Factorial recursive algorithm in Rust language

factorial.rs

fn factorial(value: int) -> int {
 if value==0 { ret 1; }
 else { ret value * factorial(value-1); } 
 
}

fn main(args: [str]) {
  let init_value = option::get(int::from_str(args[1]));
  let final_value = int::str(factorial(init_value));
  io::println(final_value);
}

Just in-case (noone wanted this) anyone wanted it updated to 2020

fn factorial(x: i32) -> i32 {
    if x == 0 {
        1
    } else {
        x * factorial(x-1)
    }
}

Yes, this is a code from, maybe, alpha or pre-alpha rust. I was just trying to learn it.

The language changed over the time until the initial version was released, so this code doesn't run anymore.