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
template<typename List, bool Empty = IsEmpty<List>::value>
class LargestTypeT;
// recursive case:
template<typename List>
class LargestTypeT<List, false>
{
private:
using Contender = Front<List>;
using Best = typename LargestTypeT<PopFront<List>>::Type;
public:
using Type = IfThenElse<(sizeof(Contender) >= sizeof(Best)),
Contender, Best>;
};
// basis case:
template<typename List>
class LargestTypeT<List, true>
{
public:
using Type = char;
};
template<typename List>
using LargestType = typename LargestTypeT<List>::Type;