- Boost-users - lists.boost.org

FOREACH with only const_iterators?
by Dave Steffen 06 May '05

06 May '05

Given that this is the user list and not the development list, it might be inappropriate to ask about the FOREACH library, since it hasn't gone into an official release yet. Feel free to point me to the development list. My question is fairly simple: I have a container that only provides const_iterators; it's effectively "read-only" except to a small, select group of classes. Is there a way to tell the BOOST_FOREACH macro to use const_iterator instead of iterator? (Not a huge thing - I can add iterators to the class, or I can teach FOREACH how to iterate over it as described in the docs. I'm just wondering if I'm missing something...) Thanks folks!! ---------------------------------------------------------------------- Dave Steffen, Ph.D. "The only justification for our concepts and Software Engineer IV systems of concepts is that they serve to Numerica Corporation represent the complex of our experiences; ph (970) 419-8343 x27 beyond this they have no legitimacy." fax (970) 223-6797 -- Albert Einstein dgsteffen(a)numerica.us

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[MPL] How to Derive from inherit_linearly generated class?
by Rick Sloan 06 May '05

06 May '05

Hello all, Given a mpl::list typedef mpl::list<structA, structB, structC> typeList; and a wrapper struct template <class T> struct wrap { virtual void someFunction(T&) = 0; virtual ~wrap } You can generate a class by mpl::inherit_linearly<typeList, mpl::inherit<wrap<_2>,_1> >:;type generated; This is pretty much straight from "C++ Template Metaprogramming" pg. 193-194. My question is how do you generate the derived concrete class? I can override any particular function by struct Child : public generated { virtual void someFunction(structA&); } but I can't seem to generate an entire class. I apologize if this is a newbie question, but alas I am a newbie to template metaprogramming. Regards, Rick Sloan

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sorted vectors as associative container?
by Dave Steffen 06 May '05

06 May '05

Hi Folks, Forgive me if this is a stupid question: I'm looking around for an associative-container-implemented-as-a-sorted-vector sort of thing, a la Scott Meyer's "Effective STL" item 23. I could swear Boost had such a thing, maybe called "vec_multiset" or something, a while back. Is there such a thing about? (I've looked at the 'multi-index' containers; they may be what I'm after, but they seem very complicated. My needs are _extremely_ simple...) Thanks! ---------------------------------------------------------------------- Dave Steffen, Ph.D. "The only justification for our concepts and Software Engineer IV systems of concepts is that they serve to Numerica Corporation represent the complex of our experiences; ph (970) 419-8343 x27 beyond this they have no legitimacy." fax (970) 223-6797 -- Albert Einstein dgsteffen(a)numerica.us ___________________ Numerica Disclaimer: This message and any attachments are intended only for the individual or entity to which the message is addressed. It is proprietary and may contain privileged information. If you are neither the intended recipient nor the agent responsible for delivering the message to the intended recipient, you are hereby notified that any review, retransmission, dissemination, or taking of any action in reliance upon, the information in this communication is strictly prohibited, and may be unlawful. If you feel you have received this communication in error, please notify us immediately by returning this Email to the sender and deleting it from your computer.

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The Boost Community
by Fernando Cacciola 05 May '05

05 May '05

Hello people, In 1998, Bemans Dawes wrote the "Proposal for a C++ Library Repository Web Site" (you can find the paper in (www.boost.org/more/index.htm) which lunched the Boost we all know and love today. The focus of the site was and is the production of high-quality peer-reviewed C++ libraries. Over the years, Boost grew as a community of experienced C++ developers with the will and means to share their expertise and work contributing to the highly respected Boost Libraries. Today, Boost is a somewhat recongisable part of the C++ programming community at large. Today, the way I see it, Boost as a community encompases only the boost developers, which are just a fraction of the larger C++ crowd. There are certainly Boost users, but I don't think we can say both developers and users form a community. I think is worth and in-the-spirit to reach out for ALL C++ programmers of ALL LEVELS around an "extended" Boost Community whose main sharing point is not just the submission of high-quality libraries but also the efficient and effective use of the language. A Boost Community site would focus not directly in the Libraries produced by Boost but on C++ itself as the great language we all love and on fostering proper use of it (which includes mixing it with other languages when appropiate). It would be volunteer-driven, just like the Boost libraries are, so the site would be moderated but open for external edition (I think a wiki would work). I envision it having home page links to the fundamental resources for C++ programmers (CUJ,ACCU, "the" books, etc), blogs from developers and users (related to state of the art C++ and/or the boost libraties), important C++ related news (not just boost-library related news), reviews, etc... essentially, everything the will of volunteers can bring on to the community. The motto being "fostering proper use of C++". A minimum of moderation would be required but I assume not much. I know there are other programmer communities around (even C++ focused). The reason I propose this here (around Boost) is becasue I think that a community centered around the Boost Libraries but reaching out could stand out for its quality in the same way the Boost Libraries do. I also know that a newsgroup or mailing list is a form of community, and we have c.l.cpp.m and c.s.cpp. But they lack the verstile structure and dynamism of the today's virtual communities. Also, somehow I believe that centering a community around the Boost Libraries would spread their quality into the rest of the site; to some degree at least. I welcome comments, ctricticism and I call interested people to put forward concrete ideas. Best Fernando Cacciola SciSoft

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RE: [Boost-users] Re: The Boost Community
by Brian Braatz 05 May '05

05 May '05

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of Shishir Ramam > > > > [Brian Braatz Writes:] > > This is a good idea. My simple suggestion is to do this only use > > tinyurl. > > Why not use redirect from www.boost.org/wiki to the one above? > > If the description below is accurate, it seems very simple to do - > http://www.sbrady.com/hotsource/html/redirect.html > > -shishir [Brian Braatz Writes:] Good point, a boost.org redirection is much better

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RE: [Boost-users] Re: The Boost Community
by Brian Braatz 05 May '05

05 May '05

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of Vladimir Krasovsky > Sent: Thursday, May 05, 2005 1:13 AM > To: David Abrahams > Subject: Re: [Boost-users] Re: The Boost Community > > Hello David, > > Thursday, May 5, 2005, 12:17:14 AM, you wrote: > > > I actually love that. > > > www.gotboost.org > > By the way this domain is already used by someone. Can it be a > problem? > [Brian Braatz Writes:] No problem, we just organize an event where everyone on the list shows up at this guy's house at three in the morning politely asking for the domain name. ;)

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RE: [Boost-users] Re: The Boost Community
by Brian Braatz 05 May '05

05 May '05

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of David Abrahams > Sent: Wednesday, May 04, 2005 7:14 PM > To: boost-users(a)lists.boost.org > Subject: [Boost-users] Re: The Boost Community > > "Brian Braatz" <brianb(a)rmtg.com> writes: > > > > > My suggestion- is add to the Wiki site- something that lets a > > person browse the MAILING LIST. > [David Abrahams Writes:] > That's easily done; we can just link to the mailing list archives. We > have many choices there, actually. Just look at > http://www.boost.org/more/mailing_lists.htm and search for "archives." > > > If you can get the interface to the list working as good or better > > than the email version, then more people will start to use the web > > tool, by using the web tool, they will see the Wiki on the way > > in. In this way, the Wiki is put closer to their paradigm. > [David Abrahams Writes:] > Hmm, I'm not sure we can convince everyone to look at the Wiki before > going to the archive pages. > [Brian Braatz Writes:] Yes, it was a weak idea. But generally, the more we can connect the wiki to the mailing list the better. This basic idea hinges upon somehow providing a "really cool and compelling" way to dig around in the archives other than just searching for keywords. When I click on news://news.gmane.org/gmane.comp.lib.boost.user It opens up Outlook Express and gives me a pretty good view of the list. (much better than the Outlook folder I use now for the list) We should be able to find a WEB TOOL that gives the same view. The idea is if you make that web tool a first class citizen and let me hit the page for digging around in the subjects of the list, and additionally "advertise" the wiki in the header of said tool's page, then you have connected the paradigms. :)

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RE: [Boost-users] Re: The Boost Community
by Brian Braatz 05 May '05

05 May '05

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of David Abrahams > Sent: Wednesday, May 04, 2005 1:15 PM > To: boost-users(a)lists.boost.org > Subject: [Boost-users] Re: The Boost Community > > "JOAQUIN LOPEZ MU?Z" <joaquin(a)tid.es> writes: > > 2. Hosting. Dave Abrahams volunteered to host the site. > > Is he still holding his offer? > > I am. It might require getting new hosting resources soon, but at > least initially I'm sure boost-consulting.com can handle the load. [Brian Braatz Writes:] Suggestion: Setup a PayPal link to support the site. If you do, I will be one of the first to donate $$$$.

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Serialization, shared_ptr and namespaces
by Jan Eickmann 05 May '05

05 May '05

Hi, I'm trying to serialize a list of shared_ptr's to objects. Here's a summary of the code I have: namespace MyNamespace { class B { //implementation plus standard serialization function }; class A { private: list< shared_ptr<B> > myBs; public: template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_NVP(myBs); } }; } If I just try to serialize it, I get an unregistered_class exception. So I think I have to use BOOST_SHARED_POINTER_EXPORT(_GUID) to register the shared_ptr. When I include this inside the namespace (please note that the error messages are from my real code, so they have slightly other names: BOOST_SHARED_POINTER_EXPORT(B) I get this: f:\xenocide\xenocide\src\common\simulation\simulation.h(108) : error C2059: syntax error : 'string' f:\xenocide\xenocide\src\common\simulation\simulation.h(108) : error C2146: syntax error : missing ';' before identifier 'BOOST_CLASS_EXPORT_GUID' f:\xenocide\xenocide\src\common\simulation\simulation.h(108) : error C2059: syntax error : 'string' f:\xenocide\xenocide\src\common\simulation\simulation.h(109) : error C2143: syntax error : missing ';' before '}' When I put it outside the namespace I have to use a fully qualified name including the namespace for class B, so it becomes BOOST_SHARED_POINTER_EXPORT(MyNamespace::B) Then I get (not Xenocide is here what MyNamespace is in my example): f:\xenocide\xenocide\src\common\simulation\simulation.h(115) : error C2653: '__shared_ptr_Xenocide' : is not a class or namespace name f:\xenocide\xenocide\src\common\simulation\simulation.h(115) : error C2653: '__shared_ptr_Xenocide' : is not a class or namespace name I also tried various combinations with BOOST_SHARED_POINTER_EXPORT_GUID but it didn't help. Can someone explain to me how I have to declare shared_ptr's in order for them to work with boost::serialization? I was unable to find some more indepth documentation. Thanks, Jan Eickmann

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Re: [Boost-users] Compatibility between shared_ptr and Rational RoseRT
by Ross Manges 05 May '05

05 May '05

> When running the executable under Rational Purify, it reports many FIM > errors (Freeing Invalid Memory), and all of these are again due to the > deletion of objects that were owned by a shared_ptr. Is your program (the code that uses shared_ptrs) running in multiple threads? I am seeing problems with my multithreaded code where the use_count in the shared_ptrs is not accurate and causing all sorts of problems. I'm even seeing core dump backtraces showing problems in the scoped_lock where the shared_ptr use_count is getting updated. It appears that there are a lot of restrictions on how shared_ptrs can be used in a multithreaded program, and I may be breaking some of those restrictions as it is easy to do so. In any case, let me know if you find a solution to your FIM errors. I have a feeling I'm seeing symptoms of the same problem. Thanks.

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