[C++-sig] create a python object from scratch in boost.python?

[Stefan Seefeld]

On 01/21/2014 01:52 PM, Gary Oberbrunner wrote:
>
> ----- Original Message -----
>> From: "Stefan Seefeld" <stefan at seefeld.name>
> ...
>> It seems what you really want is a way for your C++ code to
>> manipulate pure Python objects, without any automatic type conversion.
> Yes!
>
>> So the cleanest way to do that would be to use the above definition of
>> the "Effect" class (in Python), import that into your C++ runtime
>> (via bpl::import()), and then instantiate an "Effect" object with your
>> pre-defined dict object.
> I'm trying to do this in a boost python extension, so it has to be all in C++.  If I have to wrap some python around it, it'll become a bit too heavyweight.  

Have a look at the attached code; I don't think that counts as
heavy-weight. In particular, trying to do the same without  embedding a
little "script" would be just more cumbersome, if it worked at all.


> I'd love to do what you suggest above, if it can be done all in C++.  I think all I need is a way to create, in C++, an empty Python class object with a __dict__.  Then, as you say, I can add attributes to it (at least I think I should be able to - but I'm not sure how far the boost.python world goes).

Compile the attached as a stand-alone app. I think it demonstrates what
you want, so you should be able to easily adjust it to your use-case.

        Stefan


-- 

      ...ich hab' noch einen Koffer in Berlin...

-------------- next part --------------
A non-text attachment was scrubbed...
Name: bpl2.cc
Type: text/x-c++src
Size: 889 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/cplusplus-sig/attachments/20140121/39611e43/attachment.cc>