Hi,

I solicit a criticism and possible better solutions to the following
problem.

I have a nonmodifyable C++ class

class T
{
   public:
     Color* getColor(const char* name);
     void     setColor(const char* name, const Color* value);

     Line*  getLine(const char* name);
     void     setLine(const char* name, const Line* value);

     //and so on
};
with a bunch of classes Color, Line, etc.

I want pretend in Python interface that T has bunch of attributes 'color',
'line', etc.
that behave like mappings each, i.e. I want to be able to say in Python:

t=T()
t.color["a"]=Color(...)
print t.line["b"]

For that purpose I created helper classes and generator functions

class TColorHelper
{
    T& _t;
public:
    TColorHelper(T& t) : _t(t) {}
    Color* get(const char* name) { return _t.getColor(name); }
    void     set(const char* name, const Color* value)
{_t.setColor(name,value);}
};
TColorHelper color(T& t) { return TColorHelper(t); }

class TLineHelper {...}; line(){...} //and so on for each property

wrap them:

 class_<TColorHelper> ("TColorHelper", no_init)
  .def("__getitem__", &TColorHelper::get, return_internal_ref<> ())
  .def("__setitem__", &TColorHelper::set)
  ;
//...
class_<T> ("T")
  .add_property("color", color)
  .add_property("line", line)
  ;

which works fairly well.

So what do think about it?
Maybe you have had similar problem and solved it differently.
I appreciate your comments.

Thanks,
Mike




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