[C++-sig] Duplicate class and method definition

[Stefan Seefeld]

On 02/22/2010 09:45 AM, André Prins wrote:
> Hi All,
>
> Recently, I had some problems with a duplicate method and class
> definition begin accepted by boost::python (version 1.41 on MSVC).
> Consider the following c++-code, which declares a class Foo twice, but
> with different bindings for the same function.
>    

[...]

> It is obvious that this is not the intended use of Boost-python, but I
> am wondering: why does it assert at runtime without the noncopyable
> and why does it "more or less work" with the boost::noncopyable. And
> is there a method to detect such multiple definitions of the same
> class.
>    

For the first two questions: I would suggest you consider the code 
"ill-formed" and the behavior "undefined", so there isn't any need to 
(second-)guess what the library is doing, and why things appear to be 
working in one case but not the other.

As to the last question: I suggest you submit a request for enhancement 
for this. I'm pretty sure the library can detect this, and raise an 
appropriate exception. Alternatively, if it is decided that the above is 
a valuable use-case to support, the library needs to be improved to 
support it.

I'm saying that because recently we had a discussion about per-module 
converter registries, to avoid conflicts when working with multiple 
extension modules that may provide equivalent converters, where it is 
important to be able to pick explicitly which one is going to be used.

Thanks,
         Stefan


-- 

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