The following code example is taken from the book
C++ Templates - The Complete Guide, 2nd Edition
by David Vandevoorde, Nicolai M. Josuttis, and Douglas Gregor,
Addison-Wesley, 2017
© Copyright David Vandevoorde, Nicolai M. Josuttis, Douglas Gregor 2017
#include "isconvertible.hpp"
#include "enableif.hpp"
#include "lessresult.hpp"
template<typename T>
EnableIf<IsConvertible<LessResult<T const&, T const&>, bool>,
T const&>
min(T const& x, T const& y)
{
if (y < x) {
return y;
}
return x;
}