I have an improvement suggestion: add #define to the preprocessor commands and let it work like %define.
The reason why I want this is becuase GCC supports #define keyword value but nasm can only (?) handly %define keyword value. By changing this one can have the same "define"-files in both nasm and GCC thus only one config file is needed.
I would be glad if one of the nasm programmers could tell if this is possible to implement.