There is almost no difference. In fact the there is an old saying about closures and objects. Closures are the poor man’s object, and objects are the poor man’s closure. Both are equally powerful in terms of what they can do. We are only arguing over expressiveness. In Java we are modeling closures with Anonymous … Read more
A method reference is not a lambda expression, although they can be used in the same way. I think that is what is causing the confusion. Below is a simplification of how Java works, it is not how it really works, but it is close enough. Say we have a lambda expression: Runnable f = … Read more
Check the introduction in this: http://jibbering.com/faq/faq_notes/closures.html. It can help you understand better how closures relate to functions. Here is a set of closure examples: http://www.javascriptkit.com/javatutors/closures2.shtml Basically, the callback is like a function pointer. The bit that makes it a closure, is when that function accesses anything on the context where it lives, like variables outside … Read more
The reason is that closures (lambdas or otherwise) close over names, not values. When you define lambda x: test_fun(n, x), the n is not evaluated, because it is inside the function. It is evaluated when the function is called, at which time the value that is there is the last value from the loop. You … Read more
In order to understand this you must know what is the difference between a function call and a reference to a function. As well as how scopes work in javascript. Assuming you do know these things, let’s get explaining. So you first have a variable hidden that is being assigned a value of mystery(3). So … Read more
No, at most two instances of function’s local data will be held in memory at any given point in time. Here is the order of events: animate(0) is called. A closure with param == 0 is created, it now prevents this variable from being released. Timeout fires, animate(1) is called. New closure with param == … Read more
I think you want to use find instead of each (at least for the specified example). Closures don’t directly support break. Under the covers, groovy doesn’t actually use a closure either for find, it uses a for loop. Alternatively, you could write your own enhanced version of find/each iterator that takes a conditional test closure, … Read more
The problem you have here is that the variable item changes with each loop. When you are referencing item at some later point, the last value it held is used. You can use a technique called a closure (essentially a function that returns a function) to quickly scope the variable differently. for (var i in … Read more
You do, indeed, need to implement a closure here. This should work (let me know – I didn’t test it) var blah = xmlres.getElementsByTagName(‘blah’); for(var i = 0; i < blah.length; i++) { var td = document.createElement(‘td’); var select = document.createElement(‘select’); select.setAttribute(“…”, “…”); select.onchange = function(s,c,a) { return function() { onStatusChanged(s,c,a); } }(select, callid, anotherid); … Read more