Despite the fact that ActionScript has a couple of major glitches and missconceptions I think there are also a couple of great key features that force you to write better applications due to the language design.
First of all we have to aknowledge that ActionScript has some great features. Those include implicit getters and setters or method closures for instance. Java 7 will have method closures finally after a lot of argy-bargy about their complexity et cetera. ActionScript developers are used to method closures and are buddy-buddy with them since Flash 4 I think.
But what is the real advantage of ActionScript? Here are my thoughts.
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Poor Performance
Yes. We have been educated to optimize the hell out of our code. We have been educated to think about our code and how it performs. We have been educated to be creative with our tools, to tinker around. I know that this is not something to be essentially proud of but it led to a lot of creative and astonishing experiments. If you would tell a Java programmer you are still developing object pools they will laugh at you for a good reason. This is where the poor performance is annoying but something is very important: the potential. Think with the mind of a carpetbagger. Shares on the stock-market that never have a downturn are less interesting because there is less profit potential. So why am I talking about this? It is quite simple: Flash has still a lot of potential for growth. Flash did not pass its zenith already like other virtual machines. This makes me very optimistic for the future. There is still so much potential for the growth in performance and I think that Apparat has shown this as well.
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Forced Asynchronism
ActionScript has no ability to perform blocking operations (despite of AIR). This makes every application responsive. If you load files from an external source like a URL your application will stay responsive because you have to add listeners that react on certain events. I know this is somtimes cumbersome but every good application should make use of asynchronous IO for instance. If people are lazy they will simply spawn a new thread to perform blocking operations which is also okay but less performant. Usually the simple example is a server where you would spawn a new thread for every client. This is the worst you can do and Java tackles this issue with its NIO. However a lot of people do not make use of NIO because they think it is hard to use for common tasks.
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Events
Events are a great way to achieve concurrency. Some people call this immutable message passing. If your events do not contain state or are immutable, you have a powerful system to tackle concurrency. Basically this is what the EventDispatcher is all about. You add listeners for certain messages to a dispatcher and then you react on a message when it is dispatched to you. Again we have been educated to use a system which forces us to write responsive applications that is not based on synchronization and locks like Java or C++. If Adobe decides to implement multithreading in the Flash Player I hope they will choose to implement the approach of Erlang which is all about immutable events and event dispatchers. The only difference is that Erlang programmers call them actors.
This post is not an ode to ActionScript. There are still major issues like the lack of parameterized types. But I do think that there is a lot of potential. We can grow with the language and we can tackle upcomming issues. Concurrency is one of them, limited resources on a mobile device are another one.
