This is part 2 of a tutorial on Void safety, the Eiffel mechanism that removes the risk of null pointer dereferencing (crashes due to calling an operation on a non-existent object). This video introduces a key mechanism: object test, which lets you apply an operation safely to an object, guaranteeing that the object exists. You should first have watched part 1, which you can find at • Void Safety in Eiffel, Part 1: the end of ... .