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Comment by DubiousPusher | Hacker News Reader

Has there been any notion of a replacement Meta/Macro language for C? Something open source. Of course pre-preprocessing one's files and the complexity that might add to the build system are unattractive but I'd still be interested if someone has attacked this problem.

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Much of what makes 'C' annoying can be made less painful by referring to static/const struct tables/arrays. Those are a prime candidate for generation.

You don't have to keep the preprocessing of files as part of the mainline build, but there's something to be said for it - sort of "make GENERATE_ALL_THE_THINGS" might run the preprocessing { Python/Tcl/Perl/bash/even 'C' } scripts for you.

If the generators just emit .h files, that can be pretty good. You're still left with something #ifdef-ey to select them, based on #defines or -D options.

You might even go so far as to dynamically load these tables if that can make sense. The ld linker can directly link in blobs.

The module and template features (along with static if, if the committees figure out what to do in that area) in the newest versions of C++ together get pretty close to replacing the C preprocessor.

Static if can be ( crudely ) synthesized today.

My school of thought would be to limit it to just #include, #if, #else, #end, and non-recursive single word only #define / #undef. Force everything to be 1 per single line, and call it a day.

Macros should always be the absolute last resort to doing anything. Stepping through code in gdb with some "creative" macro-based API is almost as bad as C++.

I've seen 'C' macros used to do template-ey things that probably reinforced the readability of the code ( once you get used to the fact that the macros were there at all ) .

More modern compilers allow using non-static "const" constructs to do much of the same, which is a great improvement.

To wit:

#define in_bounds(lower,x,upper) ((x <upper) && (x >lower))

vs. const bool in_bounds = ((x > lower) && ( x < upper ));

Macros can be used effectively for reduction in strength, so long as you're not too clever about it.

You'll forgive me if my knowledge is a bit dated. I largely work on tools integration these days and don't do much in the way of framework development but aren't macros pretty much the defacto way of doing reflection/rtti. Actually, almost every mature framework I've worked with in the past used macros to markup class properties, register types, etc.

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