c++ - Visual C++ 模板语法错误

Question

我有一个头文件...

#include <SFML\Graphics.hpp>
#include <SFML\Graphics\Drawable.hpp>
#include <SFML\System.hpp>
#include <iostream>

#ifndef _SPRITE_H_
#define _SPRITE_H_

namespace Engine 
{
    template <class T>
    class Sprite
    {
        sf::Vector2<T> * vector;
        sf::Sprite * sprite;

    public:
        Sprite(sf::Vector2<T> vect, sf::Sprite spr) 
        { 
            this->sprite = spr;
            this->vector = vect;            
        }
        ~Sprite();
        bool Draw(T x, T y, T rotate = 0);
        sf::Image GetImage()
        {
            return this->sprite->GetImage();
        }
    };
};

#endif _SPRITE_H_

还有一个源文件...

#include <SFML/Graphics.hpp>
#include <SFML/Config.hpp>

#include "sprite.h"

template <typename T>
Sprite(sf::Vector2<T> vector, sf::Sprite sprite) 
{
    this->sprite = sprite;
    this->vector = vector;
}

template <typename T>
bool Draw(T x, T y, T rotate) 
{
    return false;
}

在 VS 2010 中，当我编译 VC++ 时出现以下错误:

Error   2   error C2143: syntax error : missing ';' before '<'  c:\users\owner\documents\visual studio 2010\projects\engine2\engine2\sprite.cpp 7   1   Engine2
Error   3   error C4430: missing type specifier - int assumed. Note: C++ does not support default-int   c:\users\owner\documents\visual studio 2010\projects\engine2\engine2\sprite.cpp 7   1   Engine2
Error   4   error C2988: unrecognizable template declaration/definition c:\users\owner\documents\visual studio 2010\projects\engine2\engine2\sprite.cpp 7   1   Engine2
Error   5   error C2059: syntax error : '<' c:\users\owner\documents\visual studio 2010\projects\engine2\engine2\sprite.cpp 7   1   Engine2
Error   6   error C2059: syntax error : ')' c:\users\owner\documents\visual studio 2010\projects\engine2\engine2\sprite.cpp 7   1   Engine2
Error   7   error C2143: syntax error : missing ';' before '{'  c:\users\owner\documents\visual studio 2010\projects\engine2\engine2\sprite.cpp 15  1   Engine2
Error   8   error C2447: '{' : missing function header (old-style formal list?) c:\users\owner\documents\visual studio 2010\projects\engine2\engine2\sprite.cpp 15  1   Engine2

我完全是 C++ 的菜鸟(来自 C#)，并且在编译这个简单的文件时遇到了问题，作为一种至少在我继续之前学习语法的方法。如您所见，我所要做的就是将头文件中的模板引用到源文件中，以便模板引用影响我的所有方法。

我做错了什么？我试图理解这些编译器消息，但我无法解密它们。

更新

遵循建议:处理几乎所有事情，除了这个:

Error   1   error C2995: 'Engine::Sprite<T>::Sprite(sf::Vector2<T>,sf::Sprite)' : function template has already been defined    c:\users\owner\documents\visual studio 2010\projects\engine2\engine2\sprite.cpp 12  1   Engine2

Answer 1

因为Sprite在Engine里面，所以应该是

template <typename T>
Engine::Sprite<T>::Sprite(sf::Vector2<T> vector, sf::Sprite sprite)
{ ... }

和

template <typename T>
bool Engine::Sprite<T>::Draw(T x, T y, T rotate)
{
    return false;
}

或者，正如@jli 所建议的那样，也将它放在命名空间 Engine 中:

namespace Engine {
    template <typename T>
    Sprite<T>::Sprite(sf::Vector2<T> vector, sf::Sprite sprite)
    { ... }

    template <typename T>
    bool Sprite<T>::Draw(T x, T y, T rotate)
    {
        return false;
    }
}