Peano

Peano is a library for type-level numbers in Rust. It has been supplanted by typenum, which does the same things (and more) and is much faster.

The advantage of peano is that it is much simpler; the entire library is a single file that is under 400 lines of code, many of which are comments.

So, take a look if you want to explore type-level programming. If you want to import a library, use typenum.