On Mon, Jan 30, 2012 at 9:30 AM, Roman Perepelitsa <roman.perepelitsa@gmail.com> wrote:
2012/1/30 Beman Dawes <bdawes@acm.org>
One of my blink reactions is that array_ref<T> and basic_string_ref<charT, traits> are range generators and I was a bit surprised to see the implementation was a pointer and length rather than two pointers.
Implements are free to use two pointers if that's faster on some platform.
Sure.
Or better yet, two iterators or an explicit range component. With iterators, a basic_string_ref could do encoding conversions on-the-fly without need of temporary strings. But I have no idea if that is workable or actually is better.
I don't see how this could work unless each access to basic_string_ref involves a virtual function call or all functions accepting basic_string_ref must be templates. function that accepts a range of integers, you either have to implement it as a template or use any_iterator/any_range which could be too inefficient.
The other alternative is to use the boost::filesystem::path/N3336 approach, which avoids conversion inefficiency if no conversion is necessary, but does come at the cost of creating a temporary when a conversion is required. Anyhow, that's all an aside to the real questions: What are the pros and cons of N3334 in general and basic_string_ref in particular? Thanks, --Beman