message: Update DL-* pretty printer.
diff: @@ -69,6 +69,34 @@ write_expr(eindex(E1, E2)) :-
  write('['),
  write_expr(E2),
  write(']').
  +write_expr(eleft(E)) :-
  + write('inl '),
  + write_expr(E).
  +write_expr(eright(E)) :-
  + write('inr '),
  + write_expr(E).
  +write_expr(ecase(E, X, E1, E2)) :-
  + write('case '),
  + write_expr(E),
  + format(' ~w ', [X]),
  + write_expr(E1),
  + write(' '),
  + write_expr(E2).
  +write_expr(eplus(E1, E2)) :-
  + write('('),
  + write_expr(E1),
  + write(' + '),
  + write_expr(E2),
  + write(')').
  +write_expr(etimes(E1, E2)) :-
  + write('('),
  + write_expr(E1),
  + write(' * '),
  + write_expr(E2),
  + write(')').
  +write_expr(eminus(E)) :-
  + write('-'),
  + write_expr(E).
  write_struct(enil) :-
  write(' }').
  