Overwrite cmake flag CMAKE_CXX_STANDARD

[DmitryKuznecov]

I started using your library in my c++20 project and found behavior that I didn't expect.

I set the c++20 standard as
set(CMAKE_CXX_STANDARD 20).
Then, in one of the libraries, I include h5pp
find_package(h5pp REQUIRED).
After that, the standard is reset to 17, which I can observe
message("CMAKE_CXX_STANDARD ${CMAKE_CXX_STANDARD}") #print CMAKE_CXX_STANDARD 17

It's not very critical and I can set the c++20 standard manually again

[DavidAce]

Thanks for reporting this, it is certainly not the behavior I intended.
I think I have found the cause here. This file is installed and run as part of find_package(h5pp) which calls h5ppConfig.cmake. I'll try to encapsulate or avoid this line if possible.