I've fixed it. Looks like a lot of the code, but not all, had been auto-formatted. I didn't consciously do it, but I may have fallen asleep while coding and mashed some keys. I'm getting up early (4am) so coming home on the train at 6:00pm is pretty sketchy :-) I pulled the code into a new image from the changes file, which fortunately did not include the formatting, so could copy back the original code into my broken image. Once complete everything works again.
-- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html
