Enum

[skynowa]

• brief const type for enums
• operator << ()
• toString()
• fromString()
• asString()
• size(), begin(), end() - for(;;)
• isValid()
• --/++
• https://github.com/Neargye/magic_enum (C++17)
• https://stackoverflow.com/questions/28828957/enum-to-string-in-modern-c11-c14-and-future-c17-c20
• https://sourceforge.net/p/my-gui/code/HEAD/tree/trunk/MyGUIEngine/include/MyGUI_ResizingPolicy.h
• https://crascit.com/2015/01/14/iterating-over-an-enum/