I did not plan to write this article, but since I wrote this bunch of classes in few minutes, I thought to share the code with everybody.

I did not invent anything, I just ported the useful Kevin McFarlane’s DesignByContract helper class that I use for my c# Unity Projects to Actionscript 3.

While I was writing the class, I decided to keep the option to skip some checks according the current settings, so I ended up using namespaces in a way that could be interesting for you as well.

When the DesignByContract class is used, the Check namespace must be imported as well. The DesignByContract classes must be used through this namespace in this way:

DesignByContract.Check::Require(1 == 0); //the assertion will obviously fail 🙂
DesignByContract.Check::Ensure(1 == 0);
DesignByContract.Check::Assert(1 == 0);
DesignByContract.Check::Invariant(1 == 0);

By default Check is set to CheckAll and this will enable all the checks in run-time. If you want instead to perform only the preconditions, it is enough to change the Check value inside the Check.as file to CheckPrecondition.

That’s it, short and easy. Check the code out at:


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