closures

问题 I want to add a new image in each cell of the new table and give it the same source as the old table, and then make it clickable. Firstly, I did this: function showData() { if (localStorage.getItem(name) !== null) { var showme = localStorage.getItem(name); alert("I got the table"); var newTable = document.createElement('table'); newTable.innerHTML = showme; newTable.id = "newTable"; newNumRows = newTable.getElementsByTagName('tr').length; newNumCells = newTable.getElementsByTagName('td')

问题 I want to add a new image in each cell of the new table and give it the same source as the old table, and then make it clickable. Firstly, I did this: function showData() { if (localStorage.getItem(name) !== null) { var showme = localStorage.getItem(name); alert("I got the table"); var newTable = document.createElement('table'); newTable.innerHTML = showme; newTable.id = "newTable"; newNumRows = newTable.getElementsByTagName('tr').length; newNumCells = newTable.getElementsByTagName('td')

问题 Here's a compose function that can compose Fn closures: fn compose<'a, T1, T2, T3, F1, F2>(f: F1, g: F2) -> Box<Fn(T1) -> T3 + 'a> where F1: Fn(T1) -> T2 + 'a, F2: Fn(T2) -> T3 + 'a { box move |x| g(f(x)) } How do I make it so that this compose function can take FnMut closures? I tried: fn compose<'a, T1, T2, T3, F1, F2>(f: F1, g: F2) -> Box<FnMut(T1) -> T3 + 'a> where F1: FnMut(T1) -> T2 + 'a, F2: FnMut(T2) -> T3 + 'a { box move |x| g(f(x)) } But it complains about: error: cannot borrow

问题 I understand that there is global scope, and additionally nestable functional scope . But are there any other types of scopes or closures in Javascript? While we're on the topic, what's the difference between a scope, and a closure? 回答1: A closure is a stack of visible scopes. Let's say you have the following code: var v1; function a() { var v2; function b() { var v3; function c() { var v4; } return c; } return b(); } var f = a(); c is a function that has 4 visible scopes: its own scope

问题 Me and my loops again... I'm trying to run a for loop across several div s, each being in the class " tooltipBox " but with different id s. In each of these div s is an input text field with class " tttFalloutOrder ". What I want to do in the for loop is to attach a click-event-listener on each .tttFalloutOrder input field. This is my code so far: function installListener(elementId) { $( "div#" + elementId + " > .tttFalloutOrder" ).on("click", function() { alert("clicked on " + elementId); })

问题 This question already has an answer here : Cannot move out of borrowed content when unwrapping (1 answer) Closed last year . I want to iterate over a vector using .iter_mut() and .map() : fn calculate_distances(planes : &mut Vec<Aeroplane>, x: f64, y: f64) { fn calculate_distance(x1: &f64, y1: &f64, x2: &f64, y2: &f64) -> f6 { ... } planes.iter_mut().map(|a| if a.position.is_some() { let pos: &Position = &a.position.unwrap(); a.distance = Some(calculate_distance(&x, &y, &pos.latitude, &pos

问题 This question is a continuation of the comments at Using Local Special Variables, regarding how best to avoid global variables. As I understand it, global variables are problematic mainly because they have the potential to interfere with referential transparency. Transparency is violated if an expression changes a global value using information outside its calling context (eg, a previous value of the global variable itself, or any other external values). In these cases evaluating the

问题 I am new to JavaScript and I currently studying closures. Below you can see my code that is supposed to print any given array with a specified separator between each element. The thing is that if i try to create an array and print it in the makePath() function, everything works just fine. But when I try to do the same in the main function, it just doesn't work. I also have one more problem when I try to join the separator with the array, The separator is printed at the end of the list and I

问题 func loadMe() -> Void { println(me.initUrl()); let url:NSURL = NSURL(string:me.initUrl()) let request:NSURLRequest = NSURLRequest(URL:url) let queue:NSOperationQueue = NSOperationQueue() NSURLConnection.sendAsynchronousRequest(request, queue:queue, completionHandler:{response, data, error in if data { var jerr:NSError? var json:NSDictionary = NSJSONSerialization.JSONObjectWithData(data, options:NSJSONReadingOptions.MutableContainers, error:&jerr) as NSDictionary if !jerr { println(json

问题 This may be a duplicate. I don't know. I couldn't understand the other answers well enough to know that. :) Rust version: rustc 1.0.0-nightly (b47aebe3f 2015-02-26) (built 2015-02-27) Basically, I'm passing a bool to this function that's supposed to build an iterator that filters one way for true and another way for false. Then it kind of craps itself because it doesn't know how to keep that boolean value handy, I guess. I don't know. There are actually multiple lifetime problems here, which