# Error Handling
When sending a submission to the dropbox, it's very important to provide feedback to the student. They should know if the submission went through successfully.
Submitting with the `Submission::submit()` function returns a `Result` that you can use to handle any possible errors. The `Err` variant of the `Result` is a [`reqwest::Error`](https://docs.rs/reqwest/0.10.7/reqwest/struct.Error.html).
```rust
// some code omitted
fn main() {
// Open the dropbox somewhere else
dropbox::open_with_arg("open_sesame", 8080);
let mut sub = Submission::new();
// Grading, etc goes here...
// using `match` gives us basic error handling.
// here, we're just printing the error. This can give more insight
// as to what went wrong.
match sub.submit("http://localhost:8080/submit") {
Ok(_) => println!("Submission recorded!"),
Err(e) => println!("Error! Couldn't record submission.\n{}", e);
}
}
```