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/********************* */
/*! \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 */
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