ActionScript “Next”
The range of applications and content for ActionScript has shifted significantly in recent years, while the ActionScript 3 language remains virtually unchanged since its introduction in 2006. Adobe believes it is time torevise the language to carefully steer its further evolution towards greater expressiveness as well as productivity and performance gains.
From a language design standpoint, Adobe uses the following assumptions as a guide for next-generation ActionScript development:
[list][]Increasing demand for long-term productivity benefits such as robustness, modularity, and maintainability to complement shorter-term productivity benefits characteristic of scripting languages, such as speed of development
[]Demand for high performance increases
[*]Demand for hardware utilization increases[/list]
First, Adobe plans to make significant performance increases in the short term with a goal of continuing performance improvements over the long term. Performance is the primary goal when we approach how to evolve ActionScript. Second, Adobe aims to increase developer productivity by simplifying the language, improving tool support, and boosting bug prevention. Finally, having reduced unnecessary complexity, we will be in a position to innovate within the Flash runtimes much more quickly.
Below are a couple of items being explored for the next generation of the ActionScript language and Virtual Machine:
[list][]Stringent static typing as default, with optional dynamic typing: Most stretches of most programs are expected to benefit from static typing. However, ActionScript 3 tends to lapse into dynamic typing all too easily in places where absolutely stringent static typing would be preferable. This will be corrected. Dynamic typing will still be available when needed, but it will no longer be the default for ActionScript, and it will need to be enabled explicitly.
[]** Type inference**: Type declarations will only be necessary in certain strategic places. Everywhere else the compiler will automatically infer suitable type declarations and treat the whole program as statically typed, even though the programmer does not have to state any types. Thus the convenience of untyped programming can be approximated quite well, while providing the performance advantages of typed programming.
[*]** Hardware-oriented numeric types**: For example, int, uint, float, float4, byte, short, long, etc. (the exact set of types is still under discussion). Currently in ActionScript 3 integer values can overflow into floating point values. This will be changed so that numeric operations will never change the underlying representation of the numeric. We foresee this addition greatly reducing implementation complexity and improving runtime performance.[/list]
These are just a couple of areas that we are focusing on. We will update this document as our thinking evolves and solidifies around how the language and virtual machine will change.
