Hi - I have a subclass of ComposablePresenter (lets call it MyPresenter) that seems to work how I want. When doing some processing I'd like to open MyPresenter when an exception occurs and pass it the exception e.g. [ [self testCondition] whileTrue:[ self doSomeStuff] ] on: MyNotification do:[:ex | self openMyPresenterWith: ex] But that just results in lots of MyPresenter windows opening while the execution of the #whileTrue: loop runs its course. How do I pause the loop so I can use the MyPresenter window to modify and fix the condition that raised the MyNotification? The MyPresenter window just edits the contents of a couple Dictionaries so isn't too tricky but it isn't really as easy to do in a debugger as it is clicking a radio button and a "do it" button. Thanks