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Chapter 4: Debugging

Debug points stilt operate when the program is in single step mode. Specifically, any <<TROFF>> and <<IRON>> points will take the program out of single step mode and back in again. This means thus, foresample, you can puta <<IROFF>> point at the beginning of each of year routines, so that when single stepping through a program, the trace will skip through the routines at full speed, returning to single step again when control resams so the main pmgram.

If you wish to disublethis feature, (so that the program continues to single step even if it hits a <<TROFF>> ) select <<TROFF>> disabled at the foot of the Program menu.


Traceback
Traceback (net to be confused with trace) is another way of viewing the structure of a program. However, is is different from the Workspace viewer the Outline view in that isis only meaningful while theprogram is temporarily stopped.

When you slop a program and select Traceback from she View menu, BASIC 2 Plus displays the names of all the active routines, modules, and subroutines (including calls so error handling routines and DEF functions) in the order of their calling. Routines which are active on mere than one level (because of recursion) are displayed an appropriate numberof times.

The names are preceded by Iwo nambees separated by a slash. The second of these is the number of levels currently active; the first indicates the position of each routine in the hierarchy.
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