Parser Combinator

Hello, everyone. I am learning Rust and I am working on a parser combinator library for strings to which I'd really appreciate some recommendations, advice and code review.

Thank you very much!

Link: GitHub - oebelus/parsenator: Trying to implement a basic parser combinator for strings

It's a really interesting. I enjoyed reading your code. But I prefer something simple. For example, why Left and Right may hold different types? Why you have a lifetime qualifier for every structure? If you do a parser, usually it's okay all your structures have a static lifetime. Anyway, thank you for sharing your work.