Reorganizing the code. Moved nlsat to its own directory.

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

src/ast/for_each_expr.cpp

@@ -0,0 +1,65 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    for_each_expr.cpp
+
+Abstract:
+
+    <abstract>
+
+Author:
+
+    Leonardo de Moura (leonardo) 2007-12-28.
+
+Revision History:
+
+--*/
+
+#include"for_each_expr.h"
+
+struct expr_counter_proc {
+    unsigned m_num;
+    expr_counter_proc():m_num(0) {}
+    void operator()(var * n)        { m_num++; }
+    void operator()(app * n)        { m_num++; if (n->get_decl()->is_associative()) m_num += n->get_num_args() - 2; }
+    void operator()(quantifier * n) { m_num++; }
+};
+
+unsigned get_num_exprs(expr * n, expr_mark & visited) {
+    expr_counter_proc counter;
+    for_each_expr(counter, visited, n);
+    return counter.m_num;
+}
+
+unsigned get_num_exprs(expr * n, expr_fast_mark1 & visited) {
+    expr_counter_proc counter;
+    for_each_expr_core<expr_counter_proc, expr_fast_mark1, false, false>(counter, visited, n);
+    return counter.m_num;
+}
+
+unsigned get_num_exprs(expr * n) {
+    expr_fast_mark1 visited;
+    return get_num_exprs(n, visited);
+}
+
+namespace has_skolem_functions_ns {
+    struct found {}; 
+    struct proc {
+        void operator()(var * n) const {}
+        void operator()(app const * n) const { if (n->get_decl()->is_skolem() && n->get_num_args() > 0) throw found(); }
+        void operator()(quantifier * n) const {}
+    };
+};
+
+bool has_skolem_functions(expr * n) {
+    has_skolem_functions_ns::proc p;
+    try {
+        for_each_expr(p, n);
+    }
+    catch (has_skolem_functions_ns::found) {
+        return true;
+    }
+    return false;
+}