Sharing my thoughts on software development

Friday, July 29, 2011

Visual Studio Website Project vs Web Application Project

There probably has been billions of articles written about this topic, and I am no expert who understands the full extent on how the two types of project differ from each other. However, most of those articles are fairly old, and the year 2011 deserves a new article about this topic. :)

So if you are a developer working in a Microsoft shop, chances are you would use at least one of the following: ASP.NET MVC, NuGet, Unity Application Block, Unit Test, Gated Check-in, custom build event/script.

If you use any of those consistently in your projects, it's probably best to stick with Web Application Project, some of them (i.e. ASP.NET MVC) flat out cannot work with Website Project; some would, but requires non-typical setup which you have to investigate and assess.

Conclusion: in year 2011, if you are not sure, use Web Application Project.

Thursday, July 28, 2011

CoffeeScript global variable and @ keyword

I finally managed to pick up CoffeeScript, by writing a small game using CoffeeScript and Canvas. Writing code with CoffeeScript is a very fluent experience, even though I have never used Ruby and have C# background, the syntax feels so natural and code enjoyable to write. All the good things aside, I also got caught by a little gotcha of the language.

In the world of CoffeeScript, global variables must be explicitly declared, using either @ or window keyword, and most tutorials recommend @ due to its succinctness:

@luckyNumber = 4

this attaches luckyNumber into window object and thus accessible globally. The tricky thing is if you do the same declaration in a class:

class MyClass
  constructor: (@luckyNumber = 5) ->

all of sudden, @luckyNumber becomes a property of MyClass, and is not attached to the window object anymore! Now consider following situation:

@luckyNumber = 4
class MyClass 
  constructor: (@luckyNumber = 5) ->

  showLuckyNumber: () ->
    alert(@luckyNumber)

(new MyClass).showLuckyNumber()


Is it going to give you 4 or 5? ... Yes you probably guessed right, it's 5. To access the global variable, you need:

showLuckyNumber: () ->
    alert(window.luckyNumber)

While tricky, this is not exactly a CoffeeScript problem, but weirdness inherited from Javascript. Remember the golden rule: "It's just JavaScript".