【笔记】Rust的错误处理

Preface

Notes on error handling in Rust

Classification of Errors

• Recoverable errors, can be caught and handled
• Unrecoverable errors, will cause the program to crash and cannot be caught

Throwing Exceptions

<err>: The error message

panic!("<err>");

Handling Exceptions with unwrap Function

• The unwrap function is a method of the Result enum
• The Result type has two possible values
  • If the value is Ok, it returns the object inside Ok
  • If the value is Err, it will throw a panic during runtime, with the parameter of Err as the argument to panic

fn function_name() -> Result<bool, String> {
    return if true {
        Ok(true);
    } else {
        Err("<err>".to_string());
    }
}

fn main() {
    function_name().unwrap();
}

Handling Exceptions with expect Function

• The expect function allows custom error messages when handling exceptions

File::open("<src>").expect("<err>");

Done

References

Bilibili - Learning for Pay Raise