https://www.youtube.com/watch?v=VhIwDxkIsMEExpression templates are very useful, but also come with a high implementation and maintenance cost, even when using a library like Boost.Proto. With the newer C++14 and later features, most notably generalized automatic return type deduction, it is now possible to make an expression template library with low compile times, high ease of use, and good object code generation.
Yap is an expression template library being proposed for Boost. It uses Hana, C++14, and C++17 (optionally) to make expression templates very easy to read, write, and use. This talk will be about using Yap, the process of creating Yap, and lessons learned using the new C++14 and C++17 features.