refactor: use nullptr

[e-kwsm]

pugixml/CMakeLists.txt

Lines 71 to 79 in 9d7fcbf

	# Set the default C++ standard to C++17 if not set; CMake will automatically downgrade this if the compiler does not support it
	# When CMAKE_CXX_STANDARD_REQUIRED is set, we fall back to C++11 to avoid breaking older compilers
	if (NOT DEFINED CMAKE_CXX_STANDARD_REQUIRED AND NOT DEFINED CMAKE_CXX_STANDARD AND NOT CMAKE_VERSION VERSION_LESS 3.8)
	set(CMAKE_CXX_STANDARD 17)
	set(CMAKE_CXX_STANDARD_REQUIRED OFF)
	elseif (NOT DEFINED CMAKE_CXX_STANDARD)
	set(CMAKE_CXX_STANDARD 11)
	endif()

C++11 or later is necessary, so nullptr must be available.

[e-kwsm]

Thank you for your review. I understand your point.
But 0/NULL, instead of PUGIXML_NULL, are used for nullptr, which is fixed in d74511c.

Would you reopen this? I will revert the other commits.

[zeux]

But 0/NULL, instead of PUGIXML_NULL, are used for nullptr, which is fixed in d74511c.

This is by design, you can refer to other PRs around NULL replacements. I'm not interested in further changes in this area.