David Abrahams wrote:
The best thing you could do, IMO, is write a recommendation that works on conforming compilers, e.g.
Overload serialize in the namespace of your class.
Oh, that's news to me. I thought that would work only in compilers that implemented ADL. I understood from previous postings that this would entail building a set a macros which addressed the varying aspect of conformity. In 1.32 I had #if ... in order to place stl serializations in either the stl namespace or the boost::serialization namespace depending on whether the compiler supported ADL and two-phase lookup or neither of these things. That was the only way I could get everything to compile on all platforms. Then generated the requirement to address the issue in the documentation with a table on what the user should use. That's what I call ugly. FWIW - I'm not sure if the example you site would ever come up in practice - it certainly hasn't yet. If I understand this correctly, the problem would occur if someone writes somethng like: my_class.hpp class my_class ... template<class Archive, my_class> void serialize(Archive &ar, my_class & t, cont unsigned int version); // declaration only my_app.cpp main(... { my_class mc; ... ar & mc; } template<class Archive, my_class> void serialize(Archive &ar, my_class & t, cont unsigned int version); // definition only I'm not absolutly sure that this is the only scenario which would create problem and that's why I wanted more time to consider it. If this is the only way the two-phase problem could manifest itself, I would guess that in practice it would never be an issue. I don't see users doing this. This was what I was getting at when I asked why the problem hasn't appeared upto now. Of course I don't really know whether this is because so many compilers fail to implement two-phase lookup.
b) I'm going to remove the class declaration and function implementation from the Archive Concept part of the document.
Are you planning to replace it with anything? It would be pretty silly to have a section called Archive Concept with no concept description.
I meant to leave in the text below the "class" schema. Before I started I reviewed again the SGI documents and concluded that that text could be fit into the SGI form for concepts. I'm using http://www.sgi.com/tech/stl/Container.html as a "typical example". This isn't hard - its basically a question of reformatting. I hope that will be satisfactory.
The above I will check into RC_1_33_0
Other issues that I intend to defer for the next version
d) investicate the two-phase lookup issue. There is no way any such change could be made for RC_1_33_0 and the next boost release won't be for another 10? months, so I feel that I can take some time with this.
That seems extreme to me. Surely for RC_1_33_0 a documentation fix that provides instructions that are both correct for conforming compilers and consistent with the current library implementation is possible? Not much more than a small tweak in emphasis would be required.
see above. Robert Ramey