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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Preserving Pre-formatted Multi-Line Strings in Node.js Scripts

There is a lot I don't like about PHP, but one thing I love is multi-line strings: $query = <<<EOT select field1 ,field2 ,field3 from tableName where field1 = 123 EOT; ...
22
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2answers
1k views

Is there any reason to use the “var” keyword in ES6?

Babel's guide to ES6 says: let is the new var. Apparently the only difference is that var gets scoped to the current function, while let gets scoped to the current block. There are some good ...
2
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1answer
102 views

How to deal with server-side and client-side naming conventions that clash? [closed]

I have a project that uses the underscore naming convention for the MySQL database and PHP scripts but uses camelCase for the javascript application (a common scenario I'm sure). However, once JSON ...
3
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3answers
355 views

With only backend development experience, how do I go into frontend development (js, html, css)? [closed]

Currently I am interning at a company as a "full stack" developer (Application developer on the job title) and I realize that I am having difficulties coping with frontend tasks. This is especially ...
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1answer
148 views

Better pattern than large if/else if/else for checking conditionals [duplicate]

I've got a fairly large set of booleans I'm checking in javascript, and then using them to alter the state of a layout in my React app. The whole thing is unwieldy, difficult to read, inelegant, and ...
3
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1answer
310 views

What is the most efficient / fastest way to keep a list in order?

I implemented Dijkstra's path finding algorithm in JavaScript and a big part of it involves storing the distances to nodes and fetching the smallest. The distances change often and the smallest is ...
2
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1answer
70 views

How Javascript Engines access/lookup property names?

How Javascript Engines access/lookup property names? what kind of associative array (data structure or search/lookup algorithm) did they use? (for V8, TraceMonkey, JSC, and Rhino) For example, in C++ ...
2
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1answer
84 views

The meaning of 'fully traversable namespaces' in JavaScript

During research into architecture of single page applications, I came across the following resource by Mikito Takada, written around 2013: http://singlepageappbook.com/ In his introduction he ...
2
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1answer
340 views

Does react.js make sense for a static content-driven site?

I'm pretty sold on the react.js model because it makes DOM manipulation so smooth and comprehensible. But I'm wondering how it could be leveraged for a site that's largely static with big blocks of ...
16
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1answer
735 views

When to use prototypical programming in JavaScript

I've spent a good bit of time developing simple widgets for projects in the following way: var project = project || {}; (function() { project.elements = { prop1: val1, prop2: val2 } ...
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0answers
29 views

modelling an ecosystem evolving on a landscape

I would like to understand a bit more the theory and the approaches available in modelling a population roaming across a landscape. Assume discrete time and space as simple as a discrete grid and a ...
4
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1answer
172 views

Does HTML 5 undercut the need for a full-featured Javascript framework? [closed]

We're redesigning a website. Right now it uses Dojo, a large (and complex) Javascript framework. One person insists that we need Dojo because of things like (random examples) client-side ...
5
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2answers
633 views

Where is the evidence for the performance of Node.js?

A lot of developers, especially ones who haven't used Node.js in production, seem to believe that Node.js is faster than other interpreted languages such as PHP, Python, and Ruby. These claims ...
0
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1answer
119 views

Should I prefer classes or singletons in JavaScript/Node?

This question applies especially to Node.js, but also to JavaScript in general. I started working on a simple web app in Node.js. I'm relatively new to Node and JavaScript, and come mainly from C# ...
5
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3answers
272 views

Is prototypal inheritance inherently slower?

I see Javascript 6 will add traditional class based inheritance, and one argument I hear is that classes are inherently much faster than prototypes because they can be optimized away by the compiler ...
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0answers
50 views

Need to add websocket support to a single page that's running a wsgi service

Current setup. I have a legacy ERP system (Thoroughbred) and i then have several in house applications (CRM, WMS) and a website that interact with it via an xml server and straight ODBC connections. ...
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2answers
96 views

Literal strings vs. object properties in JavaScript

JavaScript libraries in the same space (UI widgets) use two different approaches for instantiating components: Literal strings to specify types, and inlining as much as possible, for example: var ...
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2answers
214 views

How to make scalable modules in a div element

I'm interested in creating web modules that are encapsulated by a div element in a manner that, by simply resizing the div, everything in that div scales to the dimensions of that div proportionately ...
0
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1answer
93 views

Measure and locate areas of similar value in an image

I saw this picture online and wanted to see if I could create an algorithm to give ordinary images an effect like this: http://justinlivi.net/wp-content/uploads/2011/01/Living_In_Digital.jpg My idea ...
3
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2answers
162 views

Why is the Document Object Model the view?

I was told by a Javascript programmer not to do DOM manipulation in model code. I also remember hearing a snazzy tune for a JS framework (I forget which one): "Get your models out of the DOM". This ...
0
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0answers
111 views

Reason why client-side JavaScript does not allow access to POST/PUT/etc contents

Is there any theoretical reason why client-side JavaScript could not be spec'd to allow for direct access to POST or PUT contents without need for a server language to write it into client-side ...
0
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1answer
55 views

Choose approaches for updating an object

Say I have a simple object created by from user input: var input = { url: 'http://example.com/', path: 'abc', user: 'adam' }; And I am to write function(s) that update url and path properties ...
1
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1answer
202 views

Using streams to connect programming languages

I'm trying to run a computation-heavy program that creates an image on a website. Is it possible to compute in C++ and have an output stream that connects to an input stream in Node.js to display an ...
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0answers
67 views

Login Tokens Remote DataServer for use in a Javascript/HTML-PHP environment

I've asked this question on stackoverflow, but i think this is a more appropriate place for it. I'm creating an app for iOS, Android and the Web. I created a separate Restful Data Service that is ...
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0answers
123 views

What's the Difference with these Knockout Viewmodel constructors?

When creating a viewmodel for Knockout, what's the difference here? I see these different implementations and I've tried a few and some don't work the same. //the most common example. function ...
2
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3answers
776 views

Why is it a good practice to keep Javascript code in separate files?

In web development we are commonly used to keep Javascript code in separate files, but sometimes we need this Javascript code to manipulate server side data locally. For example, making an Ajax Call ...
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1answer
229 views

What are the benefits of using new over closures

I've been programming in JS for over a year now, mainly in angularJS. And I can honestly say I've never made a function use prototypical inheritance. When ever i need a class like object that has ...
2
votes
2answers
358 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) { ...
13
votes
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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0answers
46 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
votes
2answers
264 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, ...
-3
votes
2answers
150 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] = ...
7
votes
1answer
324 views

Is obtrusive JavaScript required to support a feature of AngularJS?

I'll start by saying I'm just learning about AngularJS, and I was reading this article, which seems to advocate for obtrusive JavaScript as the right thing: ...
0
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1answer
108 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
309 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. ...
0
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4answers
292 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 ...
2
votes
1answer
179 views

Why do browsers clamp timeouts and intervals?

I've been working on some abstractions of setTimeout and setInterval in order to process large sets of data without blocking the event loop in the browser. Upon this, I have discovered that browsers ...
0
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3answers
225 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 ...
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0answers
53 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 ...
1
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2answers
454 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 ...
220
votes
7answers
18k 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. ...
3
votes
2answers
88 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 ...
0
votes
1answer
146 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
votes
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
vote
1answer
97 views

Ideal export in terms of size for asynchronous module definitions in JavaScript?

When creating AMD modules you can export whatever you like whether it be an object or a function. I vaguely recall reading a recommendation somewhere to export just one thing; the idea being "keep it ...
1
vote
1answer
179 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 ...
3
votes
1answer
192 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 ...
1
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1answer
99 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() ...
0
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1answer
116 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 ...
3
votes
5answers
224 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 ...