Compiler errors with E0135.

[Jarsergej]

when i comp code with library, it's always shows me a lot of mistakes. Why is it so? Help pls!

[HexDecimal]

The latest versions of Libtcod require C++17. This means compiling with /std:c++17 or later, and using Visual Studio 2017 or later, when using the Windows toolchain. Without C++17 important templates like std::optional will be missing.

Update to the latest Visual Studio and then tell it to use the /std:c++17 or /std:latest flags.