Question

我很难找到代码项目的问题，该代码项目由四个文件组成：

GiftRegistry.cpp：

#include "GiftRegistry.h"
#include "LinkList/LinkedList.h"
#include "LinkList/LinkedList.cpp"
#include <iostream>

template<class ItemType>
GiftRegistry<ItemType>::GiftRegistry() : giftRegistry(new LinkedList<ItemType>())
{
}

template<class ItemType>
bool GiftRegistry<ItemType>::addGift(const ItemType& gift, int desiredRank)
{
    if(giftRegistry->insert(desiredRank, gift))
    {
        return true;
    }
    else{
        return false;
    }
}

template<class ItemType>
void GiftRegistry<ItemType>::moveGift(int curPos, int newPos)
{
    if(giftRegistry->isEmpty())
    {
        ItemType itemToMove = giftRegistry->getEntry(curPos);

        if(giftRegistry->insert(newPos, itemToMove))
        {
            cout << "Gift moved successfully!";
        }
        if(giftRegistry->remove(curPos))
        {
            cout << "Gift removed successfully";
        }
        else{
            cout << "Operation failed. Please examine input.";
        }
    }
}

template<class ItemType>
bool GiftRegistry<ItemType>::removeGift(int position)
{
    if(giftRegistry->isEmpty())
    {
        if(giftRegistry->remove(position))
        {
            return true;
        }

    }
    else
    {
        return false;
    }
}

template<class ItemType>
void GiftRegistry<ItemType>::showRegistry()
{
    for(int i = 1; i < giftRegistry->getLength(); i++)
    {
        ItemType itemToPrint = giftRegistry->getEntry(i);
        std::cout << i + "." + itemToPrint;
    }
}

main.cpp中：

#include "GiftRegistry.cpp"
//#include "LinkList/LinkedList.cpp"
#include <iostream>
#include <string>

using namespace std;

int main()
{
    ListInterface<string>* listPtr = new LinkedList<string>();
    //RegistryInterface<string>* weddingRegistry = new GiftRegistry<string>();
    string gift = "hello there";
    listPtr->insert(1, gift);
    cout << listPtr->getEntry(1);
//    string gift = "Box of rocks";
//
//    RegistryInterface<string>* weddingRegistry = new GiftRegistry<string>();
//    if(weddingRegistry->addGift(gift, 1))
//    {
//        cout << "Added item " + gift;
//        weddingRegistry->showRegistry();
//    }
//    else
//    {
//        cout << "Failed to add item. Error.";
//    }
    //weddingRegistry->showRegistry();

    return 0;
}

GiftRegistry.h：

#ifndef Gift_Registry_
#define Gift_Registry_

#include "RegistryInterface.h"
#include "C:\Users\Austin\Documents\LinkList\LinkedList.h"
using namespace std;

template<class ItemType>
class GiftRegistry : public RegistryInterface<ItemType>
{
private:
    LinkedList<ItemType>* giftRegistry;

public:
    string CustomerName;
    string EventName;
    GiftRegistry();

    bool addGift(const ItemType& gift, int desiredRank);
    void moveGift(int curPos, int newPos);
    bool removeGift(int position);
    void showRegistry();

    virtual ~GiftRegistry();
};

#endif // _GiftRegistry_

RegistryInterface.h：

#ifndef REGISTRY_INTERFACE_
#define REGISTRY_INTERFACE_

template<class ItemType>
class RegistryInterface
{
public:
    /** Adds gift to the gift registry
    @post Add was successful
    @param gift The gift to be added to the registry.
    @param giftRank The rank to be attributed to the gift. Also determines the point of insertion for the gift.
    @return 'True' if addition was successful, 'false' if item already exists in the list
    **/
    virtual bool addGift(const ItemType& gift, int giftRank) = 0;

    /** Moves the gift to the user-desired location / priority
    @pre List is not empty
    @param currentPosition The current position of the gift to be moved.
    @param desiredPosition The new position
    **/
    virtual void moveGift(int currentPosition, int desiredPosition) = 0;

    /** Removes the specified item from the List
    @pre List is not empty
    @post Item was removed
    @param position The index of the item to be removed
    @return 'True' if gift was removed, 'False' if not
    **/
    virtual bool removeGift(int position) = 0;


    /** Prints the registry contents and displays them by most wanted to least wanted
    @pre List is not empty
    **/
    virtual void showRegistry() = 0;

    /** Destroys this registry and frees its assigned memory.
    **/
    virtual ~RegistryInterface() { }
};
#endif // REGISTRY_INTERFACE_

我正在使用Code :: Blocks 16.01并遵守C ++ 11标准。运行＆＃39; main.cpp＆＃39;时会出现问题。文件，导致出现以下错误：

|| === Build：GiftList中的Debug（编译器：GNU GCC编译器）=== | obj \ Debug \ main.o ||函数ZNK10LinkedListISsE8getEntryEi':| C:\Users\Arralan\Documents\LinkList\LinkedList.cpp|121|undefined reference to PreconditionViolatedException :: PreconditionViolatedException（std :: string const＆amp;）＆＃39; | obj \ Debug \ main.o ||函数ZN10LinkedListISsE7replaceEiRKSs':| C:\Users\Arralan\Documents\LinkList\LinkedList.cpp|140|undefined reference to PreconditionViolatedException :: PreconditionViolatedException（std :: string const＆amp;）＆＃39; | ||错误：ld返回1退出状态| || ===构建失败：3个错误，0个警告（0分钟，0秒（秒））=== |

我是数据结构的新手，这个问题已让我挂了两天了。任何帮助或指导将不胜感激，但请记住，这是一个家庭作业。

＆＃34; LinkList＆＃34;中的代码没有错误，并且在其单独的项目中按预期运行，但在从另一个项目引用时表现得很奇怪。我相信这个问题可能与我的#include＆＃39;声明。

编辑：问题是由#inc; #include＆＃39;这在这个独特的例子中是必要的。我发现的解决方案，无论是否最好，都是通过＆＃39; #include＆＃39;：＆＃34; LinkList / PreconditionViolatedException.cpp＆＃34;添加此路径。将此行添加到我的＆＃39; main.cpp＆＃39;后，错误已停止显示。

未定义的引用＆quot; PreconditionViolatedException :: PreconditionViolatedException（std :: string const＆amp;）＆＃39;

0 个答案: