Question

在尝试编译为代码时，我收到以下错误：

Error   5   error LNK1120: 2 unresolved externals   C:\Users\---\VSworkspace\Work\Debug\AbstractTypes.exe   AbstractTypes
Error   3   error LNK2019: unresolved external symbol "private: void __thiscall Vec<int>::create(void)" (?create@?$Vec@H@@AAEXXZ) referenced in function "public: __thiscall Vec<int>::Vec<int>(void)" (??0?$Vec@H@@QAE@XZ) C:\Users\---\VSworkspace\Work\AbstractTypes\main.obj    AbstractTypes
Error   4   error LNK2019: unresolved external symbol "private: void __thiscall Vec<int>::uncreate(void)" (?uncreate@?$Vec@H@@AAEXXZ) referenced in function "public: __thiscall Vec<int>::~Vec<int>(void)" (??1?$Vec@H@@QAE@XZ)    C:\Users\---\VSworkspace\Work\AbstractTypes\main.obj    AbstractTypes

这是代码

Vec.h

#pragma once
#ifndef GUARD_VEC_H
#define GUARD_VEC_H
#include <memory>
#include <cstddef> //FOR: size_type

template<class T> class Vec {
    public: //interface
        typedef T* iterator;
        typedef const T* const_iterator;
        typedef size_t size_type;
        typedef T value_type;

        Vec() { create(); }
        explicit Vec(size_type n, const T& val = T()) { create(n, val); }
        Vec(const Vec& v) { create(v.begin(), v.end()); }

        Vec& operator = (const Vec&);
        ~Vec() { uncreate(); }
        T& operator[] (size_type i) { return data[i]; }
        const T& operator[] (size_type i) const { return data[i]; }

        void push_back(const T& t) {
            if (avail == limit)
                grow();
            unchecked_append(t);
        }

        size_type size() const { return avail - data; }

        iterator begin() { return data; }
        const_iterator begin() const { return data; }

        iterator end() { return avail; }
        const_iterator end() const { return avail;  }
    private: //implementation
        iterator data;
        iterator avail;
        iterator limit;

        std::allocator<T> alloc;

        void create();
        void create(size_type, const T&);
        void create(const_iterator, const_iterator);

        void uncreate();

        void grow();
        void unchecked_append(const T&);
};


#endif

Vec.cpp

#include "Vec.h";
#include <memory>
template <class T> void Vec<T>::create()
{
    data = avail = limit = 0;
}

template <class T> void Vec<T>::create(size_type n, const T& val)
{
    data = alloc.allocate(n);
    limit = avail = data + n;
    uninitialized_fill(data, limit, val);
}

template <class T>
void Vec<T>::create(const_iterator i, const_iterator j){
    data = alloc.allocate(j- i);
    limit = avail = uninitialized_copy(i, j, data);
}

template <class T> void Vec<T>::uncreate()
{
    if (data){
        iterator it = avail;
        while (it != data)
            alloc.destroy(--it);
        alloc.deallocate(data, limit - data);
    }
    data = limit = avail = 0;
}

template <class T> void Vec<T>::grow()
{
    size_type new_size = max(2 * (limit - data), ptrdiff_t(1));
    iterator new_data = alloc.allocate(new_size);
    iterator new_avail = uninitialized_copy(data, avail, new_data);

    uncreate();

    data = new_data;
    avail = new_avail;
    limit = data + new_size;
}

template <class T> void Vec<T>::unchecked_append(const T& val)
{
    alloc.construct(avail++, val);
}

* Main.cpp的**

#include "Vec.h"
#include <iostream>

int main(){
    Vec<int> vector;
    return 0;
}

我对这个错误做了一些研究，可能与这个模板类的事实有关。我祈祷这可能不是一个愚蠢的错误。非常感谢，谢谢。

模板类中未解析的外部符号？

0 个答案: