CppCon 2020

One of the hallmarks of "modern C++" is a transition from classic object-orientation to value semantics with algebraic data types such as `variant` and `tuple`. In this session we'll explain the math behind the name, and we'll delve deep into the meaning and usage of all of the algebraic data types in C++17: pair, tuple, optional, and variant. These types have some commonalities, such as the use of type-traits to access their component types, and a common approach to implicit conversions and comparisons. We'll show how to use std::optional for deferred initialization and how to replace dynamic polymorphism with visitation over a std::variant. We'll even deliver some guidance on when NOT to return a tuple, and on how you should think about variant's "valueless by exception" state.
Attendees will leave this session with a newfound appreciation for C++'s algebraic data types.