rustHow to use boxed errors in Rust

Boxed errors in Rust are a way to handle errors in a more structured way. It allows you to store errors in a box, which can then be used to propagate the error up the call stack. This makes it easier to handle errors in a more organized way.

Here is an example of how to use boxed errors in Rust:

use std::error::Error;

fn main() -> Result<(), Box<dyn Error>> {
    let result = do_something()?;
    println!("Result: {}", result);
    Ok(())
}

fn do_something() -> Result<i32, Box<dyn Error>> {
    let result = 10;
    Ok(result)
}

Output

Result: 10

Explanation of code parts:

1. use std::error::Error;: This imports the Error trait from the standard library, which is needed for using boxed errors.

2. fn main() -> Result<(), Box<dyn Error>> {: This is the main function, which returns a Result type with an empty tuple as the success type and a Box of a dynamic Error type as the error type.

3. let result = do_something()?;: This line calls the do_something() function and uses the ? operator to propagate any errors that occur up the call stack.

4. fn do_something() -> Result<i32, Box<dyn Error>> {: This is the do_something() function, which returns a Result type with an i32 as the success type and a Box of a dynamic Error type as the error type.

5. let result = 10;: This line assigns the value 10 to the result variable.

6. Ok(result): This line returns the result variable as a success value in the Result type.

Helpful links:

1. https://doc.rust-lang.org/std/error/trait.Error.html
2. https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html

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