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diff --git a/src/expr/term_context_stack.h b/src/expr/term_context_stack.h
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+/*********************                                                        */
+/*! \file term_context_stack.h
+ ** \verbatim
+ ** Top contributors (to current version):
+ **   Andrew Reynolds
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2020 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 Term context
+ **/
+
+#include "cvc4_private.h"
+
+#ifndef CVC4__EXPR__TERM_CONTEXT_STACK_H
+#define CVC4__EXPR__TERM_CONTEXT_STACK_H
+
+#include "expr/term_context_node.h"
+
+namespace CVC4 {
+
+/**
+ * A stack for term-context-sensitive terms. Its main advantage is that
+ * it does not rely on explicit construction of TCtxNode for efficiency.
+ */
+class TCtxStack
+{
+ public:
+  TCtxStack(const TermContext* tctx);
+  virtual ~TCtxStack() {}
+  /** Push t to the stack */
+  void pushInitial(Node t);
+  /**
+   * Push all children of t to the stack, where tval is the term context hash
+   * of t. */
+  void pushChildren(Node t, uint32_t tval);
+  /**
+   * Push the child of t with the given index to the stack, where tval is
+   * the term context hash of t.
+   */
+  void pushChild(Node t, uint32_t tval, size_t index);
+  /** Push t to the stack with term context hash tval. */
+  void push(Node t, uint32_t tval);
+  /** Pop a term from the context */
+  void pop();
+  /** Clear the stack */
+  void clear();
+  /** Return the size of the stack */
+  size_t size() const;
+  /** Return true if the stack is empty */
+  bool empty() const;
+  /** Get the current stack element */
+  std::pair<Node, uint32_t> getCurrent() const;
+  /** Get the current stack element, node version */
+  TCtxNode getCurrentNode() const;
+
+ private:
+  /** The stack */
+  std::vector<std::pair<Node, uint32_t>> d_stack;
+  /** The term context */
+  const TermContext* d_tctx;
+};
+
+}  // namespace CVC4
+
+#endif /* CVC4__EXPR__TERM_CONTEXT_STACK_H */