fun albumTitle num =
    case num of
        1 => "The Piper at the Gates of Dawn"
     |  2 => "A Saucerful of Secrets"
     |  3 => "More"
     |  4 => "Ummagumma"
     |  5 => "Atom Heart Mother"
     |  6 => "Meddle"
     |  7 => "Obscured By Clouds"
     |  8 => "The Dark Side of the Moon"
     |  9 => "Wish You Were Here"
     | 10 => "Animals"
     | 11 => "The Wall"
     | 12 => "The Final Cut"
     | 13 => "A Momentary Lapse of Reason"
     | 14 => "Division Bell"

fun lastAppearance "Syd Barrett"  =  2
 |  lastAppearance "Roger Waters" = 12
 |  lastAppearance x = ~1

fun sum a b =
   case a + b of
      0 => "zero"
    | 1 => "one"
    | 2 => "two"
    | n => if n < 10 then
               "a lot"
           else
               "really a lot"