Reverting EyeInspector>>#updateList revealed the error when Phexample is used in latest Pharo 3.0... PhexMatcher uses #= as part of it's DSL e.g. "1 should = 1". Because it doesn't respond normally to #=, #hash is implemented to signal an error (self error: 'Don''t put a matcher into a dictionary. It does not behave ordinarily on ='). I guess the receiver inspector on the bottom left of the debugger keeps the items in a dictionary, so #hash gets called and everything blows up. The first thought that comes to my mind is that #= is "too cute" as a DSL. #= is too deep of a smalltalk concept to justify hijacking, AFAICT to avoid writing equals:. I removed #= and #hash from PhexMatcher, adding an #equals: with the former #= implementation, and everything seems to work. I don't have write access to http://smalltalkhub.com/mc/Phexample/Phexample/main/ and realize it's a big API change, so I committed the fix to http://smalltalkhub.com/mc/SeanDeNigris/SeansOutbox/main/ : Name: Phexample-SeanDeNigris.71 MAJOR API CHANGE: - change matcher #= to #equal: e.g. "1 should = 1" would now be written "1 should equal: 1" - update all code to use new API Motivation: the #= magic made it impossible to store matchers in dictionaries, and #hash was implemented to signal an error explaining as much. Unfortunately, #= and #hash are deeply ingrained Smalltalk concepts, and are assumed to work as expected. In Pharo 3.0, the debugger tried to put matchers in a dictionary, causing an infinite error loop whenever a matcher failed. ----- Cheers, Sean -- View this message in context: http://forum.world.st/Phexample-API-Change-Proposal-was-Phexample-Image-Dest... Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com.