问错误:没有名为‘current_date’的成员

EN

#ifndef WAREHOUSE_H
#define WAREHOUSE_H
#include<string>
#include<map>
#include "dates.h"

namespace a4
{
 class warehouse
 {
    public:
        warehouse(std::string name, std::string start_date);

    private:
        std::string name;
        std::string busiest_day;
        int most_transactions;
        std::map<std::string, a4::food> items;
        dates current_date;
        void next_day();
 };
}
 #endif

#include "warehouse.h"
#include "dates.h"
namespace a4
{
 //constructor
 warehouse::warehouse(std::string name, std::string start_date)
 {
     this->current_date = new dates(start_date);
 }
 void warehouse::next_day()
 {
     this->current_date.next_day();
 }
}

warehouse.cc: In constructor ‘a4::warehouse::warehouse(std::string, std::string)’:
warehouse.cc:8: error: ‘class a4::warehouse’ has no member named ‘current_date’
warehouse.cc: In member function ‘void a4::warehouse::next_day()’:
warehouse.cc:12: error: ‘class a4::warehouse’ has no member named ‘current_date’