Seen on this site, the code shows macro invocations using a tilde in parentheses:
HAS_COMMA(_TRIGGER_PARENTHESIS_ __VA_ARGS__ (~))
// ^^^
What does it mean / do? I suspect it to just be an empty argument, but I'm not sure. Is it maybe specific to C(99) like the __VA_ARGS__ is specific to C99 and existent in C++?