You placed return in a separate statement, so your cell always returns, regardless of the if() condition. The condition now only controls whether a value will be yielded before returning.

Thanks! I see how that works. (the while loop is never reached, regardless of the condition). So I shouldn't have taken @Bergi literally https://stackoverflow.com/questions/42309185/js-generators-how-is-return-yield-different-from-yield/42309270?noredirect=1#comment131650087_42309270

1. You can return and yield in the same statement: `return yield j;` 2. Wrapping the loop in the else block is unnecessary, since your code will always return if the condition applies.

Thanks @Fabian! I see what you mean, I'm updating the Notebook to explain how... 1. `return yield j;` is used **because it is a single statement** (and `return` **stops the flow of function** ), (not used because of `yield` substitution, not depending on the actual return value) 2. Correcting myself, the else statement isn't necessary (but could be used *instead* of return statement, because it also stops flow of function from reaching infinite-while)