Reorganizing the code

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

src/sat/sat_extension.h

@@ -0,0 +1,46 @@
+/*++
+Copyright (c) 2011 Microsoft Corporation
+
+Module Name:
+
+    sat_extension.h
+
+Abstract:
+
+    An abstract class for SAT extensions.
+
+Author:
+
+    Leonardo de Moura (leonardo) 2011-05-21.
+
+Revision History:
+
+--*/
+#ifndef _SAT_EXTENSION_H_
+#define _SAT_EXTENSION_H_
+
+#include"sat_types.h"
+#include"params.h"
+
+namespace sat {
+
+    enum check_result {
+        CR_DONE, CR_CONTINUE, CR_GIVEUP
+    };
+
+    class extension {
+    public:
+        virtual void propagate(literal l, ext_constraint_idx idx, bool & keep) = 0;
+        virtual void get_antecedents(literal l, ext_justification_idx idx, literal_vector & r) = 0;
+        virtual void asserted(literal l) = 0;
+        virtual check_result check() = 0;
+        virtual void push() = 0;
+        virtual void pop(unsigned n) = 0;
+        virtual void simplify() = 0;
+        virtual void clauses_modifed() = 0;
+        virtual lbool get_phase(bool_var v) = 0;
+    };
+
+};
+
+#endif