Matrox Design Assistant allows you set the lifetime of each
variable separately. You can establish whether a variable retains
its value between calls to its flowchart, and whether it retains
its value after your project is stopped.
When you add or edit a variable, you can set its lifetime. This
is typically established by its Reset Point and Persist value
properties.
Reset Point
is set to NeverReset by default,
indicating that the variable is static. Each time you call its
flowchart, the variable will retain its value from the flowchart's
previous run. You can also set Reset Point to
InspectionStart or FlowchartStart. This resets the variable to
its initial value at the beginning of the inspection or at the
beginning of the flowchart.
For example, consider a numeric variable named TheCount that is initialized
to 0 and defined in a subflowchart. TheCount is incremented by1
every time the main flowchart calls this subflowchart. If
Reset Point is
set to NeverReset, TheCount will remember its
previous value every time the subflowchart is called and correctly
track how often this happens. If Reset Point is set to
InspectionStart
or FlowchartStart, TheCount will be initialized
to 0 each time the subflowchart is called.
By default variables are initialized when you reset or restart
your project, regardless of their Reset Point. To retain a
variable's value across project executions, you must set the
variable's Persist
value property. For more information, see the
Persistence and the SavePersistentData step section in
Chapter 57: Persistence.