////////////////////////////////////////////////////////////////////////////////
/// DISCLAIMER
///
/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///     http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Jan Steemann
////////////////////////////////////////////////////////////////////////////////

#ifndef ARANGOD_AQL_EXPRESSION_CONTEXT_H
#define ARANGOD_AQL_EXPRESSION_CONTEXT_H 1

#include "Basics/Common.h"
#include "Aql/types.h"

namespace arangodb {
namespace aql {

struct AqlValue;
struct Variable;

class ExpressionContext {
 public:
  ExpressionContext() {}

  virtual ~ExpressionContext() {}

  virtual size_t numRegisters() const = 0;

  virtual AqlValue const& getRegisterValue(size_t i) const = 0;

  virtual Variable const* getVariable(size_t i) const = 0;

  virtual AqlValue getVariableValue(Variable const* variable, bool doCopy, bool& mustDestroy) const = 0;
};
}
}
#endif