Rust doesn't have varargs, so formatting functions tend to be macros (allowing to pass in multiple arguments, compile time parsing the format string to allow type checking etc) so they are generally not that trivial.
There are some examples of printing output using formatting strings in the RustCrypto readme:
let hash = Blake2b::digest(b"my message");
println!("Result: {:x}", hash);
If you're looking to get the actual string value rather than just print it out, then take a look at the format macro. It uses the same format strings / traits etc as println, so wherever you see println you could drop in format instead:
let hash = Blake2b::digest(b"my message");
let text = format!("{:x}", hash);
There are some examples of printing output using formatting strings in the RustCrypto readme:
https://github.com/RustCrypto/hashes#usageIf you're looking to get the actual string value rather than just print it out, then take a look at the format macro. It uses the same format strings / traits etc as println, so wherever you see println you could drop in format instead:
https://doc.rust-lang.org/std/macro.format.html