Having to go to docs.rs and look up the method rather than being able to do `perldoc [package]', or (even better) being able to just ask your language to `(describe '[method])' is terrible.
You can do that (depending on your editor) and you can follow the types around. But many times I find myself preferring docs.rs for documentation navigation.
cargo doc --open gets you a web browser pointing at local documentation for exactly the set of stuff in your installed versions of all crates for the current package.
