On Wed, 05 Jul 2006 22:01:55 +0800 Joel de Guzman <joel@boost-consulting.com> wrote: Joel, I am really interested to know why you prefer the functional approach in C++, a language which offers both options.
Me, I prefer the immutable and functional approach:
to_upper(to_lower(to_upper(rng)))
Blech. What are the overwhelming reasons for having purely immutable interfaces in C++? If I had both mutable and immutable options available to me, there is no way I'd use the above, unless there was a very good reason. In most cases, "++i" may not be much better that "i++" but I always prefer "++i" unless I have a very good reason for the other option. Sure, premature optimization is bad, but premature pessimization is worse. If you have two readily available and similarly easy to use interfaces, why would I want to use the one that incurs far more overhead? I assume you will answer that you'd prefer to only have the immutable interface available, so, whay is that, particularly in C++?
For the record, I don't like fat everything-but-the-kitchen-sink interface too. Same as I dislike mutating functions. Sorry, Jeff.
I'm not in favor of huge interfaces either. However, let's not forget that just because a function is outside the class specification, does not remove it from the class interface.