CppCon 2014: M. Juchem "Meta Techniques: Heterogeneous Polymorphism & Fast Prototyping at Facebook"

简介：

As data‑driven systems evolve, there is an ever‑growing demand for bringing new functionality into existing systems in an efficient, maintainable, and least intrusive manner. When implementing features with different semantics or interfaces, virtual inheritance requires a compromise between design simplicity and performance, implying a need for new techniques to achieve heterogeneous polymorphism efficiently. With C++11 and C++14, type lists, type maps, and variants can now be trivially implemented by the initiated. Facebook moves fast, so we quickly adopted the new standards to further explore the capabilities of the type system. This talk demonstrates meta‑programming techniques such as reflection and compile‑time built structures to achieve heterogeneous polymorphism and fast prototyping. Marcelo Juchem is a Software Engineer at Facebook, working in stream processing and spam‑fighting systems. Fascinated by template meta‑programming, he sees the C++ compiler as a powerful type juggler and programmable code generator. These capabilities allow the combinatoric composition of types into efficient abstractions, reducing code duplication and enabling non‑library writers to design logical component interactions and semantics rather than dealing with low‑level details.