Tutorial: Jigsaw using ActionScript 3.0.

The constructor function Piece includes a statement that adds the newly constructed
Piece object to this array. The buildit, mixup and checkit functions make use
of pieces.
Class definitions are contained in packages. Specifically, each class definition is in its
own file and the contents of the file are
package jigsaw {
class Piece {
…
}
}
The example here has just one class and, therefore, just one file: Piece.as. It MUST
go in a folder named jigsaw and I placed it in a folder I named as3 directly in my C
drive. See below concerning the specification of the classpath that indicates to the
Flash environment where the packages are located.
The code interprets the key stroke event using built-in variables.
Implementation
You need to prepare two files for this application: the .fla file and the .as file that
holds the package that holds the Piece definition. The name of the .as file must be
Piece.as. It needs to go in a folder with the same name as the package, namely
jigsaw, and the jigsaw folder must be in a folder named in the classpath list. I
will give instructions on this later.
Start by opening up the Flash environment, under Create New, click on Flash File
(ActionScript 3.0)