1 files changed, 83 insertions, 0 deletions
diff --git a/src/theory/quantifiers/term_enumeration.h b/src/theory/quantifiers/term_enumeration.h
new file mode 100644
index 000000000..a96718800
--- /dev/null
+++ b/src/theory/quantifiers/term_enumeration.h
@@ -0,0 +1,83 @@
+/*********************                                                        */
+/*! \file term_enumeration.h
+ ** \verbatim
+ ** Top contributors (to current version):
+ **   Andrew Reynolds
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2017 by the authors listed in the file AUTHORS
+ ** in the top-level source directory) and their institutional affiliations.
+ ** All rights reserved.  See the file COPYING in the top-level source
+ ** directory for licensing information.\endverbatim
+ **
+ ** \brief utilities for term enumeration
+ **/
+
+#include "cvc4_private.h"
+
+#ifndef __CVC4__THEORY__QUANTIFIERS__TERM_ENUMERATION_H
+#define __CVC4__THEORY__QUANTIFIERS__TERM_ENUMERATION_H
+
+#include <unordered_map>
+#include <vector>
+
+#include "expr/node.h"
+#include "expr/type_node.h"
+#include "theory/type_enumerator.h"
+
+namespace CVC4 {
+namespace theory {
+namespace quantifiers {
+
+/** Term enumeration
+ *
+ * This class has utilities for enumerating terms. It stores
+ * a cache of terms enumerated per each type.
+ * It also has various utility functions regarding type
+ * enumeration.
+ */
+class TermEnumeration
+{
+ public:
+  TermEnumeration() {}
+  ~TermEnumeration() {}
+  /** get i^th term for type tn */
+  Node getEnumerateTerm(TypeNode tn, unsigned i);
+  /** is closed enumerable type
+   *
+   * This returns true if this type has an enumerator that produces
+   * constants that are handled by ground theory solvers.
+   * Examples of types that are not closed enumerable are:
+   * (1) uninterpreted sorts,
+   * (2) arrays,
+   * (3) codatatypes,
+   * (4) parametric sorts involving any of the above.
+   */
+  bool isClosedEnumerableType(TypeNode tn);
+  /** may complete type
+   *
+   * Returns true if the type tn is closed 
+   * enumerable, and is small enough
+   * for finite model finding to enumerate it,
+   * by some heuristic (current cardinality < 1000).
+   */
+  bool mayComplete(TypeNode tn);
+
+ private:
+  /** ground terms enumerated for types */
+  std::unordered_map<TypeNode, std::vector<Node>, TypeNodeHashFunction>
+      d_enum_terms;
+  /** map from type to the index of its type enumerator in d_typ_enum. */
+  std::unordered_map<TypeNode, size_t, TypeNodeHashFunction> d_typ_enum_map;
+  /** type enumerators */
+  std::vector<TypeEnumerator> d_typ_enum;
+  /** closed enumerable type cache */
+  std::unordered_map<TypeNode, bool, TypeNodeHashFunction> d_typ_closed_enum;
+  /** may complete */
+  std::unordered_map<TypeNode, bool, TypeNodeHashFunction> d_may_complete;
+};
+
+} /* CVC4::theory::quantifiers namespace */
+} /* CVC4::theory namespace */
+} /* CVC4 namespace */
+
+#endif /* __CVC4__THEORY__QUANTIFIERS__TERM_ENUMERATION_H */