Hi Stuart, thanks for explaining.
> ... After having looked at lots of generic APIs, it seems to me that a > style has emerged where wildcards are used whenever possible, and type > parameters are used only when necessary, ... Yes, I'm familiar with that kind of reasoning (I think Josh Bloch stated that principle in "Effective Java"). But, to be honest, I never thought that it should apply as a strict rule in all circumstances. Rhetorical question: do you really think that a signature employing 3 wildcards is easier to understand for the proverbial "average Joe" than a bounded type parameter that expresses the sub-type relationship clearly? I do not. But anyway, you probably have to follow the established "style". It's just too bad that most Java programmers I know won't understand the proposed signature of 'flatMap'. Kind regards, Stefan
