The Best Type Traits that C++ Doesn't Have

Explore the intricacies of C++ type traits in this comprehensive conference talk from C++Now 2018. Dive into three proposed type traits that could enhance C++ functionality: is_trivially_relocatable_v, is_trivially_equality_comparable_v, and tombstone_traits. Examine how these traits can optimize operations like vector resizing, hash-table rehashing, and compare-exchange on atomic. Analyze benchmarks demonstrating performance improvements, particularly for vector operations. Discover how the introduction of "operator spaceship" in C++2a impacts trivial comparability. Learn about the concept of "tombstone traits" and how they can expose spare representations in types like bool and reference_wrapper. Gain insights into implementing these traits in library classes such as optional and cuckoo_hash. Follow along with code examples, benchmarks, and in-depth explanations of the design criteria and potential compiler support for these proposed traits.