Yep, you can only access a variable inside a function if it was declared inside that function, or if the function ```uses```es that variable in its declaration. Or use global, but yuck.

TBH I'm not sure what the difference is between ```global``` and ```use```. Can't find much in the docs. I think global is old and use is new.

And as for the nested functions, returning a value is entirely optional, depending on the contract of the function. For this simple example, I'll leave it out.

Having said that, I haven't mentioned the return statement for functions anywhere. I'll add that to the todo list.