Cpp17 to Cpp20 transition

The project is currently developed for C++17. Here are listed some major parts of the codebase which should be modified when C++20 starts to be utilized used.

  1. Add hierarchy to parser’s syntactical structure (that is expression, statement, etc.) using cpp20’s <concept> in order to mark their specific “type”.

  2. Use <format> for string formatting.

    • Error reporting