Fix for compilation on older ocaml compiler

solver/mcproof.ml

@@ -71,13 +71,21 @@ module Make(L : Log_intf.S)(St : Mcsolver_types.S) = struct
     let resolved, new_clause = aux [] [] l in
     resolved, List.rev new_clause
 
+  (* List.sort_uniq is only since 4.02.0 *)
+  let sort_uniq compare l =
+    let rec aux = function
+      | x :: ((y :: _) as r) -> if compare x y = 0 then aux r else x :: aux r
+      | l -> l
+    in
+    aux (List.sort compare l)
+
   let to_list c =
     let v = St.(c.atoms) in
     let l = ref [] in
     for i = 0 to Vec.size v - 1 do
       l := (Vec.get v i) :: !l
     done;
-    let res = List.sort_uniq compare_atoms !l in
+    let res = sort_uniq compare_atoms !l in
     let l, _ = resolve res in
     if l <> [] then
       L.debug 3 "Input clause is a tautology";
@@ -251,7 +259,7 @@ module Make(L : Log_intf.S)(St : Mcsolver_types.S) = struct
       | Resolution (proof1, proof2, _) ->
         aux (aux acc proof1) proof2
     in
-    List.sort_uniq compare_cl (aux [] proof)
+    sort_uniq compare_cl (aux [] proof)
 
   (* Print proof graph *)
   let _i = ref 0

solver/mcproof.mli

@@ -6,6 +6,8 @@ Copyright 2014 Simon Cruanes
 
 module type S = Res_intf.S
 
-module Make : functor (L : Log_intf.S)(St : Mcsolver_types.S)
+module Make :
-  -> S with type atom = St.atom and type clause = St.clause and type lemma = St.proof
+  functor (L : Log_intf.S) ->
+  functor (St : Mcsolver_types.S) ->
+    S with type atom = St.atom and type clause = St.clause and type lemma = St.proof
 (** Functor to create a module building proofs from a sat-solver unsat trace. *)

solver/mcsolver_types.mli

@@ -13,7 +13,9 @@
 
 module type S = Mcsolver_types_intf.S
 
-module Make : functor (L : Log_intf.S)(E : Expr_intf.S)(Th : Plugin_intf.S with
+module Make :
-    type term = E.Term.t and type formula = E.Formula.t)
+  functor (L : Log_intf.S) ->
-  -> S with type term = E.Term.t and type formula = E.Formula.t and type proof = Th.proof
+  functor (E : Expr_intf.S) ->
+  functor (Th : Plugin_intf.S with type term = E.Term.t and type formula = E.Formula.t) ->
+    S with type term = E.Term.t and type formula = E.Formula.t and type proof = Th.proof
 (** Functor to instantiate the types of clauses for the Solver. *)

solver/res.ml

@@ -71,13 +71,21 @@ module Make(L : Log_intf.S)(St : Solver_types.S) = struct
     let resolved, new_clause = aux [] [] l in
     resolved, List.rev new_clause
 
+  (* List.sort_uniq is only since 4.02.0 *)
+  let sort_uniq compare l =
+    let rec aux = function
+      | x :: ((y :: _) as r) -> if compare x y = 0 then aux r else x :: aux r
+      | l -> l
+    in
+    aux (List.sort compare l)
+
   let to_list c =
     let v = St.(c.atoms) in
     let l = ref [] in
     for i = 0 to Vec.size v - 1 do
       l := (Vec.get v i) :: !l
     done;
-    let l, res = resolve (List.sort_uniq compare_atoms !l) in
+    let l, res = resolve (sort_uniq compare_atoms !l) in
     if l <> [] then
       raise (Resolution_error "Input clause is a tautology");
     res
@@ -250,7 +258,7 @@ module Make(L : Log_intf.S)(St : Solver_types.S) = struct
       | Resolution (proof1, proof2, _) ->
         aux (aux acc proof1) proof2
     in
-    List.sort_uniq compare_cl (aux [] proof)
+    sort_uniq compare_cl (aux [] proof)
 
   (* Print proof graph *)
   let _i = ref 0

solver/res.mli

@@ -6,6 +6,8 @@ Copyright 2014 Simon Cruanes
 
 module type S = Res_intf.S
 
-module Make : functor (L : Log_intf.S)(St : Solver_types.S)
+module Make :
-  -> S with type atom= St.atom and type clause = St.clause and type lemma = St.proof
+  functor (L : Log_intf.S) ->
+  functor (St : Solver_types.S) ->
+    S with type atom= St.atom and type clause = St.clause and type lemma = St.proof
 (** Functor to create a module building proofs from a sat-solver unsat trace. *)

solver/solver_types.mli

@@ -13,6 +13,8 @@
 
 module type S = Solver_types_intf.S
 
-module Make : functor (F : Formula_intf.S)(Th : Theory_intf.S)
+module Make :
-  -> S with type formula = F.t and type proof = Th.proof
+  functor (F : Formula_intf.S) ->
+  functor (Th : Theory_intf.S) ->
+    S with type formula = F.t and type proof = Th.proof
 (** Functor to instantiate the types of clauses for the Solver. *)