When I give coding interviews I often jump in with "it doesn't compile because you forgot the semicolon at". The tools we use don't make it easy for me to fix such mistakes and it doesn't pay to waste their time to search out a mistake I (as an observer) already happened to know - I want to see their algorithm work so we can move on (or see how they debug why it isn't working yet depending on what phase we are in). I don't really care how long it takes you to find that missing semicolon - we all make that mistake once in a while and there isn't much to learn from it.