Updated optimization ML API. Addresses #776.

src/api/ml/z3.mli

@@ -3236,33 +3236,28 @@ sig
 
   (** Asssert a soft constraint.
       Supply integer weight and string that identifies a group
-      of soft constraints.
-  *)
+      of soft constraints. *)
   val add_soft : optimize -> Expr.expr -> string -> Symbol.symbol -> handle
 
-  (** Add maximization objective.
-  *)
+  (** Add maximization objective. *)
   val maximize : optimize -> Expr.expr -> handle
 
-  (** Add minimization objective.
-  *)
+  (** Add minimization objective. *)
   val minimize : optimize -> Expr.expr -> handle
 
-  (** Checks whether the assertions in the context are satisfiable and solves objectives.
-  *)
+  (** Checks whether the assertions in the context are satisfiable and solves objectives. *)
   val check : optimize -> Solver.status
 
   (** Retrieve model from satisfiable context *)
   val get_model : optimize -> Model.model option
 
   (** Retrieve lower bound in current model for handle *)
-  val get_lower : handle -> int -> Expr.expr
+  val get_lower : handle -> Expr.expr
 
   (** Retrieve upper bound in current model for handle *)
-  val get_upper : handle -> int -> Expr.expr
+  val get_upper : handle -> Expr.expr
 
-  (** Creates a backtracking point.
-      {!pop} *)
+  (** Creates a backtracking point. {!pop} *)
   val push : optimize -> unit
 
   (** Backtrack one backtracking point.
@@ -3278,6 +3273,27 @@ sig
 
   (** Retrieve statistics information from the last call to check *)
   val get_statistics : optimize -> Statistics.statistics
+
+  (** Parse an SMT-LIB2 file with assertions, soft constraints and optimization
+      objectives. Add the parsed constraints and objectives to the optimization 
+      context. *)
+  val from_file : optimize -> string -> unit
+
+  (** Parse an SMT-LIB2 string with assertions, soft constraints and optimization 
+      objectives. Add the parsed constraints and objectives to the optimization 
+      context. *)
+  val from_string : optimize -> string -> unit
+                                            
+  (** Return the set of asserted formulas on the optimization context. *) 
+  val get_assertions : optimize -> Expr.expr list
+
+  (** Return objectives on the optimization context. If the objective function 
+      is a max-sat objective it is returned as a Pseudo-Boolean (minimization) 
+      sum of the form (+ (if f1 w1 0) (if f2 w2 0) ...). If the objective 
+      function is entered as a maximization objective, then return the 
+      corresponding minimization objective. In this way the resulting 
+      objective function is always returned as a minimization objective. *)
+  val get_objectives : optimize -> Expr.expr list
 end