Lumia 920 is Nokia’s smartphone running Windows Phone 8 that is getting quite popular these days. When using this phone for browsing the web and running web applications, how does it stack up against its competitors?

Complicated code is difficult to digest and hard to maintain. The best way to avoid it is by not having it at the first place. For web applications written in JavaScript, fortunately we have enough tooling machinery to detect complex code and block it from the source repository.

With the popularity of test-driven development (TDD), running a project which does not include an automated test workflow is often frown upon. The recent trend pushes it further: if the code coverage is not measured and monitored during that testing, the confidence level will not be very high. For J...

Modern Android applications tend to follow certain user interface patterns, primarily as described in the official Android UI Guidelines. However, not every application is designed equally. Here we see how three news applications have the overall same look, yet the significant detailed differences a...

One of the common refactoring activities is variable renaming. Many respectable IDEs have such a language-aware renaming feature. In some other cases, this is carried out via a simple search and replace. Manual search replace is error-prone and hence why a syntactically-correct rename refactoring to...

An interesting feature of many programmer’s editors is identifier highlighting. It makes easy to spot where a particular variable or function is used. With JavaScript as the language, highlighting is also useful since some JavaScript beginners are often confused by JavaScript function-level scope an...

One of the major usages of PhantomJS is to capture web pages and render them as image. There are many rendering aspects which can be tweaked, the most popular one is the zoom factor, particularly useful to create thumbnails. A rather not-so-known parameter is the clipping rectangle which is very han...

Back when JavaScript interpreters were still slow, avoiding a function call inside a performance-critical code was very much recommended. With the recent improvements to the modern JavaScript engines, this practice becomes less relevant. One important feature which reduces the need to worry about fu...

In WebKit world, preload scanner refers to a side parser which kicks in if the main HTML parser is halted by a blocking script loading. Because this preload scanner can see what other resources (e.g. stylesheets, images, inputs) are to be fetched, it can trigger the associated network requests as ea...

When writing a large JavaScript application, it is quite often that console.log and other debugging statements are sprinkled here and there. Obviously, at one point those extraneous statements need to be removed for the production version or even when the code needs to be checked in into the source ...

Spring is in the air! Time for me to hit the road and give some tech talks.

Using an object literal populated with some member functions is a common practice in any serious JavaScript applications. This is also useful for all kind of frameworks, in particular to setup object prototypes. The upcoming ECMAScript 6 introduces method definition, a nice shorthand which eliminate...

To have a silky smooth experience on mobile web, it is important to gather relevant performance data so that a suitable optimization can be carried out. Traditionally, such a measurement activity is full of (black) magic since the web browser itself often does not expose enough performance metrics. ...

We have seen how a rest parameter can help the handling of a variable number of function arguments. What about the other way around? Can we turn an array into a series of function arguments? Apparently, ECMAScript 6 defines a new type of operator called the spread operator which does exactly that.

Code autocomplete is probably one of the exciting features of a programmer’s text editor. Ever since Eclipse Orion started to demonstrate its wonderful Content Assist feature last summer, I do believe that an online, web-based editing component should always provide a minimalistic and convenient aut...

Handling a function with a variable number of arguments is always tricky in JavaScript. At least, we still have this arguments object which can be used to retrieve all arguments used to invoke a function. With the upcoming ECMAScript 6, no such hack is necessary anymore since we can start using its ...

Constructing an object using the literal syntax is something that is very familiar to every JavaScript developer, quite likely because this reminds everyone of JSON. While every object property needs to be either a key-value pair or getter/setter, this may change in the near future. Another syntacti...

Last week, the annual W3C conference for web professionals, W3Conf 2013, was held in San Francisco. It was packed with tons of interesting talks. The event was professionally organized and it attracted the attention of various Who’s Whos in the front-end development world.

In the last few years, I have written a lot of technical articles (full archives), shown here organized by topic. Note that some of them have been covered as well in various presentations.

Experienced JavaScript programmers take advantage of function expressions, they are used a lot in callbacks, either for DOM access or any other related setup. Another syntax addition to the upcoming ECMAScript 6 is the arrow function expression to let us write a shorter function expression.

Many programming languages support the concept of a default argument for a function parameter so that the caller does not always need to specify the argument value. Unfortunately, JavaScript does not have a default argument support in its syntax. This may soon change with the upcoming ECMAScript 6.

Scripted (GitHub: github.com/scripted-editor/scripted) is a new JavaScript editing tool from VMware. It is relatively new, the first edition was launched just a few months ago. However, so far it seems to be a capable and usable editor for your JavaScript needs.

In a programming language, destructuring assignment denotes the use of patterns to extract parts of an object. If we refer to Common LISP, destructuring assignment binds a set of variables to a corresponding set of values, where normally bind a value to a single variable. For the next-generation ECM...

As with many professionals, I am occasionally asked for some random career advice by a few young engineers. Since I am usually not the right person to ask, typically what I share are the thoughts and perspectives which I wish I had when I was still early in my career. One of them is the impact facto...

Many modern programming languages support list comprehension, a concise way to create a list based another list where each entry is the result of some operations. If comprehension is used properly, it eliminates the need for the traditional and error-prone manual iteration. Next-generation JavaScrip...

This year starts with a good event, W3Conf, the annual W3C confer­ence for web pro­fes­sion­als. It will be held in San Francisco, 21-22 Feb. There are many interesting talks, featuring a few known experts in the field.

Line drawing of McDonnell Douglas F-4 Phantom II. It has been two years since I decided to announce my fun WebKit tool and to run it as an open-source project, PhantomJS. Better than the situation a year ago, the traction is increasing as more and more users adopt PhantomJS as a helping utility for ...

I have written about the concept and the tool for complexity analysis of JavaScript code before. In addition to that complexity monitoring strategy, apparently it is also useful to produce the so-called complexity report. Fortunately, now we have a visualization tool which allows us to prepare such ...

Update: Read also the performance quick check of Nexus 5, the successor to Nexus 4.

Some Mac OS X users of PhantomJS reported that it crashed every one and then. This also affects other related projects such as Poltergeist. A reduced test case revealed that it has something to do with the use of some TrueType fonts. I decided to investigate this issue and learned a few things along...