Error Handling with Result Type

Snippet

Error Handling with Result Type

Rust uses the Result type for error handling without exceptions. Result is an enum with two variants: Ok(T) for success containing a value, and Err(E) for failure containing an error message. This approach makes errors explicit and forces you to handle them. The compiler will warn you if you ignore a Result that could fail.

snippet.rs
rust
fn divide(a: f64, b: f64) -> Result<f64, String> {
    if b == 0.0 {
        return Err(String::from("Division by zero"));
    }
    Ok(a / b)
}
 
fn main() {
    match divide(10.0, 0.0) {
        Ok(result) => println!("Result: {}", result),
        Err(e) => println!("Error: {}", e),
    }
}

Breakdown

Result<f64, String>

Return type that can be either Ok with f64 or Err with String

return Err(String::from("Division by zero"));

Returns an error variant when dividing by zero

Ok(a / b)

Returns the successful result wrapped in Ok variant

match divide(10.0, 0.0)

Pattern matches to handle both success and failure cases

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