#define N 2000

datatype color =
  | Black 
  | Blue 
  | Green 
  | Cyan 
  | Red 
  | Magenta 
  | Brown 
  | LightGray 
  | DarkGray 
  | LightBlue 
  | LightGreen 
  | LightCyan 
  | LightRed 
  | Pink 
  | Yellow 
  | White 


typedef screenChar = @{ ascii_character = char, color_code = uint8}

vtypedef writer  = [l : agz] @{position = [a:int | a >= 0 && a < N] int (a), color_code = uint8 , buffer = (@[screenChar][N] @ l | ptr l)}

fun print_char(c : char) : void