fixed gappa printer for negative literals (no space after -)

src/printer/gappa.ml

@@ -146,13 +146,13 @@ let print_ident fmt id =
 let number_format = {
     Number.long_int_support = true;
     Number.extra_leading_zeros_support = true;
-    Number.negative_int_support = Number.Number_default;
+    Number.negative_int_support = Number.Number_custom "-%a";
     Number.dec_int_support = Number.Number_default;
     Number.hex_int_support = Number.Number_default;
     Number.oct_int_support = Number.Number_unsupported;
     Number.bin_int_support = Number.Number_unsupported;
     Number.def_int_support = Number.Number_unsupported;
-    Number.negative_real_support = Number.Number_default;
+    Number.negative_real_support = Number.Number_custom "-%a";
     Number.dec_real_support = Number.Number_default;
     Number.hex_real_support = Number.Number_default;
     Number.frac_real_support = Number.Number_unsupported;

src/util/number.ml

@@ -306,7 +306,7 @@ let print_int_constant support fmt i =
 
 let print_real_constant support fmt r =
   if r.rc_negative then
-    check_support support.negative_real_support (Some "-%a")
+    check_support support.negative_real_support (Some "(- %a)")
                   (fun def n -> fprintf fmt def (print_real_literal support) n)
                   (fun _ -> assert false)
                   r.rc_abs