March 2012 - Boost - lists.preview.boost.org

Boost 1.49 BOOST_PP_ITERATION_FLAGS(): causes build failures; would like a boost maintainer comment
by Steve M. Robbins 13 Mar '12

13 Mar '12

Would really appreciate if ticket 6631 is a Boost bug that I can patch for Debian, or whether it is just API breakage that boost-using packages (like luabind) must adapt to. Thanks, -Steve #6631: BOOST_PP_ITERATION_FLAGS(): error: missing binary operator before token "(" --------------------------------+------------------------------------------- Reporter: peter@??? | Owner: no-maintainer Type: Bugs | Status: new Milestone: To Be Determined | Component: preprocessor Version: Boost 1.49.0 | Severity: Regression Resolution: | Keywords: BOOST_PP_ITERATION_FLAGS --------------------------------+------------------------------------------- Changes (by Steve Robbins <smr@???>): * cc: smr@??? (added) Comment: I am currently investigating building all Debian packages with Boost 1.49 and "luabind" fails to build with very similar symptoms. Can the boost maintainer comment whether this is a bug in boost or a simple API break. Thanks, -Steve

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Hi-Introduction
by Rhythm Gupta 13 Mar '12

13 Mar '12

Hi, I'm Rhythm Gupta. I am a first year student of Computer Science in IIT Delhi, India. I love coding and i have strong background in Maths and Science. Hence, BoostC++ looks like the perfect organisation for me. :-) Would like to apply for BoostC++ in GSoC. Could you help me get started with BoostC++?

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Boost B-Tree Library Status
by Joel 12 Mar '12

12 Mar '12

Beman et al, Is the Boost B-tree Library still on track to be proposed? The reception at BoostCON 2011 was quite warm, IIRC. http://github.com/boostcon/2011_presentations/raw/master/tue/proposed_b_tre… Activity on github seems to be dried up. https://github.com/Beman/Boost-Btree Also, how well do you think it would work with large keys and small payloads (512 byte keys, a few integers for payload). Thanks! Joel

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[GIL] gil/metafunctions.hpp broken in 1.49?
by Andrew Hundt 12 Mar '12

12 Mar '12

I may be mistaken, but it looks like boost::mpl::vector_c may have been moved from <boost/mpl/vector.hpp> to <boost/mpl/vector_c.hpp> and it appears <boost/gil/metafunctions.hpp> has not been updated to reflect this change. Cheers! Andrew Hundt

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[fusion] Fusion using varidiac templates
by paul Fultz 12 Mar '12

12 Mar '12

hi, I remember seeing that there was an initial port of fusion to use variadiac templates a while back. Is that code available somewhere? If so, where could a find that? Thanks, Paul

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Using an element of a class A in a constructor of a class B (reflection with boost::python)
by christophe jean-joseph 12 Mar '12

12 Mar '12

Hello The situation is as follow. I have a C++ code that I haven't written and that I barely can modified. I am supposed to reflect this code in Python with boost. In the code, I have something looking like this: Class A_Base { A_Base(){}; ~A_Base(){}; Whatever virtual and pure virtual functions; } Class A_Derived{ A_Derived(Type1 arg1,...){whatever instructions;} ~A_Derived(){}; Whatever functions; } Class B { B(A_Base& aBase, double& x){}; ~B(){}; Whatever functions; } In the C++ main, at some point aDerived A_Derived is set, and then B(aDerived, x). I need to reflect that under python. Until now, I have been able, with a simple example, to reflect a function f, which is not a ctor, from a class B using A_Base& as argument type, but I can't figure out how to deal with it for a constructor. Based on: http://wiki.python.org/moin/boost.python/ExportingClasses I am declaring f under both its class B and A_Base as follow: .def("f", &B::f) But when I try this for a constructor as f, it refuse to compile. Anyone got a clue? Thank you very much in advance for any further help.

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Keynotes for C++ Now!
by Jon Kalb 12 Mar '12

12 Mar '12

C++ Now! (formerly BoostCon) is pleased to announce its lineup of keynote speakers for the 2012 conference: Howard Hinnant, Sean Parent, and Daveed Vandevoorde. Howard Hinnant is the principal author of libc++, the standard C++ library implementation used by the Clang compiler. During the development of C++11, Howard served as chairman of the C++ Standards Committee¹s Library Working Group, and is largely responsible for the design of what Scott Meyers has called the language¹s ³flagship new feature:² rvalue references. His keynote will demonstrate how rvalue references are used in move semantics and perfect forwarding. Sean Parent is a principal scientist and software architect for Adobe¹s mobile digital imaging group and formerly managed Adobe¹s Software Technology Lab. He was also the keynote speaker for the very first BoostCon, where he gave one of the most inspiring and memorable talks we¹ve ever had. We¹re very pleased to welcome him back for an encore. He will be speaking on what¹s next for C++ programmers: how do we write beautiful code that truly exploits today¹s hardware and infrastructure? Daveed Vandevoorde is a compiler developer with Edison Design Group, the author (with Nicolai Josuttis) of ³C++ Templates: The Complete Guide,² a co-founder of comp.lang.c++.moderated, and one of the few C++ Committee Members who is equally comfortable working on library design, language evolution, or the arcana of core language issues. Daveed is currently a leader in the effort to add true modules to the C++ language. He¹ll be talking about the design of the C++ modules feature and what it would mean for the future of the language. ³We are thrilled to have such a powerhouse lineup in the first year of the new language standard,² said Dave Abrahams the conference founder and co-chair. ³C++Now! 2012 is truly shaping up to be a feast for the C++ enthusiast.² C++ Now! 2012 will be held May 13-18 in Aspen Colorado. Registration is now open at http://cppnow.org/registration/. Keynote details at http://cppnow.org/overview/. Jon

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boost::algorithm::trim_copy() behaves like "strdup" in normal C, does it allocate a new string ?
by g.fanini＠gmail.com 11 Mar '12

11 Mar '12

Could I ask for a clarification whether boost::algorithm::trim_copy() behaves like "strdup" in normal C, i.e. does it allocate a new string ? or does it modify the passed string without allocating a new string ? It is not entirely clear from the documentation : http://www.boost.org/doc/libs/1_34_0/doc/html/boost/algorithm/trim_copy.html Because the argument passed has the modifier "const" I am led to believe it would leave the passed string unchanged, and return a newly allocated string. Possibly would you consider kindly updating the documentation reflecting the returned string is newly allocated.I am asking this becauseI am trying to work with preexisting boost code which uses boost::algorithm::trim_copy() profusely and I have severe leakage problems.Thank you for any information.

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[bgl] Update on maximum adjacency search
by Fernando Vilas 11 Mar '12

11 Mar '12

Hi, Since the last round of feedback, I think the implementation is at least closer to being releasable. This is not quite a re-send because I attached the wrong patch last time, but I also forgot the subject tags to get the attention of the BGL folks. Changes: - All parameters other than the graph itself are available as named parameters - Visitor is not pass-by-value like other search algorithms - Documentation created Still potential todo: - Update documentation with graphical walkthrough on a small graph - Find a way to make the priority queue work without unwrap_ref() - Do not depend on one_bit_color_map internals in min_cut_mas_visitor - Other suggestions from Boost community -- Thanks, Fernando Vilas fvilas(a)iname.com

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Re: [boost] Boost.ntree_container (bi_tree, quad_tree, oct_tree, etc ptr containers) Is there any interest in this?
by Dan Walters 11 Mar '12

11 Mar '12

Hi all, This is my current implementation of an oct tree that I am using on a project I am working on. It is a templated oct tree which serves as a pointer container. There is usage shown in the main() function at the bottom of the sample. http://codepad.org/yIAblSDN Please bear in mind it is not fully optimized or std compliant, just put together for a project but shows the intended basic functionality and method. Compatibility with boost geometry is a great suggestion. Again, I am mindful of defining the boundaries of this library, but if it makes sense then template specialization or utility code could be provided to use the libraries together easily and elegantly. k-d trees are very interesting, and if discussion found these potentially useful enough, they would certainly belong in the same library. I think, in any context, this should be thought of as a container library above all else and would be potentially useful not just in game or geometry programming, but open to use where ever useful, including as a memory efficient pointer container for sparsely populated multidimensional arrays. Best wishes, Dan On 10 March 2012 20:04, Daniel F. Savarese <dfs(a)savarese.org> wrote: > > In message <848178090.20120310163009(a)gmail.com>, pavel writes: > >by the way i have a ready implementation of kd trees (if anyone is > >interested): > > > > > http://programmizm.sourceforge.net/blog/2011/a-practical-implementation-of-… > >trees > > That's not exactly a generic implementation, nor one that is STL-friendly > (e.g., no iterators). For a more generic implementation that aims for STL > interoperability where possible, see the header-only libssrckdtree library: > http://www.savarese.com/software/libssrckdtree/ > > But this is off-topic for the thread, which--as I understand it--is > concerned > with fixed-size multidimensional spatial pointer containers oriented toward > 3D applications, not variable-sized multidimensional spatial value > containers > applicable to arbitrary domains. > > daniel > > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost >

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