I think that some amount of knowledge was assumed. You would have understood it if you had known Java. For-each loops in Java have a very similar syntax. You p

I think that some amount of knowledge was assumed. You would have understood it if you had known Java. For-each loops in Java have a very similar syntax. You probably know something that is similar to Ruby, and that's why you understand it without ever learning it. I bet that you wouldn't understand it if you didn't know any programming language at all.