> How is "opt-out option types" different from, say, Java, where everything is nullable and all the problems that come with that? Aiui the Java compiler and la

> How is "opt-out option types" different from, say, Java, where everything is nullable and all the problems that come with that? Aiui the Java compiler and language constructs generally don't know the difference. The P6 Nothing isn't a null, it's a "type object" with memory- and type- safe behavior. There's a tiny bit more about this at: https://en.wikipedia.org/wiki/Option_type#Perl_6 https://en.wikipedia.org/wiki/Option_type#Perl_6