PackCC a PEG parser generator for C (Single source file) (github.com)

It has a little bit more options than greg, but I don't see its use-cases yet.

I give this project an A+ for presentation. Great examples.

If all software projects provided examples with "input.txt" and "expected.txt", then the world of programming would be a better place indeed!

Alas, packrat is only potentially useful to me for small input. It requires an amount of memory equal to the size of the input. I have memory resource contraints.