映射集/获取请求到C ++类/结构的变化 [英] map set/get requests into C++ class/structure changes

问题描述

我想弄明白这里最好的方法是什么。基本上我有一个系统，我收到外部请求，以设置/获取我的模型中的值。问题是我的模型由C ++类组成，可以嵌套，而请求是简单的（键，值）对。

例如：

  struct Foo {
 void setX（int x）; 
 int getX（）const; 
 
 struct Boo {
 void setY（float y）; 
 float getY（）const; 
}：
}; 
  

如果我收到一个请求 set（y，21） code>给定的元素e，然后我需要执行的动作将不同，取决于是否foo和boo已经存在。不得不照顾每个属性的不同的可能性将写入大量的代码。

在重新发明轮子之前，我想知道是否已经有一个库或者C ++中的一个众所周知的技术，它允许以一种通用的方式将此平面操作映射到C ++结构（可以嵌套）中的变化。

解决方案

Boost有此属性的属性地图。

• http://www.boost.org/doc/ libs / 1_57_0 / libs / property_map / doc / property_map.html

>

  get（map，key）
 put（pmap，key，val）
  
 
 
 
对于价值可读的地图，您还可以获得样式访问
 $ 
  pmap [key]; 
 pmap [key] = newval; //如果不是const / readonly 
  
您可以使用现有的属性映射适配器：
 
 
 
 
 
  identity_property_map 和 typed_identity_property_map  
 
 
  function_property_map  
 
 
  iterator_property_map  
 
 
  shared_array_property_map  
 
 
  associative_property_map  
 
 
  const_associative_property_map  
 
 
  vector_property_map  
 
 
  ref_property_map  
 
 
  static_property_map  
 
 
  transform_value_property_map  
 
 
  compose_property_map  
 
 
 
 
 
或写自定义。
 
 
 
甚至还有   dynamic_property_map   ，如下所示：
  put（age，properties，fred，new_age）; 
 put（gpa，properties，fred，new_gpa）; 
  
请注意 age 和 gpa 可以存储在任何地方（甚至可能需要一个web请求），但访问的差异被位于之间的属性界面抽象化。
 
 
 
 
 
 
我的答案中的示例：
 
 
 
 
 
 可以有几个一个图表的边缘权重属性映射BOOST？ 
 
 
 使用BiMap和Boost多索引容器来存储属性
 
 
 
I'm trying to figure out what is the best approach here. Basically I have a system where I receive external requests in order to set/get values in my model. The problem is that my model consists on C++ classes, which can be nested, whereas the requests are simple (key, value) pairs.

For example:
struct Foo {
    void setX(int x);
    int getX() const;

    struct Boo {
        void setY(float y);
        float getY() const;
    }:
};
If I receive a request that says set(y, 21) for a given element e, then the actions I need to perform will be different depending on whether or not foo and boo already exist. Having to take care of the different possibilities for each property would end up in writing a lot of code.

Before reinventing the wheel, I was wondering if there is already a library or a well-known technique in C++ that allows mapping this flat actions into changes in C++ structures (which can be nested) in a generic way.

Thanks
解决方案
Boost has Property Maps for this purpose.


http://www.boost.org/doc/libs/1_57_0/libs/property_map/doc/property_map.html


The most elementary interface it exposes is
get(map, key)
put(pmap, key, val)
For lvalue/readable maps you can also get indexer style access 
pmap[key];
pmap[key] = newval; // if not const/readonly
You can a existing property map adaptors:


identity_property_map and typed_identity_property_map 
function_property_map 
iterator_property_map
shared_array_property_map
associative_property_map
const_associative_property_map
vector_property_map
ref_property_map 
static_property_map 
transform_value_property_map 
compose_property_map 


or write custom ones.

There is even a dynamic_property_map that looks like this, in practice:
put("age",properties,fred,new_age);
put("gpa",properties,fred,new_gpa);
Note that age and gpa could be stored anywhere (even requiring a web-request, perhaps) but the difference in access is abstracted away by the properymap interface that sits in between.



Samples from my answers:


Is it possible to have several edge weight property maps for one graph BOOST?
Cut set of a graph, Boost Graph Library using a BiMap and a Boost Multi Index container to store the properties


                        
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