August 2014 - Boost-users - lists.preview.boost.org

Re: [Boost-users] Cannot use Boost.Croutines with range based for
by Mueller-Roemer, Johannes Sebastian 27 Aug '14

27 Aug '14

Adding the following namespace boost { namespace coroutines { using boost::begin; using boost::end; } } solves the problem, however this would seem to indicate that the provided begin and end are in the wrong namespace and therefore do not take part in ADL. Should I report this as a bug? Doesn't seem to be intended. -- Johannes S. Mueller-Roemer, MSc Wiss. Mitarbeiter - Interactive Engineering Technologies (IET) Fraunhofer-Institut für Graphische Datenverarbeitung IGD Fraunhoferstr. 5 | 64283 Darmstadt | Germany Tel +49 6151 155-606 | Fax +49 6151 155-139 johannes.mueller-roemer(a)igd.fraunhofer.de | www.igd.fraunhofer.de From: Mueller-Roemer, Johannes Sebastian Sent: Wednesday, August 27, 2014 12:57 To: 'boost-users(a)lists.boost.org' Subject: Cannot use Boost.Croutines with range based for Hi, I am (again) having issues with the Boost.Coroutines library. Aside from yet another new API, the coroutines no longer work with range based for. Even though the examples include range based for! With the following code (taken directly from the documentation and added the includes and main): #include <boost/coroutine/asymmetric_coroutine.hpp> #include <iostream> int main() { boost::coroutines::asymmetric_coroutine<int>::pull_type source( [&](boost::coroutines::asymmetric_coroutine<int>::push_type& sink){ int first=1, second=1; sink(first); sink(second); for(int i=0;i<8;++i){ int third=first+second; first=second; second=third; sink(third); } } ); for(auto i : source) std::cout << i << " "; } I get this error: D:\projects\combinators\coro_test.cpp: In function 'int main()': D:\projects\combinators\coro_test.cpp:20:15: error: 'begin' was not declared in this scope for(auto i : source) ^ D:\projects\combinators\coro_test.cpp:20:15: note: suggested alternatives: In file included from D:\projects\combinators\coro_test.cpp:1:0: D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/coroutine/asymmetric_coroutine.hpp:2255:1: note: 'std::begin' begin( boost::coroutines::push_coroutine< R > & c) ^ In file included from D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/range/functions.hpp:18:0, from D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/range.hpp:18, from D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/coroutine/asymmetric_coroutine.hpp:17, from D:\projects\combinators\coro_test.cpp:1: D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/range/begin.hpp:106:61: note: 'boost::range_adl_barrier::begin' inline BOOST_DEDUCED_TYPENAME range_iterator<const T>::type begin( const T& r ) ^ D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/range/begin.hpp:106:61: note: 'boost::range_adl_barrier::begin' D:\projects\combinators\coro_test.cpp:20:15: error: 'end' was not declared in this scope for(auto i : source) ^ D:\projects\combinators\coro_test.cpp:20:15: note: suggested alternatives: In file included from D:\projects\combinators\coro_test.cpp:1:0: D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/coroutine/asymmetric_coroutine.hpp:2260:1: note: 'std::end' end( boost::coroutines::push_coroutine< R > & c) ^ In file included from D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/range/functions.hpp:19:0, from D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/range.hpp:18, from D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/coroutine/asymmetric_coroutine.hpp:17, from D:\projects\combinators\coro_test.cpp:1: D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/range/end.hpp:100:61: note: 'boost::range_adl_barrier::end' inline BOOST_DEDUCED_TYPENAME range_iterator<const T>::type end( const T& r ) ^ D:/libs/mingw-amd64/boost_1_56_0/include/boost-1_56/boost/range/end.hpp:100:61: note: 'boost::range_adl_barrier::end' mingw32-make[2]: *** [CMakeFiles/coro-test.dir/coro_test.cpp.obj] Error 1 mingw32-make[1]: *** [CMakeFiles/coro-test.dir/all] Error 2 mingw32-make: *** [all] Error 2 For completeness sake: I am using MinGW-w64 with GCC 4.9.1 and the -std=c++11 flag Regards, Johannes S. Mueller-Roemer -- Johannes S. Mueller-Roemer, MSc Wiss. Mitarbeiter - Interactive Engineering Technologies (IET) Fraunhofer-Institut für Graphische Datenverarbeitung IGD Fraunhoferstr. 5 | 64283 Darmstadt | Germany Tel +49 6151 155-606 | Fax +49 6151 155-139 johannes.mueller-roemer(a)igd.fraunhofer.de<mailto:johannes.mueller-roemer@igd.fraunhofer.de> | www.igd.fraunhofer.de<http://www.igd.fraunhofer.de>

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[Smart Pointer] Reference counting when you don't want to manage memory [Honeywell Internal]
by Hickman, Steve (AdvTech) 26 Aug '14

26 Aug '14

Classification: Honeywell Internal Smart pointers (as in http://www.boost.org/doc/libs/1_56_0/libs/smart_ptr/smart_ptr.htm ) assume that the action you want to perform when the count goes to zero is to free the memory pointed to. That isn't the only use for reference counting. Why doesn't the Smart Pointer library decouple the reference counting from the action to be taken and provide a generic reference counting mechanism that will call an arbitrary function when the count goes to zero? The default can be "delete" to provide the expected memory management capability but it would provide a robust mechanism for those who need other capabilities. Reviewing the <boost/shared_ptr.hpp> code, it appears this decoupling already exists - through the use of boost::checked_delete and boost::checked_deleter (<boost/checked_delete.hpp>). It just doesn't appear to be documented. Why not document this so others know how to use it? Steve Hickman System Architect, Flight Deck of the Future 480-236-8367 ============================================================================================================================================================================================================ This message classified as Honeywell Internal by Hickman, Steve (AdvTech) on Tuesday, August 26, 2014 at 12:35:32 PM. The above classification labels are in accordance with the Honeywell Corporate Classification Policy. The information contained in this electronic message is confidential and intended only for the use of the individual/entity named above, and the information may be privileged. If you, the reader of this message, are not the intended recipient or an employee or agent responsible to deliver this message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please immediately notify the sender and delete the original message. ============================================================================================================================================================================================================

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Multi-Index: custom iterator
by Sensei 26 Aug '14

26 Aug '14

Dear all, I'm not yet satisfied with my MultiIndex games, so now I am trying to do something that is purely cosmetic. However, I have *no idea* how I can do this. How can I build a custom iterator on a MultiIndex? The objective is simple. As you may recall, I am building a MultiIndex with 128 bits, indexing them by MSB, LSB, and HSB (in the middle). It works like a charm. Now I'd like to write something like this (or similar): auto it = storage.myfind<byMSB>(MSB(value128bits)); for (; i != it.end(); i++) In essence, I'd like to hide the get<> and everything I am using right now (as shown below). So I need an iterator for this data structure: typedef __uint128_t Storage; // Indexing placeholders struct byMSB { }; struct byHSB { }; struct byLSB { }; // Storage type with indexing typedef boost::multi_index::multi_index_container< Storage, boost::multi_index::indexed_by< // Hashed by subject/predicate/object boost::multi_index::hashed_non_unique<boost::multi_index::tag<byMSB>, boost::multi_index::global_fun<Storage, soSub, &Data::msb>>, // 0 boost::multi_index::hashed_non_unique<boost::multi_index::tag<byHSB>, boost::multi_index::global_fun<Storage, soPre, &Data::hsb>>, // 1 boost::multi_index::hashed_non_unique<boost::multi_index::tag<byLSB>, boost::multi_index::global_fun<Storage, soObj, &Data::lsb>> // 2 > > DataStorage; DataStorage storage_; With your suggestions I've achieved to find all items by MSB, but sincerely, now I don't know how to write a custom iterator for this type. The code for finding elements is this: //typedef typename DataStorage::template nth_index<0>::type byHashedIndex; //typedef typename DataStorage::template index<byMSB>::type byHashedIndex; //byHashedIndex &p = storage_.template get<byMSB>(); auto &p = storage_.template get<byMSB>(); auto q = p.equal_range(subject(v)); while (q.first != q.second) { std::cout << " EQID " << *(q.first) << " | " << msb(*(q.first)) << " | " << hsb(*(q.first)) << " | " << lsb(*(q.first)) << std::endl; l.push_back(*(q.first)); q.first++; } Note: I *have* written iterators, but they were much easier (for instance char*). This is far too complex for making my way on my own! From the code above, I guess I have begin() and end() point to an equal_range output .first and .second. But what will the "pointer" I need in the iterator will be? Of course, my first attempt is a complete failure: // Iterator template <class T> class iterator : public std::iterator<std::input_iterator_tag, Storage> { typedef typename DataStorage::template index<T>::type byHashedIndex; byHashedIndex &p; // Default constructor iterator() : p(storage_.get<T>()) { }; // Copy constructor iterator(const iterator& i) : p(i.p) { }; // Pre-increment ++it iterator& operator++() { ++p; return *this; }; // Post-increment it++ iterator operator++(int) {iterator tmp(*this); operator++(); return tmp; }; // Equality bool operator==(const iterator& rhs) { return p == rhs.p; }; // Non-equality bool operator!=(const iterator& rhs) { return p != rhs.p; }; // Access Storage& operator*() { return *p; }; // Difference iterator operator-(int i) { return iterator(p - i); }; // Addition iterator operator+(int i) { return iterator(p + i); }; }; Can you point me in the right direction? Thanks!

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"newbie" Build Boost Matrix
by Ismael Fadiga 25 Aug '14

25 Aug '14

hi all After executing the below sql query in c++, the printed results are: WITH rnum AS (SELECT s.ISN, s.Date, ClosedPrice, row_number() OVER (partition BY s.ISN ORDER BY s.ISN, s.Date DESC) AS rownumber FROM SecurityData s INNER JOIN PortfolioHoldings p ON s.ISN = p.ISN WHERE p.Pfid = 1876) SELECT DISTINCT ISN, Date, ClosedPrice FROM rnum WHERE rownumber <= 250)) //ID Date Price US345 2014-08-17 342 US345 2014-08-16 310 ... FR123 2014-08-17 18.20 FR123 2014-08-16 15 Does anyone know how to build a price matrix for the IDs like:? |342 18.20| MAT=|310 15 | |... ... | Your feedback would be very appreciated Cheers

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[ConceptCheck] Same type concept
by Robert Jones 25 Aug '14

25 Aug '14

I'd like a concept check to check for two types being the same type. I can see how to write such a concept, but this is such an obvious requirement that either there should be one already, or there's some blindingly obvious reason why you never need one, a reason that escapes me. A little guidance would be appreciated. Thanks, Rob.

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Re: [Boost-users] [Chrono] The default BOOST_CHRONO_VERSION is still 1
by DonM 24 Aug '14

24 Aug '14

-------- Original Message -------- Subject: Re: [Boost-users] [Chrono] The default BOOST_CHRONO_VERSION is still 1 From: "Vicente J. Botet Escriba" <vicente.botet(a)wanadoo.fr> Date: 8/23/2014 6:28 AM To: boost-users(a)lists.boost.org > > Le 23/08/14 01:41, DonM a écrit : >> The docs (boost_1_56_0/doc/html/chrono/reference.html) say: >> >> "The default value for BOOST_CHRONO_VERSION will be changed to 2 since Boost 1.55. " >> >> However, it still has the value 1 in both 1.55 and 1.56. >> >> Not a big deal, I just noticed and figured I'd mention it. >> > Hi, > > I must remove this comment as as there is a incompatibility this will break user code. I planned to do a smooth trarnsition, but there were some complains. > > Thanks for pointing this issue, > Vicente Are you saying that you never intend to change the default value? That would be a mistake, in my opinion. Version 2 is much better -- the I/O stuff works. If users need backwards compatibility, they can define version 1, but encourage people to use version 2. Just my $0.02. Don

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[move] Movable but not copyable bug?
by Mostafa 24 Aug '14

24 Aug '14

Given the following code, if (1) is uncommented then it fails to compile under C++03 mode yet works in C++11 mode. If commented out, then it compiles successfully under both modes. (g++ 4.8.2 is being used) Is this behavior expected or a bug? #include <boost/move/core.hpp> #include <boost/move/utility.hpp> struct Foo { Foo(int x, int y) {} Foo(BOOST_RV_REF(Foo) rhs) {} private: //Purposefully declared and not defined. Foo & operator=(Foo); private: BOOST_MOVABLE_BUT_NOT_COPYABLE(Foo) }; template <typename T> struct Bar { Bar() : f(0, 1) {} // (1) // Bar(Bar const & rhs) // : f(rhs.f) // {} Bar(BOOST_RV_REF(Bar) rhs) : f(::boost::move(rhs.f)) {} private: //Purposefully declared and not defined. Bar & operator=(Bar); private: BOOST_COPYABLE_AND_MOVABLE(Bar) private: T f; }; Foo f1() { // (2) // Foo f(0, 1); // return f; // (3) return Foo(0, 1); } Bar<Foo> f2() { return Bar<Foo>(); } int main() { // Foo f( f1() ); Bar<Foo> b(Bar<Foo>()); return 0; }

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BGL: boost::astar_search_no_init
by Georg Gast 24 Aug '14

24 Aug '14

Hi there! Currently i try to implement an astar search with BGL and boost. My graph is infinite, so i searched for an example of astar_search_no_init and found this: http://lists.boost.org/boost-users/2012/03/73707.php I am on gcc-4.9.0 and boost 1.52.0 on linux. I try to compile the above example and get the following error which i cant decipher ... make gcc -std=c++11 example.cpp -o example example.cpp: In function 'int main(int, char**)': example.cpp:274:140: error: no matching function for call to 'boost::associative_property_map<default_map<std::pair<XY, XY>, unsigned int> >::associative_property_map(default_map<std::pair<XY, XY>, unsigned int>)' . weight_map(boost::associative_property_map<default_map<std::pair<XY,XY>,unsigned> >(default_map<std::pair<XY,XY>,unsigned>(1))) I added the code as an attachement. For me it seems that this line is not ok .... but i currently have no clue how to fix it ... try { astar_search_no_init(g, start, distance_heuristic<XYGraph>(goal) , visitor(astar_goal_visitor(goal)) . distance_map(d) . predecessor_map(boost::ref(p)) . weight_map(boost::associative_property_map<default_map<std::pair<XY,XY>,unsigned> >(default_map<std::pair<XY,XY>,unsigned>(1)) // < --- line 274 . vertex_index_map(boost::associative_property_map<std::map<XY,unsigned> >(std::map<XY,unsigned>())) . rank_map(boost::associative_property_map<std::map<XY,unsigned> >(std::map<XY,unsigned>())) . color_map(boost::associative_property_map<std::map<XY,boost::default_color_type> >(std::map<XY,boost::default_color_type>())) . distance_compare(std::less<unsigned>()) . distance_combine(std::plus<unsigned>()) ); with clang 3.4 i get this error line. clang --std=c++11 example.cpp -o ex example.cpp:274:26: error: no matching conversion for functional-style cast from 'default_map<std::pair<XY, XY>, unsigned int>' to 'boost::associative_property_map<default_map<std::pair<XY, XY>, unsigned int> >' . weight_map(boost::associative_property_map<default_map<std::pair<XY,XY>,unsigned> >(default_map<std::pair<XY,XY>,unsigned>(1)) So what ant the author of this code do? Allocate a property map of size 1? Currently i dont see the forrest, there are so many trees in my view .... Any help would be appreciated! Thank you! Georg

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[Chrono] The default BOOST_CHRONO_VERSION is still 1
by DonM 23 Aug '14

23 Aug '14

The docs (boost_1_56_0/doc/html/chrono/reference.html) say: "The default value for BOOST_CHRONO_VERSION will be changed to 2 since Boost 1.55. " However, it still has the value 1 in both 1.55 and 1.56. Not a big deal, I just noticed and figured I'd mention it. Don

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Boost.ASIO calling handler guarantees
by Фёдор Трушкин 23 Aug '14

23 Aug '14

Hello, Dear All, I'm playing with Boost.ASIO framework and failed to find a complete answer on the following question. Under which circumstances is it guaranteed that asynchronous operation completion handler is called? Plainly speaking, is this example code correct? void my_handler(const error_code &ec) { if(!ec) { /* process successful operation */ } else { /* process failed operation */ } try { async_write(port, my_handler2) } catch(...) { // processing failure to execute asynchronous operation } } Obviously here I rely heavily upon the above mentioned guarantee. Looking at least at async_write() implementation, it cannot be relied upon: - async_write executes a chain of boost::asio::detail::write_op() operations: - if asio_handler_allocate() may throw then - write_op::stream_.async_write_some() may throw then - write_op.handler_() might never be called So, either we should never rely on this assumption, or there's a bug in async_write(). Not relying on this assumption what is the reliable way of building applications with Boost.Asio? Sincerely yours, Fedor Trushkin

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Installing 1.56 on Fedora 20
by Robert Jones 22 Aug '14

22 Aug '14

It's been a while since I've installed Boost. Running this command on a completely vanilla Fedora 20 b2 --prefix=~/local/boost-1.56.0 --layout=tagged link=shared threading=multi,single install Finally says... ...failed updating 58 targets... ...skipped 12 targets... ...updated 12214 targets... Is this normal? Thx, Rob.

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exercism.io -- crowd-sourced mentorship C++ track online
by legalize+jeeves＠mail.xmission.com 22 Aug '14

22 Aug '14

[Please do not mail me a copy of your followup] Hi Boost-ers, Katrina Owens has created <http://exercism.io>, a web site designed to help programmers get better at their craft through crowd-sourced mentorship. The whole thing is free and open source and all you need to participate is a github account. I have contributed a basic set of completed exercises to enable the C++ language track. I would love for people from the boost community to participate in the C++ track. I had fun doing the initial set of exercises. Most of them could be completed in under 20 minutes, although the intention is that they increase in difficulty as you progress through them. For each exercise you are presented with the problem statement and a set of Boost.Test unit tests. The goal is to get a program that achieves the function and is expressive and readable. First you get all the tests passing in order to achieve the desired function, but then revise the code to get it to be more expressive and idiomatic in the language. It's that last part where the crowd-sourced mentorship comes into play -- once you've submitted your solution for a problem to the website, you'll be able to view the solutions other people have submitted for the same exercise in the same language. You can mentor them in how to write more expressive, idiomatic C++11 code. Who knows, maybe you'll also improve your C++11 skills by reading feedback from others on your submissions. Feel free to comment here or file an issue on the exercism.io github repository <http://github.com/exercism/exercism.io> if you think the C++ track needs more or better instructions or helpful links. -- "The Direct3D Graphics Pipeline" free book <http://tinyurl.com/d3d-pipeline> The Computer Graphics Museum <http://computergraphicsmuseum.org> The Terminals Wiki <http://terminals.classiccmp.org> Legalize Adulthood! (my blog) <http://legalizeadulthood.wordpress.com>

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Serializing std::vector<double>**
by salman arshad 22 Aug '14

22 Aug '14

Hello, I want to serialize std::vector<double>**. I tried but may be I did not look into right places but I can serialize a std::vector<double>* without any problem but not a pointer to a pointer to vector. I think I am doing something really stupid here or missing something. Any help is highly appreciated. Regards, Salman Arshad

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[review] Formal review period for VMD library begins today, Aug 21, and ends Sat, Aug 30
by Steven Watanabe 21 Aug '14

21 Aug '14

AMDG The formal review of the VMD library by Edward Diener starts today, Aug 21st and is scheduled to continue until Aug 30th. About VMD =============== The Variadic Macro Data library is a library of variadic macros which enhance the functionality in the Boost preprocessor library ( Boost PP ). The main focus of the library is the parsing/identifying of a subset of C++ preprocessor data types and of all Boost PP data types. This allows enhanced preprocessor metaprogramming based on the type of macro input. The library may also be seen as a repository for future enhancements to the Boost PP library functionality using variadic macros. Where to get it =============== The library is available on github at https://github.com/eldiener/variadic_macro_data Review guidelines ================= Reviews should be submitted to the developer list (boost(a)lists.boost.org) with '[vmd]' in the subject. Or if you don't wish to for some reason, you can send them privately to me. If so, please let me know whether or not you'd like your review to be forwarded to the list. For your review you may wish to consider the following questions: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With what compiler? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? And finally, every review should answer this question: - Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. In Christ, Steven Watanabe

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A library for "string chains"?
by legalize+jeeves＠mail.xmission.com 21 Aug '14

21 Aug '14

[Please do not mail me a copy of your followup] For a motivating example, see this gist: <https://gist.github.com/LegalizeAdulthood/7b67968bd93fbd4f9dbb> It uses boost::mapped_file to map a mail message into memory and then proceeeds to parse it. This is simply an example, but I think this hacked up parser comes fairly close to handling the full RFC2822 message, ignoring MIME extensions. <https://tools.ietf.org/html/rfc2822> I hacked it up from memory of mail message format rules and a single example message, so don't consider it production quality :-). The intention here is to parse a file without copying it's input text into any buffers. Notice that this parser builds structure from a buffer by identifying interesting substrings as (b,e) pointer pairs. A more traditional approach would have involved at least 2 more copies: one that gets the data from the file system into the stream buffer and another one that copies the data from the stream buffer into a std::string. The extra copying can take significant amounts of time when processing thousands of mail messages. Mail messages tend to be short, so mapping them into memory is not such a big deal. Obviously there is a lifetime relationship between the mapped file (the source character buffer) and the associated strings. For my use case, I'm not interested in being able to write to the strings, just read from them. (If you look closely you'll see that I "cheat" and add a few segments into my string that are associated with const char* C-style strings, but they too are read-only.) I'm interested to know if anyone is aware of a "string chain" library that provides a (read-only) API similar to std::string, but is fundamentally just managing (b,e) pointer pairs into some larger buffer. Boost.Test has a funky string class hiding in it called basic_cstring, but it wasn't created for this purpose. -- "The Direct3D Graphics Pipeline" free book <http://tinyurl.com/d3d-pipeline> The Computer Graphics Museum <http://computergraphicsmuseum.org> The Terminals Wiki <http://terminals.classiccmp.org> Legalize Adulthood! (my blog) <http://legalizeadulthood.wordpress.com>

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[Serialization] 1.56.0 - unregistered_class exception while using EXPORTs
by Todd Seiler 20 Aug '14

20 Aug '14

I've been pulling my hair out for a couple of days trying to get this to work. When I serialize something from a base pointer, it throws an "unregistered_class" exception. I know the type of object that's being serialized and that class has "BOOST_CLASS_EXPORT_KEY" in the header and "BOOST_CLASS_EXPORT_IMPLEMENT" in the cpp file with the same name. In the save and load functions I also have: boost::serialization::void_cast_register( static_cast<Derived*>(NULL), static_cast<Base*>(NULL)); The base class is an abstract base class with one pure virtual function method. But here are the differences: 1) I tried using the "ASSUME_ABSTRACT....." macro. That didn't do anything for me. 2) The abstract base class also has a cpp file with some code in it. I'm not sure if that matters or not... Here's the thing. I can get the derived class's "save" method to be called with this code: std::ofstream o(case_path_ + "/" + file_name); if (o.good()) { // MUST HAVE THIS boost::serialization::void_cast_register<Derived, Base>( static_cast<Derived*>(NULL), static_cast<Base*>(NULL)); boost::archive::polymorphic_text_oarchive oa(o); boost::archive::polymorphic_oarchive & oa_interface = oa; oa_interface << base_ptr; } Having the void_cast_register() there sort of defeats the purpose though. I shouldn't need to pre-register them. In all the examples, I see the void_cast_register() inside of the "save" and "load" methods, which is what I have already. All my serialization code resides in cpp files. Also, the serialization code resides in a static lib. But the archive creation and the action to serialize is performed in a dynamic lib. I am also using polymorphic archives everywhere. I've also forced template instantiation of all serialization code and polymorphic archive interface stuff. Any clue?

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[Serialization] 1.56.0 - How to serialize polymorphic base class data without derived data
by Todd Seiler 20 Aug '14

20 Aug '14

Basically, I'm looking to serialize a base class that's polymorphic, from a base class pointer, without it calling the derived class's serialize functions... Here is my setup: class RenderableMesh : public BasicMesh, public DynamicRenderable; Basically, I don't want it to serialize RenderableMesh or DynamicRenderable given a "basicMesh" pointer. The reason is because "DynamicRenderable" derives from a class inside the "Ogre3D" engine which does a bunch of memory management automatically. Basically, when I compile, it tells me it's missing operator delete, because Ogre overloads operator new or something I don't completely understand... I'm okay with serializing the BasicMesh, and then just recreating the RenderableMesh when it's deserialized. Which is what I'm going to have to do anyways because I don't want to change the Ogre3D SDK header files. It's probably super simple... If I don't implement it, it complains telling me the derived class is not registered... Which is correct. If I try to implement, it says operator delete is missing. Any ideas?

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[build] Cannot build from develop anymore
by Marcel Raad 19 Aug '14

19 Aug '14

Hi, last time I tried to build Boost from develop (a few weeks ago) with MSVC, it worked perfectly. Now I get the following errors on two different Windows 7 machines with both MSVC14 CTP3 and MSVC12.3: boost/tools/build/src/build\virtual-target.jam:1099: in virtual- target.register-actual-name from module virtual-target error: Duplicate name of actual target: <pstage\lib>libboost_system-vc140- mt-1_57.lib error: previous virtual target { common%common.copy-libboost_system-vc140- mt-1_57.lib.STATIC_LIB { msvc%msvc.archive-libboost_system-vc140- mt-1_57.lib.STATIC_LIB { msvc%msvc.compile.c++-error_code.obj.OBJ { error_code.cpp.CPP } } } } error: created from ./stage-proper error: another virtual target { common%common.copy-libboost_system-vc140- mt-1_57.lib.STATIC_LIB { msvc%msvc.archive-libboost_system-vc140- mt-1_57.lib.STATIC_LIB { msvc%msvc.compile.c++-error_code.obj.OBJ { error_code.cpp.CPP } } } } error: created from ./stage-proper error: added properties: <asynch-exceptions>on error: removed properties: <asynch-exceptions>off boost/tools/build/src/build\virtual-target.jam:484: in actualize-no-scanner from module object(file-target)@14375 boost/tools/build/src/build\virtual-target.jam:134: in class@virtual- target.actualize from module object(file-target)@14375 boost/tools/build/src\build-system.jam:720: in load from module build-system boost\tools\build\src/kernel\modules.jam:289: in import from module modules boost\tools\build\src/kernel/bootstrap.jam:139: in boost-build from module boost\boost-build.jam:17: in module scope from module Does anyone have any idea what Boost.Build is trying to tell me?

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Re: [Boost-users] boost serialisation, just including shared_ptr.hpp causes compile error on Linux/gcc 4.5
by avib369 . 19 Aug '14

19 Aug '14

Adding the two missing includes has indeed fixed the problem, as suggested in https://svn.boost.org/trac/boost/ticket/10348 #include <boost/serialization/singleton.hpp> #include <boost/serialization/extended_type_info.hpp> Thanks, Avi

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support for OpenMPI 64bit in modular-boost?
by Alle Meije Wink 19 Aug '14

19 Aug '14

Using the git repository (currently 1.57) of modular boost in Windows 7, compiling with MinGW64 and masm/ml64 (from the WDK v7) is successful but with the following warnings at the start: (1) warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam (2) warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. warning: No python installation configured and autoconfiguration note: failed. See http://www.boost.org/libs/python/doc/building.html note: for configuration instructions or pass --without-python to note: suppress this message and silently skip all Boost.Python targets After installing Open MPI 64-bit ( Windows installer of version 1.6.2 http://www.open-mpi.org/software/ompi/v1.6/downloads/OpenMPI_v1.6.2-2_win64… ), including adding it to the system-wide path, I have tried to re-build boost with MPI by, after running bootstrap gcc adding the line using mpi ; to the file project-config.jam in the boost directory (there is no file user-config.jam or a directory tools/build/v2 in the latest version or so it seems). Now the b2 command produces this output: The system cannot find the path specified. The system cannot find the path specified. The system cannot find the path specified. The system cannot find the path specified. The system cannot find the path specified. MPI auto-detection failed: unknown wrapper compiler mpic++ Please report this error to the Boost mailing list: http://www.boost.org You will need to manually configure MPI support. It continues to build the boost libraries, but still without MPI support. I am advised to manually configure MPI, but I'm pretty sure that is what I have just done. (the binaries are in the directory C:\Users\amwink\usr\local\OpenMPI_v1.6.2-x64\bin -- no spaces) Does anyone know what the problem is here? Is something wrong with this particular mpic++ binary that boost cannot handle? Happy to provide outputs/logs if that helps.

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boost serialisation, just including shared_ptr.hpp causes compile error on Linux/gcc 4.5
by avib369 . 18 Aug '14

18 Aug '14

I did not see boost serialisation in the list of lib that had changed. So its surprising that it now broken ? It appears simply including it cause problems #include <boost/serialization/shared_ptr.hpp> cause gcc.compile.c++ bin/gcc-4.5/debug/test/TestStr.o In file included from /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr.hpp:28:0, from test/TestStr.cpp:27: /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp: In static member function ‘static const boost::serialization::extended_type_info* boost::serialization::shared_ptr_helper<SPT>::non_polymorphic::get_object_type(U&)’: /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:107:22: error: ‘singleton’ is not a member of ‘boost::serialization’ /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:110:13: error: expected ‘(’ before ‘>’ token /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:110:14: error: ‘::get_const_instance’ has not been declared /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp: In static member function ‘static const boost::serialization::extended_type_info* boost::serialization::shared_ptr_helper<SPT>::polymorphic::get_object_type(U&)’: /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:117:20: error: ‘singleton’ is not a member of ‘boost::serialization’ /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:120:13: error: expected ‘(’ before ‘>’ token /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:120:14: error: ‘::get_const_instance’ has not been declared /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp: In member function ‘void boost::serialization::shared_ptr_helper<SPT>::reset(SPT<T>&, T*)’: /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:152:30: error: invalid use of incomplete type ‘const struct boost::serialization::extended_type_info’ /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:42:7: error: forward declaration of ‘const struct boost::serialization::extended_type_info’ /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:167:30: error: invalid use of incomplete type ‘const struct boost::serialization::extended_type_info’ /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:42:7: error: forward declaration of ‘const struct boost::serialization::extended_type_info’ /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:168:30: error: invalid use of incomplete type ‘const struct boost::serialization::extended_type_info’ /var/tmp/ma0/boost/boost_1_56_0/boost/serialization/shared_ptr_helper.hpp:42:7: error: forward declaration of ‘const struct boost::serialization::extended_type_info’ "g++" -ftemplate-depth-128 -fPIC -O0 -fno-inline -Wall -g -fPIC -DDEBUG -I"../ACore/src" -I"/var/tmp/ma0/boost/boost_1_56_0" -c -o "bin/gcc-4.5/debug/test/TestStr.o" "test/TestStr.cpp" Are there any workarounds ? Ta, Avi

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[BGL] Algorithm Objects
by Pierre Talbot 18 Aug '14

18 Aug '14

Hello, In the BGL documentation (challenge section, see http://www.boost.org/doc/libs/1_56_0/libs/graph/doc/challenge.html) a bullet point is: "Explore the use of Algorithm Objects as an alternative to the current approach with visitors." Do you have any links or explanations about the "Algorithm Objects" concept? Thanks, Pierre Talbot

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Boost.Xpressive
by Goran 17 Aug '14

17 Aug '14

Hi all, I'll have to check large CSV text files (up to several GB) and check them with Xpressive. As far as I can see, the only way to do is to load the whole file into a std::string and hand over to Xpressive. I don't want to do that because my files are too big. So, how can I open a CSV file in text mode, get bidirectional iterators and hand them over to Xpressive? Regards Goran

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[Serialization] 1.56.0 - polymorphic archive saving std::shared_ptr<>, no member named "get_helper"
by Todd Seiler 17 Aug '14

17 Aug '14

I'm trying to serialize a std::shared_ptr using a polymorphic archive interface, but it complains about no "get_helper". Specifically clang states: "<removed_for_posting>/boost_1_56_0/boost/serialization/shared_ptr.hpp:253:21: No member named 'get_helper' in 'boost::archive::polymorphic_iarchive'" I tried including "boost/serialization/shared_ptr_helper.hpp", but this didn't seem to have what I needed. I did see the new stuff in "boost/serialization/shared_ptr.hpp" regarding std::shared_ptr<>, so I'm hopeful. Most of what I'm doing requires the serialization code to be inside of dll's or dylibs, so I believe I'm going down the correct path in using polymorphic archives... void save(std::shared_ptr<developer> p) { std::ofstream of("archiv.txt"); boost::archive::polymorphic_text_oarchive oa(of); boost::archive::polymorphic_oarchive & oa_interface = oa; oa_interface << p; } void load() { std::ifstream i("archiv.txt"); boost::archive::polymorphic_text_iarchive ia(i); boost::archive::polymorphic_iarchive & ia_interface = ia; std::shared_ptr<developer> p; ia_interface >> p; std::cout << p->getName() << std::endl; std::cout << p->age() << std::endl; std::cout << p->language() << std::endl; std::cout << p->getLangVer() << std::endl; } The compiler error specifically points to this function in shared_ptr.hpp template<class Archive, class T> inline void load( Archive & ar, std::shared_ptr< T > &t, const unsigned int /*file_version*/ ){ // The most common cause of trapping here would be serializing // something like shared_ptr<int>. This occurs because int // is never tracked by default. Wrap int in a trackable type BOOST_STATIC_ASSERT((tracking_level< T >::value != track_never)); T* r; ar >> boost::serialization::make_nvp("px", r); boost::serialization::shared_ptr_helper<std::shared_ptr> & h = ar.template get_helper< shared_ptr_helper<std::shared_ptr> >(); h.reset(t,r); } Any suggestions?

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Do not understand about creating a vector of vector using Boost::interprocess libraries
by 张国熙 16 Aug '14

16 Aug '14

Dear everyone, I've just begun learning to use IPC in boost. Here I want to create a vector of vector<std::complex<double>>, that is to say, a matrix of complex. I read the section "containers of containers" in manual, and try to write something as the following: #include <boost/interprocess/containers/vector.hpp> #include <boost/interprocess/allocators/allocator.hpp> #include <boost/interprocess/managed_shared_memory.hpp> #include <complex> typedef boost::interprocess::allocator<std::complex<double>, boost::interprocess::managed_shared_memory::segment_manager> ComplexAllocator; typedef boost::interprocess::vector<std::complex<double>,ComplexAllocator> ComplexVector; typedef boost::interprocess::allocator<ComplexVector, boost::interprocess::managed_shared_memory::segment_manager> ComplexVectorAllocator; typedef boost::interprocess::vector<ComplexVector,ComplexVectorAllocator> ComplexMatrix; int main () { struct shm_remove { shm_remove() { boost::interprocess::shared_memory_object::remove("MySharedMemory"); } ~shm_remove(){ boost::interprocess::shared_memory_object::remove("MySharedMemory"); } } remover; boost::interprocess::create_only_t tag; boost::interprocess::managed_shared_memory segment(tag, "MySharedMemory", 65536); const ComplexVectorAllocator alloc_inst (segment.get_segment_manager()); ComplexMatrix *m = segment.construct<ComplexMatrix> ("M")(alloc_inst); m->resize(4); segment.destroy<ComplexMatrix>("M"); return 0; } However, it could not compile. And the error message is too long for me to understand. Is there anyone knowing how to fix this? Best wishes, Guoxi

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