CLISTs that are structured applications

The CLIST language includes the basic tools you need to write complete, structured applications. Any CLIST can invoke another CLIST, which is referred to as a nested CLIST. CLISTs can also contain separate routines called subprocedures. Nested CLISTs and subprocedures let you separate your CLISTs into logical units and put common functions in a single location. Specific CLIST statements let you:

Define common data for subprocedures and nested CLISTs
Restrict data to certain subprocedures and CLISTs
Pass specific data to a subprocedure or nested CLIST

For interactive applications, CLISTs can issue commands of the Interactive System Productivity Facility (ISPF) to display full-screen panels. Conversely, ISPF panels can invoke CLISTs, based on input that a user types on the panel. When the user changes a value on a panel, the change applies to the value in the CLIST that displayed the panel. With ISPF, CLISTs can manage extensive panel-driven dialogs.