my_math.mirah

class MyMath

  def factoral(n:int); returns int
    if n == 0
      return 1
    elsif n > 0
      return factoral(n - 1) * n
    else n < 0
      raise("Sorry, no negative numbers please")
      return 0
    end
  end

end

mm = MyMath.new
puts ""
puts "factoral of 5 if #{mm.factoral(5)}"
puts "factoral of -5 if #{mm.factoral(-5)}"

MyMath.java

// Generated from my_math.mirah
public class MyMath extends java.lang.Object {
  public static void main(java.lang.String[] argv) {
    MyMath mm = null;
    mm = new MyMath();
    java.io.PrintStream temp$1 = java.lang.System.out;
    temp$1.println("");
    java.io.PrintStream temp$2 = java.lang.System.out;
    temp$2.println("factoral of 5 if " + mm.factoral(5));
    java.io.PrintStream temp$3 = java.lang.System.out;
    temp$3.println("factoral of -5 if " + mm.factoral(-5));
  }
  public int factoral(int n) {
    if ((n == 0)) {
      return 1;
    }
    else {
      if ((n > 0)) {
        return (this.factoral((n - 1)) * n);
      }
      else {
        (n < 0);
        throw new java.lang.RuntimeException("Sorry, no negative numbers please");
        return 0;
      }
    }
  }
}