christopher diggins wrote:
----- Original Message ----- From: "Jonathan Turkanis"
void ToUpper() { char c; while (cin.get(c)) cout.put(c); }
I don't see why this is better than
struct toupper_filter : input_filter { template<typename Source> int get(Source& src) { return toupper(boost::io::get(src)); } };
and its cousins.
Then that pretty much closes the discussion. If you do not see the benefits of the lower complexity, then there really is little more I can do to convince you otherwise.
It's not that I don't see the benefit of lower complexity; I don't really see the lower complexity. ;-) The only noticeable difference is that mine contains "template<typename Source>" and uses a non-member get function. Your version requires that an entire stream of data be processed at once -- leading to poor memory use -- and doesn't work at all for streams which have no natural end. To justify this I'd like to see something more substantial that the elimination of "template<typename Source>".
int main() { fstream("input.txt") > Filter(ToUpper); }
This won't work, since fstream("input.txt") produces a temporary object which cannot be used to initialize a non-const reference. Therefore operator< would have to be declared to take a const reference, and the non-const extraction functions would not be usable.
I already made it work by creating temporary helper objects which take the address of the temporary objects.
The Boost.Iostreams solution (if I add your extension to the |-syntax) is as follows: file("input.txt") | toupper_filter() | ref(std::cout); This seems very elegant to me. I don't see any reason to make the reference to std::cout implicit. In fact, I think it would make the above more difficult to understand. Jonathan