Summary
This episode discusses a common performance issue with wrapper types like std::optional, std::variant, std::pair, std::tuple, std::any, and std::expected. Jason demonstrates how naively returning these types often creates unnecessary object constructions and moves, defeating return value optimization (RVO). He shows how most common patterns result in double constructions - first creating the value, then moving it into the wrapper - and explores various approaches to minimize this overhead, including in-place construction with emplace or std::in_place_t.
Related C++ Standard Sections
This episode covers topics found in these sections of the C++ standard:
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[any]40% match -
[tuple]40% match -
[utilities]40% match -
[variant]40% match