Making Iterators, Views and Containers Easier to Write with Boost.STLInterfaces - Zach Laine CppCon

cppcon.org/
github.com/CppCon/CppCon2020/...
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Writing standard-compliant iterators is surprisingly easy to get wrong. Standard containers are tedious to write, because they have such large interfaces, involving lots of similar operations. For many years, Boost.Iterator's iterator_facade and iterator_adaptor were the state of the art for automating the creation of iterators with minimal effort. However, that library has not kept up with the evolution of C++, particularly with regard to constexpr and noexcept.
Boost.STLInterfaces is a newly-accepted Boost library that solves these problems for authors of iterators and sequence containers. It does this using the same approach as C++20's std::ranges::view_interface. The view_interface template is a CRTP base that implements all the possible view member functions when inherited by a derived type containing just begin() and end(). This pattern allows the user to use Boost.STLInterfaces to write correct iterators, views, and/or sequence containers, requiring surprisingly little code.
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Zach Laine
Sr. Principal Software Engineer, Cadence Design Systems
Zach Laine has been using C++ in industry for 15 years, focusing on data visualization, numeric computing, games, generic programming, and good library design. He finds the process of writing bio blurbs to be a little uncomfortable.
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[@keris3920]

Brilliant. Interface/contract-based programming makes implementation much easier on on newcomers, which is something I think the could improve on. Consider me an adopter.

[@peepzorz]

@7:40 For your comparison operators = , is there a good reason to also call operator== ? I would think its more efficient to just logical negate the "opposite" operation, so only operator< is required for those. Like this (hopefully youtube comment doesn't mangle code paste here):
operator() { return rhs < lhs; }
operator rhs); }
operator>=() { return !(lhs < rhs); }