) "Eh") "Eh" But this doesn't: REPL> (#(%) "Eh") This works: REPL> (#(str %) "Eh") "Eh" What I don't understand is why (#(%) "Eh") doesn't work and at the same time I don't need to use str in ((fn [s] s) "Eh") They're both anonymous functions and they both take, here, one parameter. Why does the shorthand notation need a function while the other notation doesn't?

问题 I've found some solutions to a sorting problem I've been having, but the code uses anonymous functions in PHP. Im using version 5.2.17 and I believe anonymous functions are not supported. How would I change the following blocks of code so I can use them in PHP 5.2.17 $keys = array_flip($order); usort($items, function($a, $b) use($keys) { return $keys[$a['id']] - $keys[$b['id']]; }); from PHP sort multidimensional array by other array And $sorted = array_map(function($v) use ($data) { return

问题 This question already has answers here : Closed 8 years ago . Possible Duplicates: What is Closures/Lambda in PHP or Javascript in layman terms? What is the difference between a 'closure' and a 'lambda'? Hi, I have been unable to find a definition that clearly explains the differences between a closure and an anonymous function. Most references I have seen clearly specify that they are distinct "things" yet I can't seem to get my head around why. Could someone please simplify it for me? What

问题 I see a lot of code like: var myApp ={}; (function() { console.log("Hello"); this.var1 = "mark"; //"this" is global, because it runs immediately on load. Caller is global myApp.sayGoodbye = function() { console.log("Goodbye"); }; })(); Which causes the anonymous function to execute immediately. But what is the advantage of this, compared to just putting the code inline? var myApp ={}; console.log("Hello"); var1 = "mark"; myApp.sayGoodbye = function() { console.log("Goodbye"); }; Apparently it

问题 How to get the the variable name from within a function in this example: // it should return A var A = function(){ console.log(this.name); } Is there something like this? 回答1: That function is anonymous; it has no name. You could, however, give it a name: var A = function a() {}; Then its name is accessible via Function.name: var A = function a() {}; A.name > 'a' 回答2: I know this is an old thread, but still in search results. so just for reference: a solution could simply be using the

问题 This question isn't terribly specific; it's really for my own C enrichment and I hope others can find it useful as well. Disclaimer: I know many will have the impulse to respond with "if you're trying to do FP then just use a functional language". I work in an embedded environment that needs to link to many other C libraries, and doesn't have much space for many more large shared libs and does not support many language runtimes. Moreover, dynamic memory allocation is out of the question. I'm

问题 Can anybody explain to me why A is true and B is false? I would have expected B to be true as well. function MyObject() { }; MyObject.prototype.test = function () { console.log("A", this instanceof MyObject); (function () { console.log("B", this instanceof MyObject); }()); } new MyObject().test(); 回答1: this is special. It refers to the object that the function is being called on behalf of (most commonly via dot syntax). So, in the case of A , the function is being called on behalf of a new

问题 I know that this is not what anonymous functions are made for, but just as a puzzle I tried to make a recursive function via anonymous functions. The prototype of recursive functions obviously is the factorial function. The problem is that it is difficult to make a case distinction within the anonymous functions. What I managed to do so far is following: f=@(cn,n,f)eval('if n>1; f(cn*n,n-1,f);else;ans=cn;end'); f=@(n)f(1,n,f); Or alternatively: f=@(cn,n,f)eval('if n>1; f(cn*n,n-1,f);else;disp