Result

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Additional Resources

• A Simpler Way to See Results

Exercises

Mathing result

// Complete the match statement to check whether operation succeeded or not.

enum Operation {
    Add(i32, i32),
    Mul(i32, i32),
    Sub { first: i32, second: i32 },
    Div { divident: i32, divisor: i32 },
}

impl Operation {
    fn execute(self) -> Result<i32, String> {
        match self {
            Self::Add(a, b) => Ok(a + b),
            Self::Mul(a, b) => Ok(a * b),
            Self::Sub { first, second } => Ok(first - second),
            Self::Div { divident, divisor } => {
                if divisor == 0 {
                    Err(String::from("Can not divide by zero"))
                } else {
                    Ok(divident / divisor)
                }
            }
        }
    }
}

fn main() {
    let user_input = Operation::Div {
        divident: 20,
        divisor: 0,
    };
    match user_input.execute() {
         => println!("Result: {res}"),
         => println!("Error: {e}"),
    }
}

enum Operation {
  Add(i32, i32),
  Mul(i32, i32),
  Sub { first: i32, second: i32 },
  Div { divident: i32, divisor: i32 },
}

impl Operation {
  fn execute(self) -> Result<i32, String> {
      match self {
          Self::Add(a, b) => Ok(a + b),
          Self::Mul(a, b) => Ok(a * b),
          Self::Sub { first, second } => Ok(first - second),
          Self::Div { divident, divisor } => {
              if divisor == 0 {
                  Err(String::from("Can not divide by zero"))
              } else {
                  Ok(divident / divisor)
              }
          }
      }
  }
}

fn main() {
  let user_input = Operation::Div {
      divident: 20,
      divisor: 0,
  };
  match user_input.execute() {
      Ok(res) => println!("Result: {res}"),
      Err(e) => println!("Error: {e}"),
  }
}

Returning result

// Complete the function signature.

fn greet(name: &str) -> {
    if name.len() > 0 {
        println!("Hello {name}!");
        Ok(())
    } else {
        Err("Empty name provided".to_string())
    }
}

fn main() {
    let name = "Tom";
    if let Err(e) = greet(name) {
        println!("Error: {e}");
    }
}

fn greet(name: &str) -> Result<(), String> {
  if name.len() > 0 {
      println!("Hello {name}!");
      Ok(())
  } else {
      Err("Empty name provided".to_string())
  }
}

fn main() {
  let name = "Tom";
  if let Err(e) = greet(name) {
      println!("Error: {e}");
  }
}