Reorganizing code. Added script for generating VS project files

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

src/ast/recurse_expr.h

@@ -0,0 +1,47 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    recurse_expr.h
+
+Abstract:
+
+    Traverse an expression applying a visitor.
+
+Author:
+
+    Leonardo de Moura (leonardo) 2008-01-11.
+
+Revision History:
+
+--*/
+#ifndef _RECURSE_EXPR_H_
+#define _RECURSE_EXPR_H_
+
+#include"ast.h"
+#include"obj_hashtable.h"
+
+template<typename T, typename Visitor, bool IgnorePatterns=false, bool CallDestructors=true>
+class recurse_expr : public Visitor {
+    obj_map<expr, T>                          m_cache;
+    ptr_vector<expr>                          m_todo;
+    vector<T, CallDestructors>                m_results1;
+    vector<T, CallDestructors>                m_results2;
+
+    bool is_cached(expr * n) const { T c; return m_cache.find(n, c); }
+    T get_cached(expr * n) const { T c; m_cache.find(n, c); return c; }
+    void cache_result(expr * n, T c) { m_cache.insert(n, c); }
+    
+    void visit(expr * n, bool & visited);
+    bool visit_children(expr * n);
+    void process(expr * n);
+    
+public:
+    recurse_expr(Visitor const & v = Visitor()):Visitor(v) {}
+    T operator()(expr * n);
+    void reset() { m_cache.reset(); m_todo.reset(); }
+    void finalize() { m_cache.finalize(); m_todo.finalize(); }
+};
+
+#endif /* _RECURSE_EXPR_H_ */