唯一的类类型ID，它是安全的并且跨库的边界 [英] Unique class type Id that is safe and holds across library boundaries

问题描述

我会感谢任何帮助，因为C ++不是我的主要语言。

我有一个模板类，在多个库中派生。我试图找出一种方法来唯一地分配一个id int到每个派生类。我需要能够通过静态方法，即

  
 template< class DERIVED> 
 class Foo 
 {
 public：
 static int s_id（）
 {
 // DERIVED的返回ID是唯一的
} 
 // ... 
}; 
 
  
谢谢！
解决方案
这是我最后做的。如果您有任何意见（利弊），请通知我们。
 
 
 
 
  
 template< class DERIVED> 
 class Foo 
 {
 public：
 static const char * name（）; //派生类将实现，简单地
 
 //返回它们的类名
 static int s_id（）
 {
 static const int id = Id_factory :: get_instance ） - > get_id（name（））; 
 return id; 
} 
 // ... 
}; 
 
  
 
 
 
基本上，在进行字符串比较而不是指针比较之后，这在速度上是不理想的，但我做了id静态const，所以它只需要为每个DERIVED计算一次。
 
I would appreciate any help as C++ is not my primary language.

I have a template class that is derived in multiple libraries. I am trying to figure out a way to uniquely assign an id int to each derived class. I need to be able to do it from a static method though, ie.


template < class DERIVED >
class Foo
{
public:
    static int s_id()
    {
        // return id unique for DERIVED
    }
    // ...
};

Thank you!
解决方案
Here's what I ended up doing. If you have any feedback (pros, cons) please let me know.


template < class DERIVED >
class Foo
{
public:
    static const char* name(); // Derived classes will implement, simply

                               // returning their class name
    static int s_id()
    {
        static const int id = Id_factory::get_instance()->get_id(name());
        return id;
    }
    // ...
};


Essentially the id will be assigned after doing a string comparison rather than a pointer comparison. This is not ideal in terms of speed, but I made the id static const so it will only have to calculate once for each DERIVED.

                        
这篇关于唯一的类类型ID，它是安全的并且跨库的边界的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！