text: /*
   * Copyright (C) 2015 David Perfors
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the “Software”), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   * 
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   * 
   * THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  
  #ifndef _CALCULATOR_CALCULATORVISITOR_H_
  #define _CALCULATOR_CALCULATORVISITOR_H_
  
  #include "expressions.h"
  #include <string>
  #include <map>
  
  namespace calculator
  {
      struct CalculatorVisitor : ExpressionVisitor
      {
          CalculatorVisitor(std::map<std::string, double>&);
          void visit(NumberExpression&);
          void visit(IdentifierExpression&);
          void visit(AssignmentExpression&);
          void visit(BinaryOperatorExpression&);
  
          double result() const { return result_; }
      private:
          double result_;
          std::map<std::string, double>& variables_;
      };
  }
  
  #endif
  