optional

Optional

Here we explore:

• how std::optional offers an alternative to errors codes and exceptions.
• how the insertion of a std::optional affects following functions.

Prerequisites

• slides about std::optional

Instructions

In the file optional.cpp, modify the function mysqrt below so that it returns an std::optional<double> rather than a double, and the program prints nothing rather than nan for the call with -10. It will also require to modify square.