Question arising from the FAQ: 7.4 says: We recommend that predicate methods (those whose name ends with a question mark) return true or false. Other methods that need to indicate failure should return nil. While we are unloading the multiple meanings of nil (or like 0 in C as null and false and... :) shouldn't we do it to the full extent at once by introducing FailureClass and mentioned routines should return a failure (instance FailureClass). Then nil would have only (?) the meaning undefined or unspecified. - Aleksi