streamline pb solver interface and naming after removal of xor

src/sat/smt/pb_card.h

@@ -0,0 +1,55 @@
+/*++
+Copyright (c) 2017 Microsoft Corporation
+
+Module Name:
+
+    ba_card.h
+
+Abstract:
+ 
+    Interface for Cardinality constraints.
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2017-01-30
+
+--*/
+
+#pragma once 
+
+#include "sat/sat_types.h"
+#include "sat/smt/pb_constraint.h"
+
+
+namespace pb {
+
+    class card : public constraint {
+        literal        m_lits[0];
+    public:
+        static size_t get_obj_size(unsigned num_lits) { return sat::constraint_base::obj_size(sizeof(card) + num_lits * sizeof(literal)); }
+        card(unsigned id, literal lit, literal_vector const& lits, unsigned k);
+        literal operator[](unsigned i) const { return m_lits[i]; }
+        literal& operator[](unsigned i) { return m_lits[i]; }
+        literal const* begin() const { return m_lits; }
+        literal const* end() const { return static_cast<literal const*>(m_lits) + m_size; }
+        void negate() override;
+        void swap(unsigned i, unsigned j) override { std::swap(m_lits[i], m_lits[j]); }
+        literal_vector literals() const override { return literal_vector(m_size, m_lits); }
+        bool is_watching(literal l) const override;
+        literal get_lit(unsigned i) const override { return m_lits[i]; }
+        void set_lit(unsigned i, literal l) override { m_lits[i] = l; }
+        unsigned get_coeff(unsigned i) const override { return 1; }
+        double get_reward(solver_interface const& s, sat::literal_occs_fun& occs) const override;
+        std::ostream& display(std::ostream& out) const override;
+        std::ostream& display(std::ostream& out, solver_interface const& s, bool values) const override;
+        void clear_watch(solver_interface& s) override;
+        bool init_watch(solver_interface& s) override;        
+        bool is_extended_binary(literal_vector& r) const override;
+        bool validate_unit_propagation(solver_interface const& s, literal alit) const override;
+        lbool eval(sat::model const& m) const override;
+        lbool eval(solver_interface const& s) const override;
+        void init_use_list(sat::ext_use_list& ul) const override;
+        bool is_blocked(sat::simplifier& s, literal lit) const override;
+
+    };
+}