相当于Python getattr的C ++ [英] C++ equivalent of Python getattr

问题描述

在python中，有一个名为getattr的函数，如下所示:

In python, there is a function called getattr which would look like this:

class MyObject():
    def __init__(self):
        self.xyz = 4

obj = MyObject()
getattr(obj, 'xyz')

getattr的调用将返回4.

where the call to getattr would return 4.

在C ++(不是Visual C ++)中是否有类似的方法?

Is there a similar way to do this in C++ (Not Visual C++)?

是否有任何具有此功能的库，可以在其中使用字符串查找对象的成员变量?

Are there any libraries that have this functionality where I can lookup an object's member variables using a string?

我试图找到一种方法来查找我无法更改的C ++类中的公共数据成员.因此，我无法使用映射将字符串文字映射到值.也许像是用宏取消字符串化"?

I am trying to find a way to look up public data members in a C++ class that I cannot change. So I cannot use a map to map string literals to values. Maybe like an 'unstringify' with macros?

推荐答案

您要的内容通常称为自省.

C ++语言本身不支持自省.您可以模拟它，但这就是它的范围.

The C++ language does not support introspection by itself. You can emulate it, but that is the extent of it.

您提出的API中还存在另一个问题:您将如何制定方法的返回类型? 是一个boost::any类，适合于存储该项目，但是如果您仍然不知道其类型，将无法对其进行任何有用的处理.

There is also another issue in the API you propose: how would you formulate the return type of your method ? There is a boost::any class that would be suitable to store the item, but you would not be able to anything useful with it if you do not know its type anyway.

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