Mathias Gaunard wrote:
David Abrahams wrote:
Hi Neil,
I'm sure someone already spoke to you about this, but just in case: Andrei Alexandrescu gave a very interesting presentation at BoostCon that was based on a "ranges only" approach that should eliminate issues like this one:
2: return type specification for find() etc =========================================== There where no major objection to the mechanism, but some found the syntax ugly. I believe the suggested syntax (e.g.)
boost::find[_f,_e]( range, x )
boost::find[_f+1,_e]( range, x )
He says he's implemented a superset of the STL algorithms with it so we know the expressive power is fairly complete. I was wondering if you had given any thought to making use of his insights? Especially considering that RangeEx hasn't been used to fully cover a generic domain (I think), it might make sense.
First-class ranges would still need to be convertible to iterator pairs, since iterators are useful on their own as a mean to express positions.
That would limit ranges because there are ranges that are not pairs of iterators.
For example, let's say I write a simple algorithm that takes three bidirectional iterators: the begin of the sequence, the end of the sequence, and a position anywhere in between. That algorithm then returns whether the position in between lies on a word boundary by reading what is left and right of it.
How would I express such an algorithm with ranges only?
You would pass two adjacent ranges, like D's bringToFront (a generalization of STL's rotate, see http://www.digitalmars.com/d/2.0/phobos/std_algorithm.html) takes. Andrei