It's funny because i actually did exactly what you're talking about once when I ran into a bug in the parsing logic of wikitext tables in pandoc. I read the (extremely well organized) source, having never ever done any haskell before. The fix ended up being a 2 character change, it took me an hour to do, and I didn't really have to learn haskell to do it.

Point being, if you find a bug in a software, as a fellow developer, I think it's reasonable for the maintainer to expect you to at least take a quick look around. Regardless of prior knowledge. You get to learn stuff, and the project maintainers have their load lighten up.