如何实现C ++的多重继承？ [英] How is C++'s multiple inheritance implemented?

问题描述

单继承容易实现。例如，在C中，继承可以被模拟为：

  struct Base {int a; } 
 struct Descendant {Base parent; int b; } 
  

但是使用多重继承，编译器必须在新构造的类中安排多个父节点。

我看到的问题是：如果父母是以AB或BA，或者甚至是其他方式安排的？然后，如果我做一个演员：

  SecondBase * base =（SecondBase *）& object_with_base1_and_base2_parents; 
  

编译器必须考虑是否更改原始指针。

解决方案

来自C ++的创建者的以下文章描述了多重继承的可能实现： / p>

C ++的多重继承

a> -Bjarne Stroustrup

Single inheritance is easy to implement. For example, in C, the inheritance can be simulated as:

struct Base { int a; }
struct Descendant { Base parent; int b; }

But with multiple inheritance, the compiler has to arrange multiple parents inside newly constructed class. How is it done?

The problem I see arising is: should the parents be arranged in AB or BA, or maybe even other way? And then, if I do a cast:

SecondBase * base = (SecondBase *) &object_with_base1_and_base2_parents;

The compiler must consider whether to alter or not the original pointer. Similar tricky things are required with virtuals.

解决方案

The following paper from the creator of C++ describes a possible implementation of multiple inheritance:

Multiple Inheritance for C++ - Bjarne Stroustrup

这篇关于如何实现C ++的多重继承？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！