If you run this

use std::fs::File; pub fn main() { let fp = File::open("test").unwrap(); }

You get this:

thread 'main' panicked at /app/example.rs:11:33: called `Result::unwrap()` on an `Err` value: Os { code: 2, kind: NotFound, message: "No such file or directory" } note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

The language incentives you to propagate errors up to main and then just let it fail.