class IncentiveAccumulator
{
public:
    template<class WrappedScope, class ValueType, class NameTag>
    void operator()(ValueType& attribute, NameTag nameTag, WrappedScope wrappedScope)
    {
        typedef typename PartOfIncentiveProgram<NameTag>::type CouldBePartOfIncentives;
        accumulateValue(attribute, nameTag,wrappedScope, CouldBePartOfIncentives());
    }
    std::string result()const
    {
        return incentives_.str();
    }
private:
    template<class WrappedScope, class Value, class NameTag> void 
    accumulateValue(Value& incentive, NameTag nameTag, WrappedScope, Applies)
    {
        typedef WrappedScope::type Scope;
        incentives_ << Scope::getClassName() << "." << Scope::getAttributeName(nameTag)<< ":";
        incentives_ << incentive << "\t";
    }
    template<class WrappedScope, class Value, class NameTag> void 
    accumulateValue(Value&,NameTag, WrappedScope,DoesNotApply)
    { }
    std::stringstream incentives_;
};

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