With this capability, you can quickly generate applications and test them in a live situation. The resource editor itself is flexible and provides functionality not available in other interface builders. In defining a menu, for example, you can set menu-item colors, define an arbitrary marking character, and provide an icon on the item line. At the bottom right of the definition dialog box, you can see the routine that is executed whenever the menu item is selected. You change it by simply pressing the routine button and selecting another function.
Similar capabilities exist for window and dialog-box designs.
It interprets this intermediate language when you run the application. You can also build stand-alone applications that use the interpreter, thereby ensuring that your final applications run precisely the same code as they do in your development environment. One advantage is that the interpreter usually maintains a lot of information for decoding and displaying complex data structures. The VIP interpretive environment also ensures that programs don't exceed defined array bounds. It also contains several advanced features, such as the abilities to continue execution until a Boolean expression is true, alter variable contents, and continue execution until the program returns from the current function.