[Pharo-users] [exercism bowling challenge] Is there a better way to do this

Hello, To come back at this one. I made a class Bowling and a class Frame which contains two instance variables named firstThrow and secondThrow. but I still wonder how do I know which one to fill in. I can do \` (firstThrow nil?) \` but that feels not right. \ Is there a more idiomatic solution for this ? Roelof