I’m trying my hardest to wrap my head around JavaScript closures. I get that by returning an inner function, it will have access to any variable defined in its immediate parent. Where would this be useful to me? Perhaps I haven’t quite got my head around it yet. Most of the examples I have seen … Read more
I saw the following in the source for WebKit HTML 5 SQL Storage Notes Demo: function Note() { var self = this; var note = document.createElement(‘div’); note.className=”note”; note.addEventListener(‘mousedown’, function(e) { return self.onMouseDown(e) }, false); note.addEventListener(‘click’, function() { return self.onNoteClick() }, false); this.note = note; // … } The author uses self in some places (the … Read more
What does the Python nonlocal statement do (in Python 3.0 and later)? There’s no documentation on the official Python website and help(“nonlocal”) does not work, either. 9 Answers 9
I’m checking out some PHP 5.3.0 features and ran across some code on the site that looks quite funny: public function getTotal($tax) { $total = 0.00; $callback = /* This line here: */ function ($quantity, $product) use ($tax, &$total) { $pricePerItem = constant(__CLASS__ . “::PRICE_” . strtoupper($product)); $total += ($pricePerItem * $quantity) * ($tax + … Read more
In javascript, when would you want to use this: (function(){ //Bunch of code… })(); over this: //Bunch of code… 20 s 20 It’s all about variable scoping. Variables declared in the self executing function are, by default, only available to code within the self executing function. This allows code to be written without concern of … Read more
A friend of mine and I are currently discussing what is a closure in JS and what isn’t. We just want to make sure we really understand it correctly. Let’s take this example. We have a counting loop and want to print the counter variable on the console delayed. Therefore we use setTimeout and closures … Read more
How can I create static variables in Javascript? 44 s 44
Could someone explain? I understand the basic concepts behind them but I often see them used interchangeably and I get confused. And now that we’re here, how do they differ from a regular function? 15 s 15 There is a lot of confusion around lambdas and closures, even in the answers to this StackOverflow question … Read more
Closed. This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 6 years ago. Improve this question I’m trying to figure out Python lambdas. Is lambda one of those “interesting” language items … Read more
var funcs = []; // let’s create 3 functions for (var i = 0; i < 3; i++) { // and store them in funcs funcs[i] = function() { // each should log its value. console.log(“My value: ” + i); }; } for (var j = 0; j < 3; j++) { // and now … Read more
