text: 
  #ifndef __BooleanValue_h__
  #define __BooleanValue_h__
  
  #include "Value.h"
  #include "ValueException.h"
  #include "StringValue.h"
  
  /**
   * True or false.
   */
  class BooleanValue: public Value {
  private:
    bool value;
  public:
    BooleanValue(bool value);
    BooleanValue(const Token &t, bool value);
    virtual ~BooleanValue();
  
    bool getValue() const;
    void setValue(bool value);
  
    virtual Value* add(const Value &v) const;
    virtual Value* substract(const Value &v) const;
    virtual Value* multiply(const Value &v) const;
    virtual Value* divide(const Value &v) const;
  
    virtual BooleanValue* equals(const Value &v) const;
    virtual BooleanValue* lessThan(const Value &v) const;
  };
  #endif
    
  