When you set a checkpoint in a script, HyperCard will enter its debugging environment at that point when the script is run. It will pause in its execution of the script, display the script in a window, display the Debugger menu (shown above), highlight the next line of the script to be executed, and display the Variable Watcher (which you will soon see).
Click on the options in the Debugger menu to learn about them.
-- part contents for card part 4
----- text -----
The step option takes you to the next line in the handler.
-- part contents for card part 5
----- text -----
Step Into steps into and follows the trail of subhandlers.
-- part contents for card part 8
----- text -----
Trace traces a handler to its completion.
-- part contents for card part 10
----- text -----
Go sets the handler running again, until its completion.
-- part contents for card part 11
----- text -----
Clear Checkpoint option clears the current checkpoint.
-- part contents for card part 13
----- text -----
Abort is the same as command-period: it stops the execution of a handler.
-- part contents for card part 16
----- text -----
The last two options allow you to show and hide two tools for seeing the functioning of your scripts—you’ll see them shortly.