Progress
Programming
Handbook
Procedure Overriding
Progress supports a mechanism for overriding Progress internal procedures and user-defined functions. This accomplishes the following goals:
- Implementing a basic object-oriented programming principle of great value in designing Progress components that build on standard behavior.
- Replacing the dispatch mechanism, which the ADM of previous versions of Progress implemented in 4GL code. The new mechanism makes overriding procedures faster, cleaner, and completely transparent to callers, who can now invoke potentially multiple layers of application behavior by using an ordinary RUN statement.
Another term for this behavior is dynamic procedure scoping. Progress dynamically scopes the name space in which Progress searches for a procedure someone wishes to run, and extends that name space to more than one running procedure instance.
This section covers the following topics:
NOTE: For a complete description of the 4GL elements described in this section, see the Progress Language Reference .
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