/*
 * Key idea:
 *
 *   In C++14 we can omit the trailing return type, leaving just the leading
 *   auto.
This is a good thing, because it means that the return type is
 *   automatically deduced from the function signature.
 *
 *   In C++11 we can omit the trailing return type, leaving just the leading
 *   auto.  This is a good thing, because it means that the