In-Place Construction for std::any, std::variant and std::optional--Bartlomiej Filipek
Efficient construction.
In-Place Construction for std::any, std::variant and std::optional
by Bartlomiej Filipek
From the article:
When you read articles or reference pages for std::any, std::optional or std::variant you might notice a few helper types called in_place_* available in constructors.
Why do we need such syntax? Is this more efficient than “standard” construction?

Have you registered for CppCon 2018 in September?
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