Re: [boost] [type_erasure] ODR violation promotion

Subject: Re: [boost] [type_erasure] ODR violation promotion
From: Gordon Woodhull (gordon_at_[hidden])
Date: 2011-09-09 15:46:02

On Sep 9, 2011, at 3:26 PM, Vicente J. Botet Escriba wrote:

> Le 09/09/11 20:44, Steven Watanabe a écrit :
>> 
>>> Before the Boost.Conversion review someone signaled that the
>>> Boost.Conversion review was promoting ODR violations as two libraries
>>> could specialize a conversion for types S and T and make them
>>> incompatible for an end user as the ODR is violated.
>>> 
>>> I think that your library suffer from the same issue, when two libraries
>>> need to specialize a concept provided by the library for a 3rd part
>>> concrete class using the proposed concept map mechanism. Do you agree?
>>> If not, how do  the library avoids this kind of issue?
>>> 
>> I have no intention of trying to deal with it.
>> As far as I'm concerned it's the responsibility
>> of whoever defines the specializations.  I'm
>> not going to worry about it at all until I
>> hear reports of it causing real problems, as
>> opposed to being a purely theoretical concern.
>> 
>> 
> IIUC you response, you agree that your library has the same problem.

Or, it is not a real problem.

Or, as Roman Perepelitsa suggested, it is a more serious problem if you are defining customizations on two types, because then it is unclear which library has responsibility for defining the customizations.

Cheers,
Gordon