Hi list, in the most recent dev image (9.10.5), OCompletion is broken for me. I lost my reproducible test case, but the gist was that sometimes when OCompletion had no idea which type a temporal variable would be, you were unable to insert code behind that variable, because if you tried, a debugger would show up. The problem appears to be Debugger>guessTypeForName:. debuggerMap can be nil and if it is, the method fails. I changed the method to the following, and then the strange errors that occur on my image disappear: guessTypeForName: aString | index object | index := debuggerMap ifNotNil: [(debuggerMap tempNamesForContext: self selectedContext) indexOf: aString ifAbsent: []]. object := index ifNil: [index := self receiver class allInstVarNames indexOf: aString ifAbsent: []. index ifNil: [^ nil]. self receiver instVarAt: index] ifNotNil: [self selectedContext tempAt: index]. ^ object class Essentially, I leave index at nil, if debugerMap is nil. I don't know enough about OCompletion to tell whether this is a fix, or makes things worse somehow. Cheers, Niko