使用 range-v3 构建无限范围

Question

I am trying to build a range which produces infinite random points in a triangle. To do that, I am using CGAL, which already provides the functionality to generate the random points in a triangle.

        Triangle coarseTriangle = {v[0], v[1], v[2]};
        CGAL::Random_points_in_triangle_2<Point> randomSamplesGenerator(coarseTriangle);

However, CGAL::Random_points_in_triangle_2 returns an iterator. In order to produce a range, I need a sentinel which always return false. Is there any sentinel like that already in range-v3 or do I have to code one myself?

Answer 1

You can use std::unreachable_sentinel (Or ranges::unreachable from <range/v3/iterator/unreachable_sentinel.hpp> ):

        ranges::subrange randomSamplesRange(randomSamplesGenerator, ranges::unreachable);