I was reading the documentation for std::io::BufReader ( https://doc.rust-lang.org/std/io/struct.BufReader.html ). My problem is this example is so short it doesn't really show how to pass a BufReader to a function. The type is never actually given explictly (there is a magical "R", which is never given), so I wasn't clear how to actually pass it around.
I eventually found a stackoverflow answer which talks about BufRead, although then I was later confused that I couldn't find BufWrite.
I was going to make a github issue, and maybe even try a PR, but I wondered if there should be more discussion first about the right way to tackle these things.