Extract all declared function names from header into boost.preprocessor

Question

I have a C header file containing various declarations of functions, enums, structs, etc, and I hope to extract all declared function names into a boost.preprocessor data structure for iteration, using only the C preprocessor.

All function declarations have two fixed distinct macros around the return type, something like,

// my_header.h
FOO int * BAR f(long, double);
FOO void BAR g();

My goal is to somehow transform it into one of the above linked boost.preprocessor types, such as (f, g) or (f)(g). I believe it is possible by cleverly defining FOO and BAR, but have not succeeded after trying to play around with boost.preprocessor and P99.

I believe this task can only be done with the preprocessor as,

1. As a hard requirement, I need to stringify the function names as string literals later when iterating the list, so runtime string manipulation or existing C++ static reflection frameworks with template magic are out AFAIK.
2. While it can be done with the help of other tools, they are either fragile (awk or grep as ad-hoc parsers) or overly complex for the task (LLVM/GCC plugin for something robust). It is also a motivation to avoid external dependencies other than those strictly necessary i.e. a conforming C compiler.

Answer 1

I don't think this is going to work, due to limitations on where parentheses and commas need to occur.

What you can do, though, is the opposite. You could make a Boost.PP sequence that contains the signatures in some structured form and use it to generate the declarations as you showed them. In the end, you have the representation you want as well as the compiler's view of the declarations.