Mission Impossible / How to create datatypes which cannot contain invalid state

Create datatypes which do not allow invalid state

Many user defined datatypes created in "classical" C++ allow many states which should not happen in production.

This playground has the goal to show some of them and how to avoid them using C++14/17 standard library type additions.

The build environment is:

• Clang 7.0.1
• -std=c++17
• -Wall -Werror
• Libraries: Boost 1.68

Disclaimer

This playground was written for a C++ Usergroup session (https://cpp-ug-luzern.blogspot.com/). It may not yet be ready to use without further context.