What's the c++ standard version (like 17/20/23) should I use for swift/c++ clang module?

Using Swift
1

or any place to set the c++ standard?

2

At the Package level (in Package.swift), you can use the property

cxxLanguageStandard: .cxx20

for example. You can also set the standard at the target level, but I forgot where exactly. probably in the cxxSettings.