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GCC Code Coverage Report

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File:	src/theory/ext_theory.h	Lines:	7	7	100.0 %
Date:	2021-08-01	Branches:	1	2	50.0 %


/******************************************************************************
 * Top contributors (to current version):
 *   Andrew Reynolds, Tim King, Mathias Preiner
 *
 * This file is part of the cvc5 project.
 *
 * Copyright (c) 2009-2021 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.
 * ****************************************************************************
 *
 * Extended theory interface.
 *
 * This implements a generic module, used by theory solvers, for performing
 * "context-dependent simplification", as described in Reynolds et al
 * "Designing Theory Solvers with Extensions", FroCoS 2017.
 *
 * At a high level, this technique implements a generic inference scheme based
 * on the combination of SAT-context-dependent equality reasoning and
 * SAT-context-indepedent rewriting.
 *
 * As a simple example, say
 * (1) TheoryStrings tells us that the following facts hold in the SAT context:
 *     x = "A" ^ str.contains( str.++( x, z ), "B" ) = true.
 * (2) The Rewriter tells us that:
 *     str.contains( str.++( "A", z ), "B" ) ----> str.contains( z, "B" ).
 * From this, this class may infer that the following lemma is T-valid:
 *   x = "A" ^ str.contains( str.++( x, z ), "B" ) => str.contains( z, "B" )
 */

#include "cvc5_private.h"

#ifndef CVC5__THEORY__EXT_THEORY_H
#define CVC5__THEORY__EXT_THEORY_H

#include <map>

#include "context/cdhashmap.h"
#include "context/cdhashset.h"
#include "context/cdo.h"
#include "context/context.h"
#include "expr/node.h"

namespace cvc5 {
namespace theory {

class OutputChannel;

/** Reasons for why a term was marked reduced */
enum class ExtReducedId
{
  UNKNOWN,
  // the extended function substitutes+rewrites to a constant
  SR_CONST,
  // the extended function was reduced by the callback
  REDUCTION,
  // the extended function substitutes+rewrites to zero
  ARITH_SR_ZERO,
  // the extended function substitutes+rewrites to a linear (non-zero) term
  ARITH_SR_LINEAR,
  // an extended string function substitutes+rewrites to a constant
  STRINGS_SR_CONST,
  // a negative str.contains was reduced to a disequality
  STRINGS_NEG_CTN_DEQ,
  // a positive str.contains was reduced to an equality
  STRINGS_POS_CTN,
  // a str.contains was subsumed by another based on a decomposition
  STRINGS_CTN_DECOMPOSE,
  // reduced via an intersection inference
  STRINGS_REGEXP_INTER,
  // subsumed due to intersection reasoning
  STRINGS_REGEXP_INTER_SUBSUME,
  // subsumed due to RE inclusion reasoning for positive memberships
  STRINGS_REGEXP_INCLUDE,
  // subsumed due to RE inclusion reasoning for negative memberships
  STRINGS_REGEXP_INCLUDE_NEG,
};
/**
 * Converts an ext reduced identifier to a string.
 *
 * @param id The ext reduced identifier
 * @return The name of the ext reduced identifier
 */
const char* toString(ExtReducedId id);

/**
 * Writes an ext reduced identifier to a stream.
 *
 * @param out The stream to write to
 * @param id The ext reduced identifier to write to the stream
 * @return The stream
 */
std::ostream& operator<<(std::ostream& out, ExtReducedId id);

/**
 * A callback class for ExtTheory below. This class is responsible for
 * determining how to apply context-dependent simplification.
 */
class ExtTheoryCallback
{
 public:
  virtual ~ExtTheoryCallback() {}
  /*
   * Get current substitution at an effort
   * @param effort The effort identifier
   * @param vars The variables to get a substitution for
   * @param subs The terms to substitute for variables, in order. This vector
   * should be updated to one the same size as vars.
   * @param exp The map containing the explanation for each variable. Together
   * with subs, we have that:
   *   ( exp[vars[i]] => vars[i] = subs[i] ) holds for all i
   * @return true if any (non-identity) substitution was added to subs.
   */
  virtual bool getCurrentSubstitution(int effort,
                                      const std::vector<Node>& vars,
                                      std::vector<Node>& subs,
                                      std::map<Node, std::vector<Node> >& exp);

  /*
   * Is extended function n reduced? This returns true if n is reduced to a
   * form that requires no further interaction from the theory.
   *
   * @param effort The effort identifier
   * @param n The term to reduce
   * @param on The original form of n, before substitution
   * @param exp The explanation of on = n
   * @param id If this method returns true, then id is updated to the reason
   * why n was reduced.
   * @return true if n is reduced.
   */
  virtual bool isExtfReduced(
      int effort, Node n, Node on, std::vector<Node>& exp, ExtReducedId& id);

  /**
   * Get reduction for node n.
   * If return value is true, then n is reduced.
   * If satDep is updated to false, then n is reduced independent of the
   * SAT context (e.g. by a lemma that persists at this
   * user-context level).
   * If nr is non-null, then ( n = nr ) should be added as a lemma by caller,
   * and return value of this method should be true.
   */
  virtual bool getReduction(int effort, Node n, Node& nr, bool& satDep);
};

/** Extended theory class
 *
 * This class is used for constructing generic extensions to theory solvers.
 * In particular, it provides methods for "context-dependent simplification"
 * and "model-based refinement". For details, see Reynolds et al "Design
 * Theory Solvers with Extensions", FroCoS 2017.
 *
 * It maintains:
 * (1) A set of "extended function" kinds (d_extf_kind),
 * (2) A database of active/inactive extended function terms (d_ext_func_terms)
 * that have been registered to the class.
 *
 * This class has methods doInferences/doReductions, which send out lemmas
 * based on the current set of active extended function terms. The former
 * is based on context-dependent simplification, where this class asks the
 * underlying theory for a "derivable substitution", whereby extended functions
 * may be reducable.
 */
class ExtTheory
{
  using NodeBoolMap = context::CDHashMap<Node, bool>;
  using NodeExtReducedIdMap = context::CDHashMap<Node, ExtReducedId>;
  using NodeSet = context::CDHashSet<Node>;

 public:
  /** constructor
   *
   * If cacheEnabled is false, we do not cache results of getSubstitutedTerm.
   */
  ExtTheory(ExtTheoryCallback& p,
            context::Context* c,
            context::UserContext* u,
            OutputChannel& out);
  virtual ~ExtTheory() {}
  /** Tells this class to treat terms with Kind k as extended functions */
  void addFunctionKind(Kind k) { d_extf_kind[k] = true; }
  /** Is kind k treated as an extended function by this class? */
  bool hasFunctionKind(Kind k) const
  {
    return d_extf_kind.find(k) != d_extf_kind.end();
  }
  /** register term
   *
   * Registers term n with this class. Adds n to the set of extended function
   * terms known by this class (d_ext_func_terms) if n is an extended function,
   * that is, if addFunctionKind( n.getKind() ) was called.
   */
  void registerTerm(Node n);
  /** set n as reduced/inactive
   *
   * If satDep = false, then n remains inactive in the duration of this
   * user-context level
   */
  void markReduced(Node n, ExtReducedId rid, bool satDep = true);
  /** getSubstitutedTerms
   *
   *  input : effort, terms
   *  output : sterms, exp, where ( exp[i] => terms[i] = sterms[i] ) for all i.
   *
   * For each i, sterms[i] = term[i] * sigma for some "derivable substitution"
   * sigma. We obtain derivable substitutions and their explanations via calls
   * to the underlying theory's Theory::getCurrentSubstitution method.
   */
  void getSubstitutedTerms(int effort,
                           const std::vector<Node>& terms,
                           std::vector<Node>& sterms,
                           std::vector<std::vector<Node> >& exp);
  /**
   * Same as above, but for a single term. We return the substituted form of
   * term and add its explanation to exp.
   */
  Node getSubstitutedTerm(int effort, Node term, std::vector<Node>& exp);
  /** doInferences
   *
   * This function performs "context-dependent simplification". The method takes
   * as input:
   *  effort: an identifier used to determine which terms we reduce and the
   *          form of the derivable substitution we will use,
   *  terms: the set of terms to simplify,
   *  batch: if this flag is true, we send lemmas for all terms; if it is false
   *         we send a lemma for the first applicable term.
   *
   * Sends rewriting lemmas of the form ( exp => t = c ) where t is in terms
   * and c is a constant, c = rewrite( t*sigma ) where exp |= sigma. These
   * lemmas are determined by asking the underlying theory for a derivable
   * substitution (through getCurrentSubstitution with getSubstitutedTerm)
   * above, applying this substitution to terms in terms, rewriting
   * the result and checking with the theory whether the resulting term is
   * in reduced form (isExtfReduced).
   *
   * This method adds the extended terms that are still active to nred, and
   * returns true if and only if a lemma of the above form was sent.
   */
  bool doInferences(int effort,
                    const std::vector<Node>& terms,
                    std::vector<Node>& nred,
                    bool batch = true);
  /**
   * Calls the above function, where terms is getActive(), the set of currently
   * active terms.
   */
  bool doInferences(int effort, std::vector<Node>& nred, bool batch = true);
  /** doReductions
   *
   * This method has the same interface as doInferences. In contrast to
   * doInfereces, this method will send reduction lemmas of the form ( t = t' )
   * where t is in terms and t' is an equivalent reduced term.
   */
  bool doReductions(int effort,
                    const std::vector<Node>& terms,
                    std::vector<Node>& nred,
                    bool batch = true);
  bool doReductions(int effort, std::vector<Node>& nred, bool batch = true);

  /** get the set of all extended function terms from d_ext_func_terms */
  void getTerms(std::vector<Node>& terms);
  /** is there at least one active extended function term? */
  bool hasActiveTerm() const;
  /** is n an active extended function term? */
  bool isActive(Node n) const;
  /**
   * Same as above, but rid is updated to the reason if this method returns
   * false.
   */
  bool isActive(Node n, ExtReducedId& rid) const;
  /** get the set of active terms from d_ext_func_terms */
  std::vector<Node> getActive() const;
  /** get the set of active terms from d_ext_func_terms of kind k */
  std::vector<Node> getActive(Kind k) const;

 private:
  /** returns the set of variable subterms of n */
  static std::vector<Node> collectVars(Node n);
  /** is n context dependent inactive? */
  bool isContextIndependentInactive(Node n) const;
  /**
   * Same as above, but rid is updated to the reason if this method returns
   * true.
   */
  bool isContextIndependentInactive(Node n, ExtReducedId& rid) const;
  /** do inferences internal */
  bool doInferencesInternal(int effort,
                            const std::vector<Node>& terms,
                            std::vector<Node>& nred,
                            bool batch,
                            bool isRed);
  /** send lemma on the output channel */
  bool sendLemma(Node lem, bool preprocess = false);
  /** reference to the callback */
  ExtTheoryCallback& d_parent;
  /** Reference to the output channel we are using */
  OutputChannel& d_out;
  /** the true node */
  Node d_true;
  /** extended function terms, map to whether they are active */
  NodeBoolMap d_ext_func_terms;
  /** mapping to why extended function terms are inactive */
  NodeExtReducedIdMap d_extfExtReducedIdMap;
  /**
   * The set of terms from d_ext_func_terms that are SAT-context-independent
   * inactive. For instance, a term t is SAT-context-independent inactive if
   * a reduction lemma of the form t = t' was added in this user-context level.
   */
  NodeExtReducedIdMap d_ci_inactive;
  /**
   * Watched term for checking if any non-reduced extended functions exist.
   * This is an arbitrary active member of d_ext_func_terms.
   */
  context::CDO<Node> d_has_extf;
  /** the set of kinds we are treated as extended functions */
  std::map<Kind, bool> d_extf_kind;
  /** information for each term in d_ext_func_terms */
  class ExtfInfo
  {
   public:
    /** all variables in this term */
    std::vector<Node> d_vars;
  };
  std::map<Node, ExtfInfo> d_extf_info;

  // cache of all lemmas sent
  NodeSet d_lemmas;
  NodeSet d_pp_lemmas;
};

}  // namespace theory
}  // namespace cvc5

#endif /* CVC5__THEORY__EXT_THEORY_H */


Generated by: GCOVR (Version 3.2)

Line	Exec	Source
1		/******************************************************************************
2		* Top contributors (to current version):
3		* Andrew Reynolds, Tim King, Mathias Preiner
4		*
5		* This file is part of the cvc5 project.
6		*
7		* Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
8		* in the top-level source directory and their institutional affiliations.
9		* All rights reserved. See the file COPYING in the top-level source
10		* directory for licensing information.
11		* ****************************************************************************
12		*
13		* Extended theory interface.
14		*
15		* This implements a generic module, used by theory solvers, for performing
16		* "context-dependent simplification", as described in Reynolds et al
17		* "Designing Theory Solvers with Extensions", FroCoS 2017.
18		*
19		* At a high level, this technique implements a generic inference scheme based
20		* on the combination of SAT-context-dependent equality reasoning and
21		* SAT-context-indepedent rewriting.
22		*
23		* As a simple example, say
24		* (1) TheoryStrings tells us that the following facts hold in the SAT context:
25		* x = "A" ^ str.contains( str.++( x, z ), "B" ) = true.
26		* (2) The Rewriter tells us that:
27		* str.contains( str.++( "A", z ), "B" ) ----> str.contains( z, "B" ).
28		* From this, this class may infer that the following lemma is T-valid:
29		* x = "A" ^ str.contains( str.++( x, z ), "B" ) => str.contains( z, "B" )
30		*/
31
32		#include "cvc5_private.h"
33
34		#ifndef CVC5__THEORY__EXT_THEORY_H
35		#define CVC5__THEORY__EXT_THEORY_H
36
37		#include <map>
38
39		#include "context/cdhashmap.h"
40		#include "context/cdhashset.h"
41		#include "context/cdo.h"
42		#include "context/context.h"
43		#include "expr/node.h"
44
45		namespace cvc5 {
46		namespace theory {
47
48		class OutputChannel;
49
50		/** Reasons for why a term was marked reduced */
51		enum class ExtReducedId
52		{
53		UNKNOWN,
54		// the extended function substitutes+rewrites to a constant
55		SR_CONST,
56		// the extended function was reduced by the callback
57		REDUCTION,
58		// the extended function substitutes+rewrites to zero
59		ARITH_SR_ZERO,
60		// the extended function substitutes+rewrites to a linear (non-zero) term
61		ARITH_SR_LINEAR,
62		// an extended string function substitutes+rewrites to a constant
63		STRINGS_SR_CONST,
64		// a negative str.contains was reduced to a disequality
65		STRINGS_NEG_CTN_DEQ,
66		// a positive str.contains was reduced to an equality
67		STRINGS_POS_CTN,
68		// a str.contains was subsumed by another based on a decomposition
69		STRINGS_CTN_DECOMPOSE,
70		// reduced via an intersection inference
71		STRINGS_REGEXP_INTER,
72		// subsumed due to intersection reasoning
73		STRINGS_REGEXP_INTER_SUBSUME,
74		// subsumed due to RE inclusion reasoning for positive memberships
75		STRINGS_REGEXP_INCLUDE,
76		// subsumed due to RE inclusion reasoning for negative memberships
77		STRINGS_REGEXP_INCLUDE_NEG,
78		};
79		/**
80		* Converts an ext reduced identifier to a string.
81		*
82		* @param id The ext reduced identifier
83		* @return The name of the ext reduced identifier
84		*/
85		const char* toString(ExtReducedId id);
86
87		/**
88		* Writes an ext reduced identifier to a stream.
89		*
90		* @param out The stream to write to
91		* @param id The ext reduced identifier to write to the stream
92		* @return The stream
93		*/
94		std::ostream& operator<<(std::ostream& out, ExtReducedId id);
95
96		/**
97		* A callback class for ExtTheory below. This class is responsible for
98		* determining how to apply context-dependent simplification.
99		*/
100	14972	class ExtTheoryCallback
101		{
102		public:
103	14972	virtual ~ExtTheoryCallback() {}
104		/*
105		* Get current substitution at an effort
106		* @param effort The effort identifier
107		* @param vars The variables to get a substitution for
108		* @param subs The terms to substitute for variables, in order. This vector
109		* should be updated to one the same size as vars.
110		* @param exp The map containing the explanation for each variable. Together
111		* with subs, we have that:
112		* ( exp[vars[i]] => vars[i] = subs[i] ) holds for all i
113		* @return true if any (non-identity) substitution was added to subs.
114		*/
115		virtual bool getCurrentSubstitution(int effort,
116		const std::vector<Node>& vars,
117		std::vector<Node>& subs,
118		std::map<Node, std::vector<Node> >& exp);
119
120		/*
121		* Is extended function n reduced? This returns true if n is reduced to a
122		* form that requires no further interaction from the theory.
123		*
124		* @param effort The effort identifier
125		* @param n The term to reduce
126		* @param on The original form of n, before substitution
127		* @param exp The explanation of on = n
128		* @param id If this method returns true, then id is updated to the reason
129		* why n was reduced.
130		* @return true if n is reduced.
131		*/
132		virtual bool isExtfReduced(
133		int effort, Node n, Node on, std::vector<Node>& exp, ExtReducedId& id);
134
135		/**
136		* Get reduction for node n.
137		* If return value is true, then n is reduced.
138		* If satDep is updated to false, then n is reduced independent of the
139		* SAT context (e.g. by a lemma that persists at this
140		* user-context level).
141		* If nr is non-null, then ( n = nr ) should be added as a lemma by caller,
142		* and return value of this method should be true.
143		*/
144		virtual bool getReduction(int effort, Node n, Node& nr, bool& satDep);
145		};
146
147		/** Extended theory class
148		*
149		* This class is used for constructing generic extensions to theory solvers.
150		* In particular, it provides methods for "context-dependent simplification"
151		* and "model-based refinement". For details, see Reynolds et al "Design
152		* Theory Solvers with Extensions", FroCoS 2017.
153		*
154		* It maintains:
155		* (1) A set of "extended function" kinds (d_extf_kind),
156		* (2) A database of active/inactive extended function terms (d_ext_func_terms)
157		* that have been registered to the class.
158		*
159		* This class has methods doInferences/doReductions, which send out lemmas
160		* based on the current set of active extended function terms. The former
161		* is based on context-dependent simplification, where this class asks the
162		* underlying theory for a "derivable substitution", whereby extended functions
163		* may be reducable.
164		*/
165		class ExtTheory
166		{
167		using NodeBoolMap = context::CDHashMap<Node, bool>;
168		using NodeExtReducedIdMap = context::CDHashMap<Node, ExtReducedId>;
169		using NodeSet = context::CDHashSet<Node>;
170
171		public:
172		/** constructor
173		*
174		* If cacheEnabled is false, we do not cache results of getSubstitutedTerm.
175		*/
176		ExtTheory(ExtTheoryCallback& p,
177		context::Context* c,
178		context::UserContext* u,
179		OutputChannel& out);
180	14972	virtual ~ExtTheory() {}
181		/** Tells this class to treat terms with Kind k as extended functions */
182	217726	void addFunctionKind(Kind k) { d_extf_kind[k] = true; }
183		/** Is kind k treated as an extended function by this class? */
184	64	bool hasFunctionKind(Kind k) const
185		{
186	64	return d_extf_kind.find(k) != d_extf_kind.end();
187		}
188		/** register term
189		*
190		* Registers term n with this class. Adds n to the set of extended function
191		* terms known by this class (d_ext_func_terms) if n is an extended function,
192		* that is, if addFunctionKind( n.getKind() ) was called.
193		*/
194		void registerTerm(Node n);
195		/** set n as reduced/inactive
196		*
197		* If satDep = false, then n remains inactive in the duration of this
198		* user-context level
199		*/
200		void markReduced(Node n, ExtReducedId rid, bool satDep = true);
201		/** getSubstitutedTerms
202		*
203		* input : effort, terms
204		* output : sterms, exp, where ( exp[i] => terms[i] = sterms[i] ) for all i.
205		*
206		* For each i, sterms[i] = term[i] * sigma for some "derivable substitution"
207		* sigma. We obtain derivable substitutions and their explanations via calls
208		* to the underlying theory's Theory::getCurrentSubstitution method.
209		*/
210		void getSubstitutedTerms(int effort,
211		const std::vector<Node>& terms,
212		std::vector<Node>& sterms,
213		std::vector<std::vector<Node> >& exp);
214		/**
215		* Same as above, but for a single term. We return the substituted form of
216		* term and add its explanation to exp.
217		*/
218		Node getSubstitutedTerm(int effort, Node term, std::vector<Node>& exp);
219		/** doInferences
220		*
221		* This function performs "context-dependent simplification". The method takes
222		* as input:
223		* effort: an identifier used to determine which terms we reduce and the
224		* form of the derivable substitution we will use,
225		* terms: the set of terms to simplify,
226		* batch: if this flag is true, we send lemmas for all terms; if it is false
227		* we send a lemma for the first applicable term.
228		*
229		* Sends rewriting lemmas of the form ( exp => t = c ) where t is in terms
230		* and c is a constant, c = rewrite( t*sigma ) where exp \|= sigma. These
231		* lemmas are determined by asking the underlying theory for a derivable
232		* substitution (through getCurrentSubstitution with getSubstitutedTerm)
233		* above, applying this substitution to terms in terms, rewriting
234		* the result and checking with the theory whether the resulting term is
235		* in reduced form (isExtfReduced).
236		*
237		* This method adds the extended terms that are still active to nred, and
238		* returns true if and only if a lemma of the above form was sent.
239		*/
240		bool doInferences(int effort,
241		const std::vector<Node>& terms,
242		std::vector<Node>& nred,
243		bool batch = true);
244		/**
245		* Calls the above function, where terms is getActive(), the set of currently
246		* active terms.
247		*/
248		bool doInferences(int effort, std::vector<Node>& nred, bool batch = true);
249		/** doReductions
250		*
251		* This method has the same interface as doInferences. In contrast to
252		* doInfereces, this method will send reduction lemmas of the form ( t = t' )
253		* where t is in terms and t' is an equivalent reduced term.
254		*/
255		bool doReductions(int effort,
256		const std::vector<Node>& terms,
257		std::vector<Node>& nred,
258		bool batch = true);
259		bool doReductions(int effort, std::vector<Node>& nred, bool batch = true);
260
261		/** get the set of all extended function terms from d_ext_func_terms */
262		void getTerms(std::vector<Node>& terms);
263		/** is there at least one active extended function term? */
264		bool hasActiveTerm() const;
265		/** is n an active extended function term? */
266		bool isActive(Node n) const;
267		/**
268		* Same as above, but rid is updated to the reason if this method returns
269		* false.
270		*/
271		bool isActive(Node n, ExtReducedId& rid) const;
272		/** get the set of active terms from d_ext_func_terms */
273		std::vector<Node> getActive() const;
274		/** get the set of active terms from d_ext_func_terms of kind k */
275		std::vector<Node> getActive(Kind k) const;
276
277		private:
278		/** returns the set of variable subterms of n */
279		static std::vector<Node> collectVars(Node n);
280		/** is n context dependent inactive? */
281		bool isContextIndependentInactive(Node n) const;
282		/**
283		* Same as above, but rid is updated to the reason if this method returns
284		* true.
285		*/
286		bool isContextIndependentInactive(Node n, ExtReducedId& rid) const;
287		/** do inferences internal */
288		bool doInferencesInternal(int effort,
289		const std::vector<Node>& terms,
290		std::vector<Node>& nred,
291		bool batch,
292		bool isRed);
293		/** send lemma on the output channel */
294		bool sendLemma(Node lem, bool preprocess = false);
295		/** reference to the callback */
296		ExtTheoryCallback& d_parent;
297		/** Reference to the output channel we are using */
298		OutputChannel& d_out;
299		/** the true node */
300		Node d_true;
301		/** extended function terms, map to whether they are active */
302		NodeBoolMap d_ext_func_terms;
303		/** mapping to why extended function terms are inactive */
304		NodeExtReducedIdMap d_extfExtReducedIdMap;
305		/**
306		* The set of terms from d_ext_func_terms that are SAT-context-independent
307		* inactive. For instance, a term t is SAT-context-independent inactive if
308		* a reduction lemma of the form t = t' was added in this user-context level.
309		*/
310		NodeExtReducedIdMap d_ci_inactive;
311		/**
312		* Watched term for checking if any non-reduced extended functions exist.
313		* This is an arbitrary active member of d_ext_func_terms.
314		*/
315		context::CDO<Node> d_has_extf;
316		/** the set of kinds we are treated as extended functions */
317		std::map<Kind, bool> d_extf_kind;
318		/** information for each term in d_ext_func_terms */
319	19396	class ExtfInfo
320		{
321		public:
322		/** all variables in this term */
323		std::vector<Node> d_vars;
324		};
325		std::map<Node, ExtfInfo> d_extf_info;
326
327		// cache of all lemmas sent
328		NodeSet d_lemmas;
329		NodeSet d_pp_lemmas;
330		};
331
332		} // namespace theory
333		} // namespace cvc5
334
335		#endif /* CVC5__THEORY__EXT_THEORY_H */