let pp_print_constant ppf = function
PconstInteger x -> pp_print_string ppf x
| PconstFloat x -> pp_print_string ppf x
| PconstChar x -> pp_print_string ppf x
| PconstString [] -> pp_print_string ppf "\"\""
| PconstString l -> List.iter
(fun x -> print_string ("\"" ^ x ^ "\" ")) l