...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards
...one of the most highly regarded and expertly designed C++ library projects in the world.
#include <boost/hof/identity.hpp>
The identity function is an unary function object that returns whats given to it.
identity
assert(identity(x) == x);
template<class T> constexpr T identity(T&& x);