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VisualWorks Data Loss Prevention
How to Recover From Disaster
By Nicholas Bundy This is a guide on how to recover from various mishaps and disasters that can prevent you from saving your work.
Infinite Exceptions
An (almost) never ending nightmare So you’ve written your code, and you open your windowSpec to test it out, and you’re suddenly hit with a never ending stream of exception windows! As your memory runs out and your computer slows to a crawl because VisualWorks is using almost 100% of your CPU’s processing power to generate these exception windows, you fear that you’re going to have to terminate VisualWork’s process and lose all of your hard work. Fear not! VisualWorks has a special way for you to end this terror. First, press ctrl-\ (This may be the Apple key on Mac). This does two things. First, it brings up VisualWorks process monitor (kind of like Windows Task Manager, but for Visual Works), but more importantly, it halts the execution of the rest of the program, stopping those annoying exceptions from popping up.
From this Dialog, you can select certain processes to run or terminate. If you want, you can un-pause the main window and save your image, but you probably don’t want to save all these exceptions into your image. Believe it or not, you don’t actually have to do anything at this window. Just close the Process Monitor and the exceptions will stop, allowing you to debug or save your work. I’m not sure why, but this seems to break VisualWorks out of its infinite loop. If for some reason this doesn’t work, you can terminate the exceptions and the application you’re testing instead. Make sure to click the ‘Stop’ button on the Sample control, to stop it from checking for new windows and processes (the context menu counts as a process). Then, terminate the processes by right clicking on them and selecting terminate from the context menu that pops up.
If I Were a Painter
I would use the GUI painter While using the canvas Editor, you may have noticed that sometimes the GUI Painter Tool stops responding. There is an easy fix for this. First, close the GUI Painter Tool. Then, select the canvas you would like to use the GUI Painter Tool on. Then select the edit menu on the Palette window, and reopen the GUI Painter Tool from there.
Simply select "Replay->All from Top" to restore all of your changes. Then just twiddle your thumbs as your changes are restored. Occasionally, some exceptions might be thrown, but most of the time these are related to the Workspace, and not the saved code. Simply skip over these steps, and resume restoring.
