“Initializer lists” are just horrible kludges.
Don’t:
#include <initializer_list>
template<typename T>
void Dont(std::initializer_list<T> list) { // Bad!
static_assert(list.size() == 3, "Exactly three elements are required.");
}
void Test() { Dont({1,2,3}); }
Do:
template<typename T, std::size_t N>
void Do(const T(&list)[N]) { // Good!
static_assert(N == 3, "Exactly three elements are required.");
}
void Test() { Do({1,2,3}); }