A more useful "so you think you know C?" is this test: Write a variadic macro `CLEANSE_MACRO_ARGS` that can be used within one of C's unhygienic macros, to tur

A more useful "so you think you know C?" is this test: Write a variadic macro `CLEANSE_MACRO_ARGS` that can be used within one of C's unhygienic macros, to turn it into a hygienic macro without reducing the prettiness of the macro body. In standard C, this requires C23 and only works for macros that are not used as expressions. Or you can use GNU extensions and make it work for expressions and work even on old compilers.