JavaScript is the original and common name applied towards most flavors of a scripting language that originated on NetScape Navigator. Use this tag for questions regarding common implementations of ECMAScript, JavaScript, JScript, etc. JS does not typically refer to its ECMA-cousin, ActionScript.

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3answers
1k views

XSLT equivalent for JSON

I was interested in finding (or if necessary developing) an XSLT equivalent for JSON. As I have not found any, I was considering the possible query language to use for matching JSON paths so as to ...
2
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2answers
356 views

should I test this public method

I have the following simple implementation: var VALIDATION_TYPES = { ERROR: 1, WARNING: 2 }; var validationRules = {}; this.addErrorRule = function (event, rule) { ...
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2answers
12k views

How to run C++ code in browser using asm.js?

An asm.js application is very fast (near native C++ speed): http://kripken.github.io/mloc_emscripten_talk/micro4b.png But how is it possible to write one in C++, convert it to LLVM code, then do ...
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7answers
2k views

Is there a pattern for a more “natural” way of adding items to collections? [closed]

I think the most common way of adding something to a collection is to use some kind of Add method that a collection provides: class Item {} var items = new List<Item>(); items.Add(new ...
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2answers
219 views

What is the best way to create dynamically a DOM?

I know that there are plenty answers to this question on stackoverflow, but I can´t find one that give me an answer that can help me to solve a question that came out after read a lot of Javascript, ...
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0answers
43 views

Performance increase by only attach onblur handler inside of onfocus handler?

Given a web page with input fields, does it have a performance difference whether or not you assign the onblur handler inside of the onfocus handler like so: var inputFields = ...
0
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4answers
264 views

Identifying user of a webapp

For a small webapp I want to be able to identify a user. The issue is, if the user cheats in some manner, I want to be able to forbid him the usage of my application. I already have done extensive ...
9
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3answers
2k views

Are there open-source JavaScript libraries addressing multiple browser tabs and client state for newer browsers? [closed]

There are a few new HTML5 features that have made it into recent browsers that allow sharing state among tabs, browser windows, same domain windows, etc. So it's probably gotten a little easier to ...
219
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7answers
17k views

Does using == in JavaScript ever make sense?

In JavaScript, the Good Parts, Douglas Crockford wrote: JavaScript has two sets of equality operators: === and !==, and their evil twins == and !=. The good ones work the way you would expect. ...
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2answers
135 views

How to convert a number into sum of numbers of specific length

I am trying to convert a number(x) into array of numbers so that their sum is equal to the number (x), but the array length should be equal to the given length. var x = 12 length 1: [12] = ...
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1answer
88 views

jQuery event binding management

Given the following elements: <div class="container"> <span class="some-class">content</span> ..n span repetitions.. </div> Given the following .on() ...
24
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8answers
21k views

Why almost no webpages hash passwords in the client before submitting (and hashing them again on the server), as to “protect” against password reuse?

Relevant XKCD There are many sites on the Internet that require login information, and the only way to protect against password reusing is the "promise" that the passwords are hashed on the server, ...
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1answer
103 views

How should I structure an application containing business logic and display? [duplicate]

I'm working on a simple board game that will run in the browser. I'm thinking how to structure the program and I'd like to hear your opinions. The program will consist of the user interface part (the ...
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0answers
300 views

JavaScript program design: to what degree should I separate logic and display?

Consider you wanting to implement a simple game of checkers. There would be a rectangular game board and the player would able to move the pieces around according to a particular set of rules. ...
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0answers
39 views

Why does JSF not tend to render specific value to constant in some tags

This question is about JSF concepts or architecture; probably I don't understand enough to be more specific. There are some ways to pass parameters to commandLink actionListener. But there are no ...
14
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7answers
5k views

Would Python be too slow for client-side use in Browsers?

I've heard the statement that Python would be too slow to be of any use in browsers. I reckon Javascript is only superior in this aspect because of companies like Google who need it fast (and made it ...
0
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3answers
219 views

Online code editors programming language

When searching for online code editors (out of interest how all the course sites such as Codecademy has been made) I noticed they are all been written in JavaScript. Why are all those code editors ...
3
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2answers
372 views

How do I integrate a browser-based JavaScript unit testing framework into my workflow?

I'm wondering how I seamlessly include a JavaScript unit testing framework into my workflow. The context is, we have an existing data processing algorithm + webapp to display it, with no automated ...
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2answers
435 views

Is it possible to protect client side algorithms 100%? [duplicate]

If you had a pretty novel idea that involved a new algorithm. Like lets say you were the first person to think of orbitz.com or kayak.com (travel sites) and you were able to and wanted to implement ...
3
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3answers
3k views

How do I prevent useless content load on the page in responsive design?

In responsive design, elements are hidden in the page with @media queries and display: none in CSS. Ok. In my design however browsers that have less than 800px in width should avoid loading some ...
3
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2answers
87 views

Is it reasonable to have grunt/gulp build phases in javascript dev environment

Nowdays it's goes to be very fancy to have grunt/gulp build phases who concatenate and minify and organize javascript code. And I agree that this is important for production. But as a developer, I ...
3
votes
1answer
174 views

How do I create a modal service with AngularJS?

I'm trying to make a service that's polymorphic based upon what mode is specified in the URL. If the char param in the route is set to 'p', I want to use a PresentMode service. If the char param is ...
0
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1answer
119 views

Do I need Bower for front end dependencies when I am already using composer?

I use composer for PHP dependencies. I was under the impression that for front end dependencies I should use Bower. So, I installed Bower and loaded my FE dependencies (Bootstrap, jQuery) using that. ...
3
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1answer
92 views

What is the correct way to publish a runtime? Should it be a singleton?

I have a compiler for a programming language that targets JavaScript. That language needs some global functions such as: alloc, memcpy, write and so on. My question is: where should I position those ...
1
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1answer
54 views

Is having a parent controller to manage a set of tabbed sections an anti-pattern for an angular application?

A lot of times, I have long forms that I divide into multiple tabbed sections. Each section is managed by it's own controller and there is a parent controller that manages the whole view. I use ...
1
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1answer
163 views

Relatively large data on client side in web application

We are discussing on building a web application where (as per clients requirement), there will be relatively large data (60,000 items) to be shown as tree view. Let's assume each item is string of ...
2
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2answers
135 views

Naming self or this something else, a good idea?

I'm finding that my code becomes more readable when I make a local reference to this/self, and/or call it something that makes sense in the context. "self" or "this" doesn't really indicate what kind ...
4
votes
1answer
338 views

What is the best way to format complex SQL queries in Node?

I am using node-mysql to query a MySQL database via Express and Node. My queries are getting fairly complex and I want to format them across multiple lines. However, the only way I could accomplish ...
0
votes
1answer
101 views

MVC: Inserting a view from a SubController to its Parent controller

I have 2 controllers: 1 top level controller,MainController, and a SubController, which MainController has an instance of and controls. The SubController has a Subview which goes inside the MainView ...
1
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2answers
250 views

Common techniques to integrate social media login to a website that requires account registration

I have developed websites where users would register with a username of their choice and an entry would be created in a database table that holds their username and some sort of salted password. They ...
2
votes
1answer
760 views

How can I keep Web services requests in a DAO layer without tying the code to the DOM?

I'm working on a single page application on the node-webkit desktop app platform, which means 99.9% of all of the logic is written in JavaScript. Since this is a reboot of a project we're working on, ...
3
votes
5answers
220 views

How do you unit test a function that clears properties?

I have a very common function that I have always unit tested in the same way, but I'm wondering if there is a better solution or if it's even possible a code smell is involved. It seems like a very ...
0
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1answer
112 views

JavaScript strict mode compatibility

While reading about strict mode on MDN I really was surprised to read the following near the end of the page, quote: Browsers don't reliably implement strict mode yet, so don't blindly depend on ...
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1answer
353 views

The Better Parts and Delegation: Is Crockford Too Extreme?

Douglas Crockford has recently been giving a talk called The Better Parts. The gist of the talk is that JavaScript developers should actually avoid a superset of the The Bad Parts, which now includes ...
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1answer
56 views

Compose nested EventEmitters elegantly

I am developing a server-side JavaScript tool, and trying to do so in a modular way. I have a Parser class that is an EventEmitter - you call parse and it will eventually emit data and end events. It ...
3
votes
6answers
776 views

When to use a API/Library and when to write your own?

I am working on a large website and having been thinking a lot about when I should be using a 3rd party API/Library and when I should be writing my own implementation from scratch. There is no Library ...
3
votes
4answers
294 views

What programming mindset to have towards JavaScript? [duplicate]

I used to program in Java. As a result of that I got well-versed with Object Oriented Paradigm. In my opinion it is a great approach to programming because it's easy to unit test, use design patterns, ...
1
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1answer
156 views

Why do browser Javascript libraries pass the window object as an argument?

While looking at various JavaScript libraries, I have noticed a relatively common practice of passing either the window or the document object as part of the arguments given to the library ...
2
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1answer
102 views

AJAX - What exactly does that encompass? [closed]

So I see on a lot of people's resumes they list AJAX in their technologies (or programming languages - and I recognize that it is not a language). To me, AJAX seems like such a small concept to be ...
1
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2answers
2k views

Using WebStorm for Razor Syntax MVC

I am building a lot of client-side heavy SPA-like apps with VS2010 and MVC3/4. VS2010 Javascript/HTML/CSS editing (mostly javascript) is interminably slow and sluggish. I'd love to use something ...
4
votes
1answer
182 views

(jQuery) What is wrong with methods such as .append?

tl;dr: What is wrong with the efficiency of methods such as .append() and what can be alternatives to this? Explanation: Hello everyone. I occasionally have to build A/B tests for websites, which ...
15
votes
2answers
675 views

Why does XMLHttpRequest not seem to follow a naming convention?

I've been working with the XMLHttpRequest object in JavaScript recently, and I couldn't help but notice that the casing of this name makes no sense. Why is 'XML' all in caps while 'Http' is not? ...
6
votes
5answers
427 views

Using π, φ, λ etc. as variable names while programming? [duplicate]

This is a function in the d3.v3.js file (the graph library D3.js): function d3_geo_areaRingStart() { var λ00, φ00, λ0, cosφ0, sinφ0; d3_geo_area.point = function(λ, φ) { ...
0
votes
2answers
2k views

Javascript storing data [closed]

Hi I am a beginner web developer and am trying to build the interface of a simple e-commerce site as a personal project.The site has multiple pages with checkboxes. When someone checks an element, it ...
0
votes
2answers
127 views

Porting an algorithm implementation licensed under GNU GPL v3

I'm working on a JavaScript port of a red-black tree implementation in Java from the book Algorithms 4th Edition, by Sedgewick and Wayne. I believe that my JavaScript port qualifies as a derivative ...
45
votes
2answers
24k views

When not to use Google Web Toolkit? [closed]

I'm considering use of GWT on a major in-house web app development project, namely it's major advantage in my eyes is the cross-compilation to Javascript which would (at least theoretically) help my ...
3
votes
3answers
195 views

Easy way to make old javascript files conform to new quoting standard?

We've just started putting linting in place at my workplace, and a lot of the devs didn't realize our standards called for double-quotes everywhere. About 50% of the codebase uses single-quotes, so ...
5
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4answers
711 views

Design Patterns for Coordinating Change Event Listeners

I've been working with the Observer pattern in JavaScript using various popular libraries for a number of years (YUI & jQuery). It's often that I need to observe a set of property value changes ...
58
votes
14answers
6k views

Is it a bad idea to return different data types from a single function in a dynamically typed language?

My primary language is statically typed (Java). In Java, you have to return a single type from every method. For example, you can't have a method that conditionally returns a String or conditionally ...
2
votes
1answer
167 views

moving around virtual keyboard

I'm creating virtual keyboard using javascript/html/css. And I can't find a good algorithm for moving from one button to another in different directions (top-bottom, left-right). Lets say I ...