feat: decoders for LRA terms

src/base/LRA_term.ml

@@ -141,23 +141,43 @@ let ops =
   in
   { Const.Ops.equal; hash; ser; pp }
 
-(* TODO
-   let deser _tst =
-     Ser_decode.
+let const_decoders : Const.decoders =
   [
     ( "Qn",
+      ops,
+      Ser_decode.(
+        fun _ ->
           let* s = string in
           let+ q =
             unwrap_opt "expected rational number"
               (Sidekick_zarith.Rational.of_string s)
           in
-           Const q );
+          Const q) );
     ( "Qp",
+      ops,
+      Ser_decode.(
+        fun _ ->
           let* s = string in
           let+ p = unwrap_opt "expected predicate" (Pred.of_string s) in
-           Pred p );
+          Pred p) );
+    ( "Qo",
+      ops,
+      Ser_decode.(
+        fun _ ->
+          let* s = string in
+          let+ o = unwrap_opt "expected LRA operator" (Op.of_string s) in
+          Op o) );
+    ( "Q*",
+      ops,
+      Ser_decode.(
+        fun _ ->
+          let* s = string in
+          let+ q =
+            unwrap_opt "expected rational number"
+              (Sidekick_zarith.Rational.of_string s)
+          in
+          Mult_by q) );
   ]
-*)
 
 let real tst = Ty.real tst
 let has_ty_real t = Ty.is_real (T.ty t)

src/base/LRA_term.mli

@@ -12,6 +12,8 @@ module Op : sig
   include Sidekick_sigs.EQ_HASH_PRINT with type t := t
 end
 
+val const_decoders : Const.decoders
+
 module View : sig
   type ('num, 'a) lra_view = ('num, 'a) Sidekick_th_lra.lra_view =
     | LRA_pred of Pred.t * 'a * 'a