ENHANCED GRAPHICAL DEVELOPMENT ENVIRONMENT FOR CONTROLLING PROGRAM FLOW

A graphical development environment for developing the program flow of an application. The environment represents the program flow as an arrow between starting and end points. A developer can modify the program flow by adding an icon representing a subroutine to any point on the arrow. Loops and possible returns of a subroutine are graphically represented by the environment. If the developer modifies the API of a subroutine, the environment graphically represents the calling routines that are affected by the API change. The environment also allows functional components of subroutines to be overwritten by the caller. In such a case, the overwritten components are executing within the caller's environment space. Different overwritten instances of an overwritable subroutine may exist in the same program flow.