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Re: [Boost-users] [multi_index] erasing elements
by Jeff Holle 11 Sep '07

11 Sep '07

Joaquín Mª López Muñoz wrote: > The two snippets of code you show are entirely equivalent, in the > sense that > Present inherits the functionality of its first index, YIndex. In > particular > YIndex::iterator is the *same type* as Present::iterator, so I'm > puzzled by the > fact that you're observing different behaviors --from the code you're > showing, > using one or the other variation cannot possibly make any difference > whatsoever. > Could you please check your code for some other differences you might > have not noticed when doing the switch from one version to the other? Thanks for this information. The two code snippets were not equivalent because I was only using the iterator returned from the multi_index container's erase method in the one using YIndex::iterators. I have found that this iterator doesn't point to an element in the container. Instead its pointing to some memory that is zeroed. Prior to erasing the element I inserted some test code that looks though the entire container and doesn't find such an element. Given my constructor, this only makes sense. Do you have an explanation?

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[Serialization] linking problems leading to unregistered class exception
by David Raulo 11 Sep '07

11 Sep '07

Hi, It seems I have linker-related problems leading to "unregistered class" exceptions being raised. Now, I know this sounds like a compilation chain-specific problem, but the thing is I get the exact same problem on Linux (Ubuntu 7.04, gcc4.1), Macosx 10.4 (gcc 4.0) and Windows (Microsoft Visual Studio 2005 Express). My initial problem was that I'm using Boost.Serialization on a rather big class hierarchy (around 200 classes), so instantiating all the serialization code in a single .cpp is not pratical (too much memory consumed by the compiler). So I split my BOOST_CLASS_EXPORT_GUID() declarations into several compilation units, and this worked fine. *Except* if I generate a static library, in which case I get unregistered class exceptions. If I take the same object files and link them into a dynamic library, or directly into my executable, then everything works as intended. So it looks like generating a static library (with gcc or msvc) leads to parts of the serialization code to disappear (a quick look at the file-size of the generated executables seems to confirm that). I attached the smallest test-case I could think of that reproduces this problem. The included Makefile will generate 3 executables: test_s11n, test_s11n_dyn, test_s11n_static. All of them build fine, but the last one fails at run-time. Anyone has some insight into this? Thanks, david.

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Unit Test Framework add
by Chris Miceli 11 Sep '07

11 Sep '07

I have had nothing but troubles with boost test 1.34.1 after switched from 1.33. First I had trouble with the main from shared object issue, and now my code that worked before is not executing a test added to the framework. #include <iostream> #define BOOST_TEST_DYN_LINK #define BOOST_TEST_MAIN #define BOOST_TEST_MODULE File Test #include <boost/bind.hpp> #include <boost/test/unit_test.hpp> template <typename Functor> struct my_test { void execute(int value) { //Never prints this message //Doesn't have to be a print, nothing gets here std::cerr << "Hi all" << std::endl << std::flush; } }; BOOST_AUTO_TEST_CASE( test123 ) { boost::shared_ptr<my_test<int> > tester(new my_test<int>); boost::unit_test::framework::master_test_suite().add(BOOST_TEST_CASE(boost::bind(&my_test<int>::execute, tester, 5))); } this worked when it was not using boost::bind but just the address of a normal function. This is just an simple version that illustrated the problem. I am compiling as such g++ test.cpp -o test -L/usr/local/lib -lboost_unit_test_framework-gcc41-mt This is the output: Running 1 test case... *** No errors detected

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XML Serialization
by tcmichals 11 Sep '07

11 Sep '07

Creating an application to send XML formatted data to this class that uses boost serialization, the issue is the name spaces in the boost_serialization tag; for example shown below... <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE boost_serialization > <boost_serialization xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" signature="serialization::archive" version="4">... looking at the rule for parsing, SerializationWrapper = !S >> str_p(L"<boost_serialization") >> S >> SignatureAttribute >> S >> VersionAttribute >> !S >> L'>' Is there a way to change the rules to allow skipping the namespaces? all of the elements are there but there are a few extra? The issue is trying to change the XML parser not to generate may not be possible .NET.

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Deciding parameter for adjancency list at runtime.
by abhishek.v＠tcs.com 11 Sep '07

11 Sep '07

Hi I have a function which take an input from the user whether the graph is directed or undirected. I'm declaring graph as follows :- typedef adjacency_list < vecS, vecS, undirectedS, property < vertex_name_t,std::string >, property < edge_name_t, std::string > > Graph; Graph g; Now here the parameter in Bold need to be varied as the user input changes. One method could be i could have two different function say,CreateDirected() and CreateUndirected(). But this is not working in my case as i want the declaration should be global so that i can use it throughout my application. Please help. Abhishek Vyas Tata Consultancy Services Mailto: abhishek.v(a)tcs.com Website: http://www.tcs.com ____________________________________________ Experience certainty. IT Services Business Solutions Outsourcing ____________________________________________ =====-----=====-----===== Notice: The information contained in this e-mail message and/or attachments to it may contain confidential or privileged information. If you are not the intended recipient, any dissemination, use, review, distribution, printing or copying of the information contained in this e-mail message and/or attachments to it are strictly prohibited. If you have received this communication in error, please notify us by reply e-mail or telephone and immediately and permanently delete the message and any attachments. Thank you

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Kamada kawai spring layout algorithm
by Meththa 11 Sep '07

11 Sep '07

Hi, I am a newbie to Boost and would like some help with implementing a program. I want to use the Kamada Kawai spring layout algorithm and I do not know what to pass for the final parameter when calling the function. the template of the function is given below. template<typename Graph, typename PositionMap, typename WeightMap, typename T, bool EdgeOrSideLength> bool kamada_kawai_spring_layout(const Graph & g, PositionMap position, WeightMap weight, unspecified edge_or_side_length); I do not understand what value needs to be given and what type for unspecified edge_or_side_length. Can someone please point me in the right direction with regards to this. Thanks ____________________________________________________________________________________Ready for the edge of your seat? Check out tonight's top picks on Yahoo! TV. http://tv.yahoo.com/

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BGL adaption question
by Andreas Fabri 11 Sep '07

11 Sep '07

Hello, I adapt my own graph like data structures. They form a derivation hierarchy, and they are all in the same graph category. In order to avoid that I have to repeat the specializations of the graph traits, I put all the types needed in the base class, so the default graph traits, which just takes the types out of the class it is applied to, will get them from the base class or via inherited types from the base class. What can I do in order to repeat the definition of the functions source(..), target(..) etc. I could tell my users to downcast but that's not nice. I also could have #defines for all my classes so that I write the code only once, but all these solutions are not appealing. any suggestion? andreas

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a question about message_queue
by nuaafantasy nuaafantasy 11 Sep '07

11 Sep '07

Dear All: My project use messge_queue to communicate between two processes. When I used the processes as normal process,it runs well. but It seems that the client process can't access the message queue if I set the server process as a windows services. can you help me about this? is this a problem about privilege? but message_queue do not have a option to set privileges. looking forward to your help!

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Smart pointers operator=
by Alessandro Re 11 Sep '07

11 Sep '07

Hi, can please someone explain me why in boost's smart pointers (and also in auto_ptr, if there is a reason), there is no operator=(T *)? Shouldn't it work like reset()? Thanks -- ~Ale

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If you are using the BGL and want to be listed here
by Andreas Fabri 11 Sep '07

11 Sep '07

Hello, On the page http://www.boost.org/libs/graph/doc/users.html it says: "If you are using the BGL and want to be listed here, please send mail to the Boost Users mailing list!" We would be glad if you added something like CGAL, the Computational Algorithms Library, offers external adaption for triangulations, polyhedral surfaces, and arrangements. These data structures become hence models of the BGL graph concept and allow to run BGL algorithms on them. http://www.cgal.org/Pkg/BGL Best regards, Andreas Fabri

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[multi_index] erasing elements
by Jeff Holle 11 Sep '07

11 Sep '07

I'm using boost::multi_index obtained via CVS on Fri Jun 29 12:30:03 EDT 2007. In my application, I'm using a multi_index container that has one ordered index. Call the container Present and the index YIndex. I'm at the point in which I need to erase an element which returns a YIndex::iterator. Its important that I know the neighbors of the element erased with respect to the YIndex. I know that the element which I look for in the container must exist, so I have an assert that will fail if the searched for element isn't found. If I code it like this: YIndex& index=m_present.get<0>(); YIndex::iterator iter = index.begin(); for (;iter!=index.end();++iter) if (m_future.top().getEdges().first == iter->getEdge()) break; assert(iter!=index.end()); iter = index.erase(iter); The assert goes off the 4th time this code runs. If I change the code to this: Present::iterator iter = m_present.begin(); for (;iter!=m_present.end();++iter) if (m_future.top().getEdges().first == iter->getEdge()) break; assert(iter!=m_present.end()); iter = m_present.erase(iter); The application runs to completion, but since I need YIndex::iterators I can't code what is needed by my application. I'm assuming that calling erase corrupts the ordered index. What do I have to do to correct this?

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[spirit]how to ignore the sequence of the rules?
by moosefly 11 Sep '07

11 Sep '07

For example, I want to parse the following text: <input type=hidden value=1> I have defined 2 rules match the "type" field and the "value" field, but the sequence of 2 rules is uncertain, that means "<input value=1 type=hidden>" is also legal,so I can't define the rules just like: rule_type >> !space_p >> rule_value The following works at this simple condition: ( (rule_type >> !space_p >> rule_value) | (rule_value >> !space_p >>rule_type ) ) But if there are many out-of-order fields need to parser, how can I ignore the sequence of the rules? Thanks, moosefly

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Creating directory structure recursively using create_directories()
by Rajesh Jadhav 10 Sep '07

10 Sep '07

Hello All, I am trying to create a directory structure having 4 to 5 levels. When I try to call the boost::filesystem::create_directories(src); It throws an exception saying that path does not exist .So isn't create_directories() mean't for creating directory structure recursively or is there a other api which does it. I could not find Api's which can split the path ,and give the directory names in the path starting after the root directory up to leaf directory . I am attaching the sample code . #include <iostream> #include "boost/filesystem/operations.hpp" #include "boost/filesystem/path.hpp" #include "boost/filesystem/convenience.hpp" int main() { const char* srcPath = "C:\\tmp\\dir1\\dir2\\dir3\\"; (this structure does not exist) boost::filesystem::path src = boost::filesystem::path(srcPath, boost::filesystem::no_check); try { boost::filesystem::create_directories(relativepath); // throws exception if(src.has_branch_path()) { boost::filesystem::path branchpath = src.branch_path(); std::cout << branchpath.string(); // prints C: boost::filesystem::path rootpath = src.root_path(); std::cout << rootpath.string(); //prints C: boost::filesystem::path relativepath = src.relative_path(); std::cout << relativepath.string(); //prints tmp\\dir1\\dir2\\dir3\\ } } catch(std::exception& ex) { std::cout << ex.what() << std::endl; } return 0; } Thanks in advance for the replies. Rajesh

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[serialization] improved demo_shared_ptr.cpp using XML archive
by Robbie Morrison 10 Sep '07

10 Sep '07

Hello all The 'demo_shared_ptr.cpp' example currently bundled with the Boost documentation has some problems. It would not compile without modification on my system (g++ 4.1/Ubuntu 6.10). And it took quite some work to make XML the archive format if one is not familiar with the Boost.Serialization library. The code below, I hope, represents an improvement. I will happily take on-board any suggestions and fixes (descriptive or diffs as suits) and will resubmit a modified example back to this list in due course. Furthermore, it may be appropriate to add the final version of this file to the official Boost documentation. Alternatively, I can put it on the Boost Wiki as an unofficial contribution. (Perhaps Robert can advise on which approach would be better?) Finally, some search terms which might help locate this posting: unregistered void cast sp_counted_base_impl oa.register_type with best wishes Robbie --- Robbie Morrison PhD student -- policy-oriented energy system simulation Institute for Energy Engineering (IET) Technical University of Berlin (TU-Berlin), Germany 8<--------------------------------------------------------------- // demo_shared_ptr_xml.cpp : demos polymorphic pointer XML serialization // ******************************************************************* // MODIFICATION WARNING: this file has been modified by a Boost user // and is not part of the official Boost distribution. // ******************************************************************* // (C) Copyright 2002 Robert Ramey - http://www.rrsd.com . Polymorphic // derived pointer example by David Tonge. XML archive format and bug // fixes added by Robbie Morrison <robbie(a)actrix.co.nz> on 10-Sep-2007. // Use, modification and distribution is subject to the Boost Software // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) // // See http://www.boost.org for updates, documentation, and revision history. // // Purpose // // This file demonstrates how base class pointers holding derived // class objects can be serialized and deserialized in one of // three archive formats: text, XML, and platform-specific binary. // // Important // // Note carefully that, in this example, the class hierarchy is // "polymorphic", which means that each parent class definition // contains at least one virtual function -- in this case, its // destructor. // // Base classes can also be abstract. Users may wish to // experiment by making class A abstract, in which case, the // following macro should be placed after the duly revised class // definition: BOOST_IS_ABSTRACT(A) // // Note also that a non-polymorphic class hierarchy will not // serialize derived instances without extra effort. In most // cases, it is simpler and less error-prone to declare all // relevant destructors as virtual. // // Text and binary archive formats can be selected by // redefining the ARCHIVE_FORMAT preprocessor macro in the // code below. The default format is XML. // // XML is a little more demanding code-wise because both the // object itself and a legal XML tag name need to be // specified. Often the simplest way to do this is to use a // Boost macro which automatically generates the tag name // from the C++ identifier, such as BOOST_SERIALIZATION_NVP(x) // and BOOST_SERIALIZATION_BASE_OBJECT_NVP(A). // // Testing // // This file has been tested with Boost release 1.34.1 dated // 24-Jul-2007 (source build) and also release 1.33.1 (Ubuntu // package) using the GNU GCC 4.1.2 compiler (with -Wall and // -pedantic), valgrind version "valgrind-3.2.0-Debian" memory // checker, and Linux Ubuntu 6.10 operating system (now superseded // by 7.04). The file builds and runs cleanly under the // conditions just listed. #include <iostream> // standard io #include <fstream> // file-based io #include <string> // C++ strings #include <boost/archive/tmpdir.hpp> // locate a temporary directory #include <boost/archive/text_oarchive.hpp> // save text archive #include <boost/archive/text_iarchive.hpp> // load text archive #include <boost/archive/xml_oarchive.hpp> // save XML archive #include <boost/archive/xml_iarchive.hpp> // load XML archive #include <boost/archive/binary_oarchive.hpp> // save non-portable binary archive #include <boost/archive/binary_iarchive.hpp> // load non-portable binary archive #include <boost/serialization/serialization.hpp> // friendship #include <boost/serialization/shared_ptr.hpp> // shared_ptr serialization #include <boost/serialization/base_object.hpp> // base class serialization #include <boost/serialization/is_abstract.hpp> // BOOST_IS_ABSTRACT macro #include <boost/serialization/export.hpp> // BOOST_CLASS_EXPORT macro (place last) // set some typedefs to enable the client code to shift between // archive formats without further effort (if you don't need this // flexibility, omit these typedefs and just use the original // type names, also remove any library headers that are now // surplus to requirements) // // 1 = text format, 2 = XML format, 3 = binary format #define ARCHIVE_FORMAT 2 #if (ARCHIVE_FORMAT == 1) typedef boost::archive::text_oarchive output_archive_type; typedef boost::archive::text_iarchive input_archive_type; const std::string archive_ext = "txt"; #elif (ARCHIVE_FORMAT == 2) typedef boost::archive::xml_oarchive output_archive_type; typedef boost::archive::xml_iarchive input_archive_type; const std::string archive_ext = "xml"; #elif (ARCHIVE_FORMAT == 3) typedef boost::archive::binary_oarchive output_archive_type; typedef boost::archive::binary_iarchive input_archive_type; const std::string archive_ext = "dat"; #endif // class A is a polymorphic base class, due to its virtual destructor class A { friend class boost::serialization::access; // intrusive serialization private: template <class Archive> void serialize (Archive& ar, const unsigned int class_version) { ar & BOOST_SERIALIZATION_NVP(x); // macro form //ar & boost::serialization::make_nvp("x", x); // statement form } int x; public: A(): x(42) { ++count; } // default constructor, the 42 is arbitrary virtual ~A() { --count; } static int count; // public to simplify test code (although not used) }; // the following macro is needed for derived classes, but does no harm for base classes // BOOST_CLASS_EXPORT(A) // requires <boost/serialization/export.hpp> // uncomment if making class A abstract (left as an exercise for users) // BOOST_IS_ABSTRACT(A) // requires <boost/serialization/is_abstract.hpp> // uncomment if using particular Metrowerks or Borland compilers // BOOST_SERIALIZATION_SHARED_PTR(A) int A::count = 0; // derived class B was originally added by David Tonge class B : public A { friend class boost::serialization::access; private: template<class Archive> void serialize(Archive& ar, const unsigned int class_version) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(A); // this works fine in all cases //ar & boost::serialization::base_object<A>(*this); // CAUTION: problematic for XML ar & BOOST_SERIALIZATION_NVP(x); } int x; public: B() : x(84) { ++count; } // default constructor, the 84 is arbitrary virtual ~B() { --count; } static int count; }; // uncomment if using particular Metrowerks or Borland compilers // BOOST_SERIALIZATION_SHARED_PTR(B) // if omitted, an "unregistered class" boost::archive::archive_exception is thrown BOOST_CLASS_EXPORT(B) // strictly necessary as B is derived int B::count = 0; // display details for two supposedly common shared pointers void display(std::string tag, boost::shared_ptr<A>& a0, boost::shared_ptr<A>& a1) { std::cout << tag << "0: address = 0x" << std::hex << a0.get() << std::dec; if (a0.get()) std::cout << ", underlying typeid = " << typeid(*(a0.get())).name(); std::cout << ", use_count = " << a0.use_count() << std::endl; std::cout << tag << "1: address = 0x" << std::hex << a1.get() << std::dec; if (a1.get()) std::cout << ", underlying typeid = " << typeid(*(a1.get())).name(); std::cout << ", use_count = " << a1.use_count() << std::endl; std::cout << std::endl; } // main code int main(int argc, char* argv[]) { // name the archive file std::string filename(boost::archive::tmpdir()); //locate a temporary directory filename += "/demo_shared_ptr_xml."; // filename stub filename += archive_ext; // "txt", "xml", "dat" const char* cfilename = filename.c_str(); // convert to C-stye string // part one std::cout << std::endl; std::cout << "original pointers" << "\n" << std::endl; // create two new type A shared pointers to hold a single type A object boost::shared_ptr<A> spa0(new A()); // spa0(new A) would also be acceptable boost::shared_ptr<A> spa1; spa1 = spa0; // both now own the same type A object display("spa", spa0, spa1); // new code by David Tonge starts here // create two new type A shared pointers to hold a single type B object boost::shared_ptr<A> spb0(new B()); // a derived and also polymorphic pointer boost::shared_ptr<A> spb1; spb1 = spb0; display("spb", spb0, spb1); // serialize the four pointers // // it would be better practice to make the following block a // try block and then catch exceptions (but this code has // been omitted for reasons of simplicity) { std::ofstream ofs(cfilename, std::ios::binary); output_archive_type oa(ofs); // see earlier typedefs oa << BOOST_SERIALIZATION_NVP(spa0); oa << BOOST_SERIALIZATION_NVP(spa1); oa << BOOST_SERIALIZATION_NVP(spb0); oa << BOOST_SERIALIZATION_NVP(spb1); // 'ofs' and 'oa' are automatically destructed on exiting this block } // part two std::cout << "reset pointers" << "\n" << std::endl; // reset each shared pointer to hold a type A* null pointer spa0.reset(); spa1.reset(); // last shared pointer, held object duly deallocated spb0.reset(); spb1.reset(); // last shared pointer, held object duly deallocated display("spa", spa0, spa1); display("spb", spb0, spb1); // part three std::cout << "reinstated pointers" << "\n" << std::endl; // restore program state to one equivalent to the original { std::ifstream ifs(cfilename, std::ios::binary); input_archive_type ia(ifs); ia >> BOOST_SERIALIZATION_NVP(spa0); ia >> BOOST_SERIALIZATION_NVP(spa1); ia >> BOOST_SERIALIZATION_NVP(spb0); ia >> BOOST_SERIALIZATION_NVP(spb1); } display("spa", spa0, spa1); display("spb", spb0, spb1); // report archive name std::cout << "archive name: " << filename << "\n" << std::endl; return 0; } // main() // --------------------------------- // Output (typeid is compiler-dependent) // --------------------------------- // // original pointers // // spa0: address = 0x0x4e719e0, underlying typeid = 1A, use_count = 2 // spa1: address = 0x0x4e719e0, underlying typeid = 1A, use_count = 2 // // spb0: address = 0x0x4e71a98, underlying typeid = 1B, use_count = 2 // spb1: address = 0x0x4e71a98, underlying typeid = 1B, use_count = 2 // // reset pointers // // spa0: address = 0x0, use_count = 0 // spa1: address = 0x0, use_count = 0 // // spb0: address = 0x0, use_count = 0 // spb1: address = 0x0, use_count = 0 // // reinstated pointers // // spa0: address = 0x0x4e7b308, underlying typeid = 1A, use_count = 2 // spa1: address = 0x0x4e7b308, underlying typeid = 1A, use_count = 2 // // spb0: address = 0x0x4e7c600, underlying typeid = 1B, use_count = 2 // spb1: address = 0x0x4e7c600, underlying typeid = 1B, use_count = 2 // // archive name: ./demo_shared_ptr_xml.xml // end-of-file demo_shared_ptr_xml.cpp --------------------------------------------------------------->8 [from IMAP client]

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xor (^) operator for matrix rows
by Florian Hug 10 Sep '07

10 Sep '07

Hello, let's say you have the following function void combine(boost::numeric::ublas::matrix<int> &m) { row(m, 1) += row(m, 2); } works great and adds the second row to the first one. But trying to xor the individual integers by using void combine(boost::numeric::ublas::matrix<int> &m) { row(m, 1) += row(m, 2); } fails, because the ^ operator isn't defined. In boost/numeric/ublas/matrix_proxy.hpp I've found the definitions of the plus, minus etc operators but at the moment I don't know what I have to define there. Can anybody help? Thanks a lot Florian

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[Type Traits] is_base_of with incomplete types
by Johan Råde 10 Sep '07

10 Sep '07

When is_base_of is "called" with an incomplete type, then it may silently "return" an incorrect result. Would it not be better if is_base_of failed to compile with incomplete types? Johan Råde CTO, Qlucore AB

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circle layout
by Meththa 10 Sep '07

10 Sep '07

Hi, I need help with implementing the circle_layout. I am using this inorder to implement the kamada_kawai_spring_layout function. I want to check if how the circle_layout works and would like to output the coordinates of the vertices so that I can check this. I cannot seem to find any place where this algorithm is used and would like to know if anyone else has used it and found a way to display the output. Your help is much appreciated. ____________________________________________________________________________________ Pinpoint customers who are looking for what you sell. http://searchmarketing.yahoo.com/

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Ideas Wanted: How best to configure Boost.TR1 with GCC?
by John Maddock 10 Sep '07

10 Sep '07

Folks, I have a configuration problem I don't know how to solve, so I'm soliciting for ideas. Here's the basic problem: Boost.TR1 has to replace some of the std library headers, and forward to the existing "real" ones. To do this it can either: 1) Use #include_next to forward to the real std lib header. 2) Use #include <../some_directory/header_name> to forward to the std lib header. Up until now, I've been using #1 with GCC, unfortunately if Boost is installed in /usr/include then it doesn't work: because the Boost include path appears *after* the std library one rather than before it. So... in response to a bug-report I recently changed it to method 2 (on Linux anyway), using the same configuration logic as STLport to determine what "some_directory" is called. Having tested it locally with several gcc versions on Linux everything seemed fine... except it's not: the problem is that gcc has a configuration option that lets you change the name of the directory the headers go in, and several Linux distro's change it from the default, so instead of being the normal default of something like "4.2.0" it's g++-v4 or something else that we can't automatically deduce :-( Obviously I could add a user-config macro for this purpose, but it's all a real pain basically :-( Anyone any better ideas? Or should I give up before I loose the will to live ! ;-) Thanks! John.

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[mpl] Newbie question - working with sets
by Dan Posluns 09 Sep '07

09 Sep '07

I've been trying to use MPL to create a system on an embedded platform (where memory is at a premium and dynamic allocations are expensive) that allows for multiple components or properties to be combined into a single object at both compile and run-time. The basic idea is, say I have the following properties for a 3D model (each its own independent class; there are more than the examples I list here): ModelBase Configuration JointAnimation TextureAnimation LightingConfig I know that a box doesn't need JointAnimation, so when I instantiate a Model for it I'd like it to not have that "property". (I could easily accomplish all of this using a std::map and a dynamic allocation for each property, but again, it's prohibitive on the platform and I'd rather use metaprogramming if I can.) So what I'd like to do, in theory, is something like: // Declare a generic class for a property-based object that templates off of the set of properties it can contain template<class PropertiesSet> class ObjectWithProperties { public: // Create an instance of ObjectWithProperties, using some subset of PropertiesSet template<class PropertiesSubset> static ObjectWithProperties *create(); // Attempt to retrieve a Property, return null on failure template<class PropertyType> PropertyType *getProperty(); private: SomeStaticListManager< size<PropertiesSet>::value > which_properties_are_used; void *data_buffer_for_properties; }; // Define the set of properties that a model can consist of typedef set<ModelBase, Configuration, JointAnimation, TextureAnimation, LightingConfig> ModelPropertiesSet; // Define a Model as an object with those properties typedef ObjectWithProperties<ModelPropertiesSet> Model; // Instantiate a model with only certain properties: Model *m = Model::Create< set<ModelBase, Configuration> >(); // A Model that only has two properties The Create() method would iterate over the subset, tally up the sizeof() for each class, and then perform a single allocation for data_buffer_for_properties and proceed to use placement new to instantiate each class in the subset. (The destructor would then clean up all of that ugliness.) The which_properties_are_used member would be an efficient list manager that can be used to lookup the existence of properties, indexing the types in the set using the order<> operator. Unfortunately, I haven't been able to get very far with set<>. I tried the following: typedef fold< PropertiesSubset, int_<0>, plus< _1, sizeof_<_2> > >::type TotalSize; cout << TotalSize::value; ... and it gives me nothing like what I'm looking for. The documentation hasn't been much help, and I haven't even begun to attempt iterating an actual function over the set (would that be for_each<>?). Any help or ideas to alternative approaches would be greatly appreciated! Thanks, Dan. -- Dan Posluns, B. Eng. & Scty. (Software Engineering and Society) dan(a)danposluns.com - ICQ: 35758902 http://www.danposluns.com "The great thing about being the only species on the planet that makes a distinction between right and wrong is that we get to make the rules up for ourselves as we go." - Douglas Adams, Last Chance to See

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Re: [Boost-users] [Serialization] New user: serializing base class
by Len Berman 09 Sep '07

09 Sep '07

Hi Robert, I'm a bit confused about the slicing problem. I didn't think slicing would occur because the argument to Archive's operator<< is a reference argument; however, I had been expecting the template serialize to behave like a virtual function and, of course, it doesn't. I took a different approach, writing a small main (below) which merely serializes a bus_route. I add the bus_stop_corner to the bus_route and everything works as I expected. The bus_route is saved with the information from the derived class and the class is restored correctly to the derived class. Similarly, if I serialize &bs0 directly, everything is OK. This leasds me hope that it should be possible to serialize the object, bs0, directly since it is a reference to the base class part of a bus_stop_corner. Having a big difference between a reference and a pointer feels to me that there is some symmetry lacking which means that I am not understanding something fundamental. It should be possible to write something like ar << bs0, and have the information associated with the derived class be saved. Is this what you were referring to as the slicing problem. This seems very strange to me: I add &bs0 to the bus_route or serialize it directly and it serializes correctly, i.e. with the derived class info, and yet there is no way to serialize the object, bs0, directly and also get the derived class. It looks like all of the arguments are reference arguments so this is different than what I usually think of as slicing. Can you help me understand this? Thanks. --Len int main(int argc, char *argv[]) { // fill in the data // make a few stops const bus_stop_corner *bsc0 = new bus_stop_corner(gps_position(34, 135, 52.560f),gps_position(134, 22, 78.30f),"24th Street", "10th Avenue"); const bus_stop& bs0(*bsc0); bus_route br; br.append( const_cast<bus_stop*> (&bs0) ); br.append( dynamic_cast<bus_stop*>( const_cast<bus_stop_corner*> (bsc0)) ); { std::ofstream ofs("demofile1.txt"); boost::archive::text_oarchive oa(ofs); // oa << const_cast<const bus_route&>(br); oa & br; std::cout << "br" << std::endl << br; } std::ifstream ifs("demofile1.txt"); boost::archive::text_iarchive ia(ifs); //oa << *bsc0; bus_route brN; // ia & brN; compiles whether & or >> is used ia >> brN; std::cout << "brN" << std::endl << brN ; } Thanks again. --Len Robert Ramey wrote: > I think there is a misconception here. Consider the following: > > bus_stop * bs = new bus_stop_corner(0) > > // bs now contains a pointer to the base class portion of the derived > object. > // so far so good. > > bus_stop bs1 = *bs; > > // bs1 contains a copy of just the base class portion of the original > derived object. > // The derived portion has been lost. This is referred to as "object > slicing" > > // the following operation > > ar << *bs > > // is equivalent to > > bs1 = *bs > ar << bs1 > > // which will lose the derived portion of the class > > The best way to avoid this problem is to make base classes "abstract > by making at least on virtual function (may just the destructor) = 0. > > This will detect the problem at compile time. > > Robert Ramey > > > Len Berman wrote: >> Hi, >> >> I am trying to understand the differences between intrusive and >> non-intrusive style of serialization for derived classes. The >> classes I want to serialize look like: >> >> class Base {} >> template<class TYPE> class Derived : public Base , public >> std::vector<TYPE> {} >> >> where it is intended that TYPE is a built in C type (int, double, ...) >> >> I'm starting by trying to understand the demo.cpp example since that >> example serializes derived classes. >> >> My first goal is to serialize bus_stop_corner and >> bus_stop_destination directly through the base class. These are >> serialized through a pointer indirectly when bus_stop_schedule is >> serialized; however, I've been unable to do this directly. I've gone >> about it using the pseudo-code in 'Pointers to Objects of Derived >> Classes'; however, I get the following compilation error: >> >> g++ -g demo2.cpp -o demo2 /usr/lib/libboost_serialization.a >> >> (I'm using g++ (GCC) 4.1.2 20061115 (prerelease) (Debian 4.1.1-21)) >> >> /usr/include/boost/archive/detail/oserializer.hpp: In function >> $-1òøvoid boost::archive::save(Archive&, T&) [with Archive = >> boost::archive::text_oarchive, T = bus_stop*]òù: >> /usr/include/boost/archive/basic_text_oarchive.hpp:78: instantiated >> from $-1òøvoid >> boost::archive::basic_text_oarchive<Archive>::save_override(T&, int) >> [with T = bus_stop*, Archive = boost::archive::text_oarchive]òù >> /usr/include/boost/archive/detail/interface_oarchive.hpp:78: >> instantiated from $-1òøArchive& >> boost::archive::detail::interface_oarchive<Archive>::operator<<(T&) >> [with T = bus_stop*, Archive = boost::archive::text_oarchive]òù >> demo2.cpp:164: instantiated from here >> /usr/include/boost/archive/detail/oserializer.hpp:567: error: invalid >> application of $-1òøsizeofòù to incomplete type >> òøboost::STATIC_ASSERTION_FAILURE<false>òù >> >> I've also tried by taking the full demo.cpp, and creating a function, >> save_stop, modeled after save_schedule. This compiles but saves only >> the base class. This larger piece of code is below, after >> ++++++++++++++++++. Differences from demo.cpp are marked with //<<<< >> >> Obviously, I'm missing something; hopefully, something simple. >> >> Any help greatly appreciated. >> >> Thanks. >> --Len >> >> /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8 >> >> // demo.cpp >> // >> // (C) Copyright 2002-4 Robert Ramey - http://www.rrsd.com . >> // Use, modification and distribution is subject to the Boost Software >> // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or >> copy at >> // http://www.boost.org/LICENSE_1_0.txt) >> >> >> #include <iomanip> >> #include <iostream> >> #include <fstream> >> #include <string> >> >> #include <boost/archive/tmpdir.hpp> >> >> #include <boost/archive/text_iarchive.hpp> >> #include <boost/archive/text_oarchive.hpp> >> >> #include <boost/serialization/base_object.hpp> >> #include <boost/serialization/utility.hpp> >> #include <boost/serialization/list.hpp> >> >> class gps_position >> { >> friend std::ostream & operator<<(std::ostream &os, const >> gps_position &gp); >> friend class boost::serialization::access; >> int degrees; >> int minutes; >> float seconds; >> template<class Archive> >> void serialize(Archive & ar, const unsigned int /* file_version >> */){ >> ar & degrees & minutes & seconds; >> } >> public: >> // every serializable class needs a constructor >> gps_position(){}; >> gps_position(int _d, int _m, float _s) : >> degrees(_d), minutes(_m), seconds(_s) >> {} >> }; >> std::ostream & operator<<(std::ostream &os, const gps_position &gp) >> { >> return os << ' ' << gp.degrees << (unsigned char)186 << gp.minutes >> << '\'' << gp.seconds << '"'; >> } >> >> ///////////////////////////////////////////////////////////// >> // One bus stop >> // >> // illustrates serialization of serializable members >> // >> >> class bus_stop_corner; >> class bus_stop_destination; >> >> class bus_stop >> { >> friend class boost::serialization::access; >> friend std::ostream & operator<<(std::ostream &os, const bus_stop >> &gp); >> virtual std::string description() const = 0; >> gps_position latitude; >> gps_position longitude; >> template<class Archive> >> void serialize(Archive &ar, const unsigned int version) { >> // register all derived classes. >> ar.register_type(static_cast<bus_stop_corner>(NULL)); >> ar.register_type(static_cast<bus_stop_destination>(NULL)); >> ar & latitude; >> ar & longitude; >> } >> protected: >> bus_stop(const gps_position & _lat, const gps_position & _long) : >> latitude(_lat), longitude(_long) >> {} >> public: >> bus_stop(){} >> // virtual void serialize(std::ostream &ar, const unsigned int >> file_version) = 0; >> virtual ~bus_stop(){} >> }; >> >> BOOST_IS_ABSTRACT(bus_stop) >> >> std::ostream & operator<<(std::ostream &os, const bus_stop &bs) >> { >> return os << bs.latitude << bs.longitude << ' ' << >> bs.description(); >> } >> >> ///////////////////////////////////////////////////////////// >> // Several kinds of bus stops >> // >> // illustrates serialization of derived types >> // >> class bus_stop_corner : public bus_stop >> { >> friend class boost::serialization::access; >> std::string street1; >> std::string street2; >> virtual std::string description() const >> { >> return street1 + " and " + street2; >> } >> template<class Archive> >> void serialize(Archive &ar, const unsigned int version) >> { >> // save/load base class information >> ar & boost::serialization::base_object<bus_stop>(*this); >> ar & street1 & street2; >> } >> >> public: >> bus_stop_corner(){} >> // virtual void serialize(std::ostream &ar, const unsigned int >> file_version){ >> // ar << "bus_stop_corner"; >> // }; >> bus_stop_corner(const gps_position & _lat, const gps_position & >> _long, >> const std::string & _s1, const std::string & _s2 >> ) : >> bus_stop(_lat, _long), street1(_s1), street2(_s2) >> { >> } >> }; >> >> class bus_stop_destination : public bus_stop >> { >> friend class boost::serialization::access; >> std::string name; >> virtual std::string description() const >> { >> return name; >> } >> template<class Archive> >> void serialize(Archive &ar, const unsigned int version) >> { >> description(); >> ar & boost::serialization::base_object<bus_stop>(*this) & name; >> } >> public: >> >> bus_stop_destination(){} >> // virtual void serialize(std::ostream &ar, const unsigned int >> file_version){ >> // ar << "bus_stop_destination"; >> // }; >> bus_stop_destination( >> const gps_position & _lat, const gps_position & _long, const >> std::string & _name >> ) : >> bus_stop(_lat, _long), name(_name) >> { >> } >> }; >> >> int main(int argc, char *argv[]) >> { >> // fill in the data >> // make a few stops >> bus_stop_corner *bsc0; >> bus_stop *bs0 = bsc0 = new bus_stop_corner( >> gps_position(34, 135, 52.560f), >> gps_position(134, 22, 78.30f), >> "24th Street", "10th Avenue" >> ); >> >> std::ofstream ofs("demofile1.txt"); >> boost::archive::text_oarchive oa(ofs); >> oa << bs0; >> } >> >> ++++++++++++++++++++++++++++++++++++++ >> >> /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8 >> >> // demo.cpp >> // >> // (C) Copyright 2002-4 Robert Ramey - http://www.rrsd.com . >> // Use, modification and distribution is subject to the Boost Software >> // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or >> copy at >> // http://www.boost.org/LICENSE_1_0.txt) >> >> >> #include <iomanip> >> #include <iostream> >> #include <fstream> >> #include <string> >> >> #include <boost/archive/tmpdir.hpp> >> >> #include <boost/archive/text_iarchive.hpp> >> #include <boost/archive/text_oarchive.hpp> >> >> #include <boost/serialization/base_object.hpp> >> #include <boost/serialization/utility.hpp> >> #include <boost/serialization/list.hpp> >> >> ///////////////////////////////////////////////////////////// >> // The intent of this program is to serve as a tutorial for >> // users of the serialization package. An attempt has been made >> // to illustrate most of the facilities of the package. >> // >> // The intent is to create an example suffciently complete to >> // illustrate the usage and utility of the package while >> // including a minimum of other code. >> // >> // This illustration models the bus system of a small city. >> // This includes, multiple bus stops, bus routes and schedules. >> // There are different kinds of stops. Bus stops in general will >> // will appear on multiple routes. A schedule will include >> // muliple trips on the same route. >> >> ///////////////////////////////////////////////////////////// >> // gps coordinate >> // >> // llustrates serialization for a simple type >> // >> class gps_position >> { >> friend std::ostream & operator<<(std::ostream &os, const >> gps_position &gp); >> friend class boost::serialization::access; >> int degrees; >> int minutes; >> float seconds; >> template<class Archive> >> void serialize(Archive & ar, const unsigned int /* file_version >> */){ >> ar & degrees & minutes & seconds; >> } >> public: >> // every serializable class needs a constructor >> gps_position(){}; >> gps_position(int _d, int _m, float _s) : >> degrees(_d), minutes(_m), seconds(_s) >> {} >> }; >> std::ostream & operator<<(std::ostream &os, const gps_position &gp) >> { >> return os << ' ' << gp.degrees << (unsigned char)186 << gp.minutes >> << '\'' << gp.seconds << '"'; >> } >> >> ///////////////////////////////////////////////////////////// >> // One bus stop >> // >> // illustrates serialization of serializable members >> // >> >> >> class bus_stop >> { >> friend class boost::serialization::access; >> friend std::ostream & operator<<(std::ostream &os, const bus_stop >> &gp); >> virtual std::string description() const = 0; >> gps_position latitude; >> gps_position longitude; >> template<class Archive> >> void serialize(Archive &ar, const unsigned int version) >> { >> ar & latitude; >> ar & longitude; >> } >> protected: >> bus_stop(const gps_position & _lat, const gps_position & _long) : >> latitude(_lat), longitude(_long) >> {} >> public: >> bus_stop(){} >> virtual ~bus_stop(){} >> }; >> >> BOOST_IS_ABSTRACT(bus_stop) >> >> std::ostream & operator<<(std::ostream &os, const bus_stop &bs) >> { >> return os << bs.latitude << bs.longitude << ' ' << >> bs.description(); >> } >> >> ///////////////////////////////////////////////////////////// >> // Several kinds of bus stops >> // >> // illustrates serialization of derived types >> // >> class bus_stop_corner : public bus_stop >> { >> friend class boost::serialization::access; >> std::string street1; >> std::string street2; >> virtual std::string description() const >> { >> return street1 + " and " + street2; >> } >> template<class Archive> >> void serialize(Archive &ar, const unsigned int version) >> { >> // save/load base class information >> ar & boost::serialization::base_object<bus_stop>(*this); >> ar & street1 & street2; >> } >> >> public: >> bus_stop_corner(){} >> bus_stop_corner(const gps_position & _lat, const gps_position & >> _long, >> const std::string & _s1, const std::string & _s2 >> ) : >> bus_stop(_lat, _long), street1(_s1), street2(_s2) >> { >> } >> }; >> >> class bus_stop_destination : public bus_stop >> { >> friend class boost::serialization::access; >> std::string name; >> virtual std::string description() const >> { >> return name; >> } >> template<class Archive> >> void serialize(Archive &ar, const unsigned int version) >> { >> description(); >> ar & boost::serialization::base_object<bus_stop>(*this) & name; >> } >> public: >> >> bus_stop_destination(){} >> bus_stop_destination( >> const gps_position & _lat, const gps_position & _long, const >> std::string & _name >> ) : >> bus_stop(_lat, _long), name(_name) >> { >> } >> }; >> >> ///////////////////////////////////////////////////////////// >> // a bus route is a collection of bus stops >> // >> // illustrates serialization of STL collection templates. >> // >> // illustrates serialzation of polymorphic pointer (bus stop *); >> // >> // illustrates storage and recovery of shared pointers is correct >> // and efficient. That is objects pointed to by more than one >> // pointer are stored only once. In such cases only one such >> // object is restored and pointers are restored to point to it >> // >> class bus_route >> { >> friend class boost::serialization::access; >> friend std::ostream & operator<<(std::ostream &os, const bus_route >> &br); >> typedef bus_stop * bus_stop_pointer; >> std::list<bus_stop_pointer> stops; >> template<class Archive> >> void serialize(Archive &ar, const unsigned int version) >> { >> // in this program, these classes are never serialized >> directly but rather >> // through a pointer to the base class bus_stop. So we need a >> way to be >> // sure that the archive contains information about these >> derived classes. >> //ar.template register_type<bus_stop_corner>(); >> ar.register_type(static_cast<bus_stop_corner *>(NULL)); >> //ar.template register_type<bus_stop_destination>(); >> ar.register_type(static_cast<bus_stop_destination *>(NULL)); >> // serialization of stl collections is already defined >> // in the header >> ar & stops; >> } >> public: >> bus_route(){} >> void append(bus_stop *_bs) >> { >> stops.insert(stops.end(), _bs); >> } >> }; >> std::ostream & operator<<(std::ostream &os, const bus_route &br) >> { >> std::list<bus_stop *>::const_iterator it; >> // note: we're displaying the pointer to permit verification >> // that duplicated pointers are properly restored. >> for(it = br.stops.begin(); it != br.stops.end(); it++){ >> os << '\n' << std::hex << "0x" << *it << std::dec << ' ' << >> **it; >> } >> return os; >> } >> >> ///////////////////////////////////////////////////////////// >> // a bus schedule is a collection of routes each with a starting time >> // >> // Illustrates serialization of STL objects(pair) in a non-intrusive >> way. >> // See definition of operator<< <pair<F, S> >(ar, pair) and others in >> // serialization.hpp >> // >> // illustrates nesting of serializable classes >> // >> // illustrates use of version number to automatically grandfather >> older >> // versions of the same class. >> >> class bus_schedule >> { >> public: >> // note: this structure was made public. because the friend >> declarations >> // didn't seem to work as expected. >> struct trip_info >> { >> template<class Archive> >> void serialize(Archive &ar, const unsigned int file_version) >> { >> // in versions 2 or later >> if(file_version >= 2) >> // read the drivers name >> ar & driver; >> // all versions have the follwing info >> ar & hour & minute; >> } >> >> // starting time >> int hour; >> int minute; >> // only after system shipped was the driver's name added to >> the class >> std::string driver; >> >> trip_info(){} >> trip_info(int _h, int _m, const std::string &_d) : >> hour(_h), minute(_m), driver(_d) >> {} >> }; >> private: >> friend class boost::serialization::access; >> friend std::ostream & operator<<(std::ostream &os, const >> bus_schedule &bs); >> friend std::ostream & operator<<(std::ostream &os, const >> bus_schedule::trip_info &ti); >> std::list<std::pair<trip_info, bus_route *> > schedule; >> template<class Archive> >> void serialize(Archive &ar, const unsigned int version) >> { >> ar & schedule; >> } >> public: >> void append(const std::string &_d, int _h, int _m, bus_route *_br) >> { >> schedule.insert(schedule.end(), std::make_pair(trip_info(_h, >> _m, _d), _br)); >> } >> bus_schedule(){} >> }; >> BOOST_CLASS_VERSION(bus_schedule, 2) >> >> std::ostream & operator<<(std::ostream &os, const >> bus_schedule::trip_info &ti) >> { >> return os << '\n' << ti.hour << ':' << ti.minute << ' ' << >> ti.driver << ' '; >> } >> std::ostream & operator<<(std::ostream &os, const bus_schedule &bs) >> { >> std::list<std::pair<bus_schedule::trip_info, bus_route *> >>> ::const_iterator it; >> for(it = bs.schedule.begin(); it != bs.schedule.end(); it++){ >> os << it->first << *(it->second); >> } >> return os; >> } >> >> void save_schedule(const bus_schedule &s, const char * filename){ >> // make an archive >> std::ofstream ofs(filename); >> boost::archive::text_oarchive oa(ofs); >> oa << s; >> } >> >> //<<<< >> void save_stop(const bus_stop &s, const char * filename){ >> // make an archive >> std::ofstream ofs(filename); >> boost::archive::text_oarchive oa(ofs); >> oa.register_type(static_cast<bus_stop_corner* >(NULL)); >> //ar.template register_type<bus_stop_destination>(); >> oa.register_type(static_cast<bus_stop_destination* >(NULL)); >> >> oa << s; >> } >> //>>>> >> >> void >> restore_schedule(bus_schedule &s, const char * filename) >> { >> // open the archive >> std::ifstream ifs(filename); >> boost::archive::text_iarchive ia(ifs); >> >> // restore the schedule from the archive >> ia >> s; >> } >> >> >> int main(int argc, char *argv[]) >> { >> // make the schedule >> bus_schedule original_schedule; >> >> // fill in the data >> // make a few stops >> bus_stop *bs0 = new bus_stop_corner( >> gps_position(34, 135, 52.560f), >> gps_position(134, 22, 78.30f), >> "24th Street", "10th Avenue" >> ); >> >> //<<<< >> std::string filename1(boost::archive::tmpdir()); >> filename1 += "/demofile1.txt"; >> >> save_stop( *bs0 , filename1.c_str()); >> //>>>> >> bus_stop *bs1 = new bus_stop_corner( >> gps_position(35, 137, 23.456f), >> gps_position(133, 35, 54.12f), >> "State street", "Cathedral Vista Lane" >> ); >> bus_stop *bs2 = new bus_stop_destination( >> gps_position(35, 136, 15.456f), >> gps_position(133, 32, 15.300f), >> "White House" >> ); >> bus_stop *bs3 = new bus_stop_destination( >> gps_position(35, 134, 48.789f), >> gps_position(133, 32, 16.230f), >> "Lincoln Memorial" >> ); >> >> >> // make a routes >> bus_route route0; >> route0.append(bs0); >> route0.append(bs1); >> route0.append(bs2); >> >> // add trips to schedule >> original_schedule.append("bob", 6, 24, &route0); >> original_schedule.append("bob", 9, 57, &route0); >> original_schedule.append("alice", 11, 02, &route0); >> >> // make aother routes >> bus_route route1; >> route1.append(bs3); >> route1.append(bs2); >> route1.append(bs1); >> >> // add trips to schedule >> original_schedule.append("ted", 7, 17, &route1); >> original_schedule.append("ted", 9, 38, &route1); >> original_schedule.append("alice", 11, 47, &route1); >> >> // display the complete schedule >> std::cout << "original schedule"; >> std::cout << original_schedule; >> >> std::string filename(boost::archive::tmpdir()); >> filename += "/demofile.txt"; >> // save the schedule >> save_schedule(original_schedule, filename.c_str()); >> >> // ... some time later >> // make a new schedule >> bus_schedule new_schedule; >> >> restore_schedule(new_schedule, filename.c_str()); >> >> // and display >> std::cout << "\nrestored schedule"; >> std::cout << new_schedule; >> // should be the same as the old one. (except for the pointer >> values) >> >> delete bs0; >> delete bs1; >> delete bs2; >> delete bs3; >> return 0; >> } > > > > > ------------------------------------------------------------------------ > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users

1 0

[statechart] managing large collection of async statemachines.
by Johan Kuijpers 08 Sep '07

08 Sep '07

Hello, I have to instantiate a large collection (1200) of asynchronous statemachines which obviously can not have their own thread of execution. My basic idea was to spawn a collection of threads with 1 scheduler per thread (inline with the tutorial) and then create several processors ie statemachines per scheduler. This seems to work however there's 1 aspect which I can not solve. When queueing an event I have to distribute now the events to the right async statemachine based on a simple id which each event carries. Problem seems the access to the statemachine (I need the id obviously) since I only have a (collection of) processor handles. How can this be done? Kind regards, John.

2 1

polymorphism and boost::shared_ptr
by Brad Ryder 08 Sep '07

08 Sep '07

Greetings, This is my first post to the boost users list and I am a relative new comer to this wonderful template library, so have some mercy on me. I am sure this question has been asked before and I tried to find it via google without any luck. If someone could show me how to make the following polymorphism work so that AddChild of class A will add type B and type C class I would really appreciate it. I don't want to have to typecast in this situation, but I can't see any other way. Please forgive me if this is a basic question, but I am new to some of these concepts. Kind regards Brad typedef boost::shared_ptr<A> shPtrA; typedef boost::shared_ptr<B> shPtrB; typedef boost::shared_ptr<C> shPtrC; class A { void AddChild(shPtrA& child); private: std::vector<shPtrA> m_children; } class B : public A { } class C: public B { } main() { A base; shPtrB spB(new B()); shPtrC spC(new C()); // I dont want to typecast spB or spC A.AddChild( (shPtrA) spB); A.AddChild( (shPtrA) spC); }

3 6

[serialization] additional archive exception reporting
by Robbie Morrison 07 Sep '07

07 Sep '07

Hi all In order to assist my troubleshooting, I wrote a free function called 'extraArchiveWhat' which adds to the sometimes obscure (to me anyway) comments thrown by Boost.Serialization. John Pye-4 wrote: > Vaguely related comment on your problem. I was also recently seeing this > "unregistered void cast" runtime error. As far as I could tell it was a > problem relating to my ordering and placement of "#include > <boost/archive/text_oarchive.hpp> (or ditto iarchive), and "#include > <boost/serialization/export.hpp> as well as calls to BOOST_CLASS_EXPORT. > > It was nothing to do with my use of void_cast_register, which in fact I > don't use anywhere in any of my code. > > So FWIW I think that this error message is not particularly helpful or > well-worded. Here is my client code first (the typedef enables me to switch between text, XML, and platform-specific binary): 8<-------------------------------------- typedef boost::archive::xml_oarchive output_archive_type; const char* cfilename = filename.c_str(); // convert to C-style string ... try { std::ifstream ifs(cfilename, std::ios::binary); if ( !ifs ) // see note below { std::cout << "** ofstream open failed: " << cfilename << std::endl; } input_archive_type ar(ifs); // see above typedef ar & boost::serialization::make_nvp("container", container); } catch (const boost::archive::archive_exception& ae) { std::cout << "** boost::archive load exception" << ": " << __FILE__ << ":" << __LINE__ << ":" << __func__ << ": " << ae.what() << "\n" << " " << extraArchiveWhat(ae.what()) << std::endl; } -------------------------------------->8 Note that C++ stream io operations do not throw exceptions. Each stream keeps its own mask of error bits known as its "io state", accessible via rdstate(). In addition, each stream object can also be treated as a Boolean value representing good (true) or faulty (false). Note too that __FILE__, __LINE__, and __func__ are built-in macros which give the current source file name, line number, and invoked call, respectively. Now the helper function itself: 8<-------------------------------------- std::string // an interpretation based on my experiences extraArchiveWhat (const std::string what) // that is, the string returned by what() { std::string ret = "no local interpretation"; if ( what == "coding error" ) ret = "Boost.Serialization library problem"; else if ( what == "unrecognized XML syntax" ) ret = "name-value-pair name contains illegal chars including whitespace?"; else if ( what == "unregistered class" ) ret = "missing BOOST_CLASS_EXPORT(SubClass) macro?"; else if ( what == "unregistered void cast" ) ret = "missing ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(BaseClass) statement?"; else if ( what == "stream error" ) ret = "asymmetric serialization, including attempt to load empty archive?"; ret = "(" + ret + ")"; // add parentheses return ret; } -------------------------------------->8 Hence a typical message might read: ** boost::archive load exception: main.cpp:101:main: unregistered void cast (missing ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(BaseClass) statement?) Finally, here is a list of possible exceptions copied (with minor tweaks) from the relevant Boost.Serialization headers: // From <boost/archive archive_exception.hpp> // // "programming error" [in Boost.Serialization, that is] // // "unregistered class" : attempt to serialize a pointer // of an an unregistered class // // "invalid signature" : first line of archive does not // contain expected string // // "unsupported version" : archive created with library // version subsequent to this one // // "pointer conflict" : an attempt has been made to // directly serialize an object after having // already serialized the same object through a // pointer -- were this permitted, it the archive // load would result in the creation of extraneous // object // // "incompatible native format" : attempt to read native // binary format on incompatible platform // // "array size too short" : array being loaded doesn't // fit in array allocated // // "stream error": i/o error on stream // // "class name too long" : class name greater than the // maximum permitted -- most likely a corrupted archive // or an attempt to insert a virus via buffer overrun method // // "unregistered void cast" : base - derived relationship not // registered with void_cast_register // // From <boost/archive/basic_xml_archive.hpp> // // "unrecognized XML syntax" : archive doesn't contain // expected data // // "XML start/end tag mismatch" : start/end tag in archive // doesn't match program // // "Invalid XML tag name" : tag name contains // invalid characters cheers, Robbie --- Robbie Morrison PhD student -- policy-oriented energy system simulation Institute for Energy Engineering (IET) Technical University of Berlin (TU-Berlin), Germany [from IMAP client]

1 0

Design for extensibility
by Tim St. Clair 07 Sep '07

07 Sep '07

Folks - I have found that there are several classes in boost, namely the OS constructs (thread, mutex, etc.) do not provide me w/some of the features I'm looking for (and that is ok with me). As an embedded developer I deal with all kinds of operating systems which are not in the main stream, however C++ is very common in the embedded world, and is growing. With that note, I would like to assert the following: - It would be "uber-useful" to design OS constructs, or libraries for that matter, with extensibility in mind. By providing a couple of guidelines, developers could then port to any OS under the sun, or add the features they desire. Instead, I'm left with writing yet another wrapper (ohh joy). Cheers, -Tim

2 2

Boost compiling problem
by Bernard Marnaud 07 Sep '07

07 Sep '07

Hi, I tried to installed the Metaproxy with make on solaris 9, but i have some errors due to Boost library. The YAZ and YAZPP libraries are installed successfully. The Boost compilation (bjam --build-dir=/usr/local/Boost --toolset=gcc stage) gives the following linkage errors: ...failed gcc.link.dll /opt/Boost/boost/bin.v2/libs/program_options/build/gcc-3.4.6/release/threading-multi/libboost_program_options-gcc34-mt-1_34_1.so.1.34.1... ...failed gcc.link.dll /opt/Boost/boost/bin.v2/libs/filesystem/build/gcc-3.4.6/release/threading-multi/libboost_filesystem-gcc34-mt-1_34_1.so.1.34.1... ...failed gcc.link.dll /opt/Boost/boost/bin.v2/libs/graph/build/gcc-3.4.6/release/threading-multi/libboost_graph-gcc34-mt-1_34_1.so.1.34.1... ... You can see below the output of Meataproxy compilation (./configure" '--with-yazpp=/usr/local/src/yazpp-1.0.3/) : ./configure --with-yazpp=/usr/local/src/yazpp-1.0.3/ Make Making all in xml make[1]: Entering directory `/usr/local/src/metaproxy-1.0.11/xml' Making all in schema make[2]: Entering directory `/usr/local/src/metaproxy-1.0.11/xml/schema' make[2]: Nothing to be done for `all'. make[2]: Leaving directory `/usr/local/src/metaproxy-1.0.11/xml/schema' Making all in xslt make[2]: Entering directory `/usr/local/src/metaproxy-1.0.11/xml/xslt' make[2]: Nothing to be done for `all'. make[2]: Leaving directory `/usr/local/src/metaproxy-1.0.11/xml/xslt' make[2]: Entering directory `/usr/local/src/metaproxy-1.0.11/xml' make[2]: Nothing to be done for `all-am'. make[2]: Leaving directory `/usr/local/src/metaproxy-1.0.11/xml' make[1]: Leaving directory `/usr/local/src/metaproxy-1.0.11/xml' Making all in src make[1]: Entering directory `/usr/local/src/metaproxy-1.0.11/src' make all-am make[2]: Entering directory `/usr/local/src/metaproxy-1.0.11/src' /bin/bash ../libtool --tag=CXX --mode=link g++ -pthread -I/usr/local/src/boost_1_34_1 -g -O2 -L/usr/local/src/boost_1_34_1/stage/lib /usr/local/src/yazpp-1.0.3/src/libyazpp.la /usr/local/src/yaz-3.0.10/src/libyaz.la -L/usr/local/lib -R/usr/local/lib -lxslt -lxml2 -lz -lpthread -liconv -lsocket -lnsl -lm -lsocket -lnsl -liconv -lpthread -o metaproxy metaproxy_prog.o libmetaproxy.la -lm -ldl g++ -pthread -I/usr/local/src/boost_1_34_1 -g -O2 -o .libs/metaproxy metaproxy_prog.o -L/usr/local/src/boost_1_34_1/stage/lib -L/sol10/SOURCES/S9/gcc-3.4.6/objdir/sparc-sun-solaris2.9/libstdc++-v3/src -L/sol10/SOURCES/S9/gcc-3.4.6/objdir/sparc-sun-solaris2.9/libstdc++-v3/src/.libs -L/sol10/SOURCES/S9/gcc-3.4.6/objdir/gcc -L/usr/local/lib -L/usr/lib -L/usr/openwin/lib -L/usr/local/ssl/lib -L/usr/local/BerkeleyDB.4.2/lib ./.libs/libmetaproxy.so /usr/local/src/yazpp-1.0.3/src/.libs/libyazpp.so /usr/local/src/yaz-3.0.10/src/.libs/libyaz.so /usr/local/lib/libxslt.so /usr/local/lib/libxml2.so -lz -lsocket -lnsl /usr/local/lib/libiconv.so -lpthread /usr/local/lib/libstdc++.so -lm -ldl -Wl,-R -Wl,/usr/local/lib g++: unrecognized option `-pthread' ld: warning: file /usr/local/lib/libstdc++.so: attempted multiple inclusion of file Undefined first referenced symbol in file boost::program_options::invalid_option_value::invalid_option_value(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)metaproxy_prog.o boost::program_options::positional_options_description::add(char const*, int)metaproxy_prog.o boost::program_options::validation_error::what() constmetaproxy_prog.o boost::detail::condition_impl::notify_all() ./.libs/libmetaproxy.so boost::lock_error::~lock_error() ./.libs/libmetaproxy.so boost::lock_error::lock_error() ./.libs/libmetaproxy.so boost::detail::condition_impl::notify_one() ./.libs/libmetaproxy.so boost::program_options::options_description_easy_init::operator()(char const*, boost::program_options::value_semantic const*, char const*)metaproxy_prog.o boost::program_options::detail::cmdline::run() metaproxy_prog.o boost::xtime_get(boost::xtime*, int)./.libs/libmetaproxy.so typeinfo for boost::program_options::validation_errormetaproxy_prog.o vtable for boost::program_options::validation_errormetaproxy_prog.o boost::program_options::detail::cmdline::set_options_description(boost::program_options::options_description const&)metaproxy_prog.o boost::thread_group::add_thread(boost::thread*) ./.libs/libmetaproxy.so boost::program_options::detail::cmdline::set_positional_options(boost::program_options::positional_options_description const&)metaproxy_prog.o boost::program_options::notify(boost::program_options::variables_map&)metaproxy_prog.o boost::program_options::store(boost::program_options::basic_parsed_options<char> const&, boost::program_options::variables_map&, bool)metaproxy_prog.o boost::program_options::detail::cmdline::cmdline(std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > const&)metaproxy_prog.o boost::mutex::~mutex() ./.libs/libmetaproxy.so boost::mutex::mutex() ./.libs/libmetaproxy.so boost::mutex::do_lock(boost::mutex::cv_state&)./.libs/libmetaproxy.so boost::thread_group::join_all() ./.libs/libmetaproxy.so typeinfo for boost::program_options::value_semantic_codecvt_helper<char>metaproxy_prog.o boost::program_options::to_internal(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)metaproxy_prog.o boost::thread::sleep(boost::xtime const&)./.libs/libmetaproxy.so boost::program_options::options_description::options_description(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned int)metaproxy_prog.o boost::program_options::abstract_variables_map::operator[](std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) constmetaproxy_prog.o boost::program_options::arg metaproxy_prog.o boost::mutex::do_unlock() ./.libs/libmetaproxy.so boost::program_options::value_semantic_codecvt_helper<char>::parse(boost::any&, std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > const&, bool) constmetaproxy_prog.o boost::program_options::operator<<(std::basic_ostream<char, std::char_traits<char> >&, boost::program_options::options_description const&)metaproxy_prog.o boost::program_options::options_description_easy_init::operator()(char const*, char const*)metaproxy_prog.o boost::thread_group::~thread_group()./.libs/libmetaproxy.so boost::thread_group::thread_group() ./.libs/libmetaproxy.so boost::program_options::options_description::add_options() metaproxy_prog.o typeinfo for boost::lock_error ./.libs/libmetaproxy.so boost::detail::condition_impl::~condition_impl()./.libs/libmetaproxy.so boost::detail::condition_impl::condition_impl()./.libs/libmetaproxy.so boost::detail::condition_impl::do_wait(_pthread_mutex*) ./.libs/libmetaproxy.so boost::mutex::do_unlock(boost::mutex::cv_state&)./.libs/libmetaproxy.so boost::program_options::variables_map::variables_map()metaproxy_prog.o boost::thread::thread(boost::function0<void, std::allocator<boost::function_base> > const&)./.libs/libmetaproxy.so boost::mutex::do_lock() ./.libs/libmetaproxy.so vtable for boost::program_options::variables_mapmetaproxy_prog.o boost::program_options::positional_options_description::positional_options_description()metaproxy_prog.o ld: fatal: Symbol referencing errors. No output written to .libs/metaproxy collect2: ld returned 1 exit status make[2]: *** [metaproxy] Error 1 make[2]: Leaving directory `/usr/local/src/metaproxy-1.0.11/src' make[1]: *** [all] Error 2 make[1]: Leaving directory `/usr/local/src/metaproxy-1.0.11/src' make: *** [all-recursive] Error 1 Could you investigate why the compilation doesn't work ? Do you need more informations ? Thans for your cooperation. Best regards. Stéphan. _________________________________________________________________ A la recherche d'un ami d'enfance ? Peut-être est-il dans la liste d'amis de vos amis ! http://spaces.live.com/default.aspx?page=Ed01&ss=True

1 0

Boost way of disabling compiler warnings?
by Christian Henning 07 Sep '07

07 Sep '07

Hi there, I just questioned myself if boost is providing some general way of disabling warning for specific compilers. Something like: BOOST_DISABLE_WARNING( MSVC71, 4675 ); BOOST_DISABLE_WARNING( GCC34, 1234 ); I think that would be cool to have. Regards, Christian

2 1

Boost function question.
by Surya Kiran Gullapalli 07 Sep '07

07 Sep '07

Hello, I'm having the following class structure. template <class T> class TemplatedClass { TemplatedClass () { member = shared_ptr<T> (CreateA()) ; } private: shared_ptr<T> member ; operator->() { return T.get() ; } } ; class BasePlugin { virtual void foo (void) = 0 ; } class DerivedPlugin_A : public BasePlugin { virtual void foo (void) { cout << "FOO in derived A" << endl ;} } ; DerivedPlugin_A* CreateA () { return new DerivedPlugin_A ; } TemplatedClass <BasePlugin> t ; t->foo() ; How do i write a boost::function wrapper for t->foo() ; Please help. Thanks in advance, Surya

3 5

[Boost.Build] installation problem bis
by david shaw 06 Sep '07

06 Sep '07

Hi, ok, I've added new lines to the email: I go there http://www.boost.org/doc/html/jam/building.html I do:C:\Documents and Settings\src\boost\tools\jam\src>build mingw --debug (like explained) A new folder named bin.ntx86.debug is added after I go there http://www.boost.org/doc/html/bbv2/installation.html : 1:(done) 2:I do:C:\Documents and Settings\src\boost\tools\build\v2> bjam --version Instead of seing:Boost.Build V2 (Milestone 11)Boost.Jam 03.1.14 I see:syntax error at EOFBoost.Build V2 (Milestone 11)Boost.Jam 03.1.14 3:I open the user-config.jam file (like explained) and I modify the file, the modification is the following: import toolset : using gcc ; # GCC configuration # Configure gcc (default version) using gcc : : "C:\mingw\bin\g++" ; 4:I copy bjam.exe from C:\Documents and Settings\src\boost\tools\build\v2 to C:\Documents and Settings\src\boost\tools\build\v2\example\hello and I run bjam (like explained): C:\Documents and Settings\src\boost\tools\build\v2\example\hello>bjam I get the following message: C:\Documents and Settings\src\boost\tools\build\v2\kernel\modules.jam:280 :in modules.importIMPORT error:rule gcc unknown in module "toolset." ... ...... ... Where is my error(4)? Thanks, David _________________________________________________________________ Créez un blog Messenger pour partager facilement toutes vos photos de vacances ! http://www.windowslive.fr/spaces/default.asp

2 4

Question about pool.
by 蹬三轮的 06 Sep '07

06 Sep '07

We use boost pool in our project and we found boost's pool may occupy too much memory. Say, if we need a block of memory which size is 1317B, boost's pool will allocate a truck of memory 5268B on a 32bits platform, leave 3951 bytes unused (it get worse on 64bits platform). I don't think it is necessary to allocate 5268B, for the sake of performance, only 1320B is enough for align. It should be resovled because pool is so important to many large application.

2 1

Creating graph type at runtime
by Abhishek V 06 Sep '07

06 Sep '07

Hi Currently i m creating adjacency_list in this format . typedef adjacency_list < vecS, vecS, undirectedS, property < vertex_name_t, std::string >, property < edge_name_t, std::string > > Graph; Graph g; Now user will decide whether the graph is directed or undirected and accordingly i will create the adjancency_list. undirectedS or directedS . Is there any representation which can help me out in this case or suggest me a way by which this can be done.. Thanks Abhishek Vyas Tata Consultancy Services Mailto: abhishek.v(a)tcs.com Website: http://www.tcs.com ____________________________________________ Experience certainty. IT Services Business Solutions Outsourcing ____________________________________________ =====-----=====-----===== Notice: The information contained in this e-mail message and/or attachments to it may contain confidential or privileged information. If you are not the intended recipient, any dissemination, use, review, distribution, printing or copying of the information contained in this e-mail message and/or attachments to it are strictly prohibited. If you have received this communication in error, please notify us by reply e-mail or telephone and immediately and permanently delete the message and any attachments. Thank you

1 0

Want to calculate different parameters for a graph
by Abhishek V 06 Sep '07

06 Sep '07

Hi I want to calculate the center, radius,diameter,rank,nullity,girth,circumference for a graph. I have created an adjancency list with the help of boost. Is there any function or components avaliable in BGL which can give me all or any of these parameters. Thanks Abhishek Vyas Tata Consultancy Services Mailto: abhishek.v(a)tcs.com Website: http://www.tcs.com ____________________________________________ Experience certainty. IT Services Business Solutions Outsourcing ____________________________________________ =====-----=====-----===== Notice: The information contained in this e-mail message and/or attachments to it may contain confidential or privileged information. If you are not the intended recipient, any dissemination, use, review, distribution, printing or copying of the information contained in this e-mail message and/or attachments to it are strictly prohibited. If you have received this communication in error, please notify us by reply e-mail or telephone and immediately and permanently delete the message and any attachments. Thank you

1 0

[xpressive] CVS: Spurious warnings on #include <boost/xpressive/xpressive.hpp>
by Bryan Donlan 06 Sep '07

06 Sep '07

When building with -W -Wall, including <boost/xpressive/xpressive.hpp> produces a number of spurious warnings. GCC version: gcc version 4.1.3 20070831 (prerelease) (Ubuntu 4.1.2-16ubuntu1) Boost version: CVS (regression from 1.34.1) --- test program (build with -W -Wall) --- #include <boost/xpressive/xpressive.hpp> int main() { return 0; } --- end --- --- warning output --- bcvs/boost/boost/xpressive/regex_primitives.hpp:142: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::epsilon_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:149: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::epsilon_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:276: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_bos_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:287: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_eos_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:295: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_bol_placeholder>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:303: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_eol_placeholder>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:311: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_word_placeholder<boost::xpressive::detail::word_begin> >, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:319: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_word_placeholder<boost::xpressive::detail::word_end> >, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:329: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::assert_word_placeholder<boost::xpressive::detail::word_boundary<true> > >, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:377: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::logical_newline_placeholder>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:386: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::any_matcher>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:395: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::self_placeholder>, 0l>::arg0' bcvs/boost/boost/xpressive/regex_primitives.hpp:412: warning: missing initializer for member 'boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::args0<boost::xpressive::detail::set_initializer>, 0l>::arg0' --- end output ---

3 5

(newbie) Cannot find: "norm_inf_index" in the UBLAS lib
by Jim.Zhang＠ubs.com 06 Sep '07

06 Sep '07

Hi, Got a problem using UBLAS. On Vector operations, "norm_inf" works fine, however "norm_inf_index" does not work, "norm_inf_index": identifier not found. I have included the following headers: #include <boost\numeric\ublas\matrix.hpp> #include <boost\numeric\ublas\vector.hpp> #include <boost\numeric\ublas\io.hpp> #include "boost/shared_ptr.hpp" #include "boost/tuple/tuple.hpp" #include <boost/numeric/ublas/matrix_proxy.hpp> Am I missing some specific header file? Does anyone else ever have the similar problem? Thank you for your attention. Visit our website at http://www.ubs.com This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your system. E-mails are not encrypted and cannot be guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. The sender therefore does not accept liability for any errors or omissions in the contents of this message which arise as a result of e-mail transmission. If verification is required please request a hard-copy version. This message is provided for informational purposes and should not be construed as a solicitation or offer to buy or sell any securities or related financial instruments. UBS Limited is a company registered in England & Wales under company number 2035362, whose registered office is at 1 Finsbury Avenue, London, EC2M 2PP, United Kingdom. UBS AG (London Branch) is registered as a branch of a foreign company under number BR004507, whose registered office is at 1 Finsbury Avenue, London, EC2M 2PP, United Kingdom. UBS Clearing and Execution Services Limited is a company registered in England & Wales under company number 03123037, whose registered office is at 1 Finsbury Avenue, London, EC2M 2PP, United Kingdom.

1 0

Re: [Boost-users] Boost-users Digest, Vol 1382, Issue 1
by Vial, Florent 06 Sep '07

06 Sep '07

>"C:mingwbingcc n'est pas reconnu en tant que commande interne ou externe, > un programme executable ou un fichier de commandes .." >..... >"...failled gcc.compile.c++ bin\gcc\debug\hello.o... >...skipped <pbin\gcc\debug>hello.exe for lack of<pbin\gcc\debug>hello.o... >...failed updating one target.. >...skipped one target..." >What is the main problem? Looks like a backslash / forward slash problem to me. I guess that you are running this from a cygwin shell, in which backslashes "\" are note recognized, or in your case omitted. Use forward slashes "/" instead and you should be able to have a working "C:/mingw/bin/gcc". HTH, Florent Arnold & Richter Cine Technik GmbH & Co. Betriebs KG Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRA 57918 Personlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRB 54477 Geschaftsfuhrer: Prof. Dr. Dejan Ilic; Franz Kraus; Jens Schafer Beiratsvorsitzender: Prof. Dr. Hans-Jorg Bullinger

1 0

[boost::serialization] Serializing Dynamically Loaded Libraries - "Unregistered Void Cast"
by Jeshua Bratman 06 Sep '07

06 Sep '07

I already sent a message on this topic a few weeks ago, however, my problem has a changed a bit so I decided to post a new message. I've been trying to get Boost serialization working for dynamically loaded shared libraries. Here's my basic structure simplified: 1. base.hpp - includes an abstract base class called base 2. derived.hpp - includes a derived class from base. includes base.hpp. 3. derived.cpp - includes code for derived class and for dynamically loading it 4. main.cpp - includes base.hpp but NOT derived.hpp. dynamically loads instantiates a base * which points to a derived object from derived.so Now in main I want to be able to serialize my pointer to the loaded derived class: base *obj = create_func(); //obj now points to a derived object obj->test(); //when test is run it correctly outputs the message from derived.cpp const base* const to_serialize = obj; std::ofstream ofs("filename"); boost::archive::text_oarchive oa(ofs); try { oa << (to_serialize); } catch(exception &e) { cout << "Exception: " << e.what() << "\n"; } It compiles fine and I got past the "unregisterd class" problem, but now when I try to serialize the pointer an exception is caught: "Unregistered void cast" This appears to be a problem with registering the derived pointer type from the base type when dynamically loaded from a shared library. However, I do register the derived-base relationship as suggested in the documentation. The serialize method in derived.hpp is as follows: template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar.template register_type(static_cast<derived *>(NULL)); //ar & boost::serialization::base_object<base>(*this); ar & data; boost::serialization::void_cast_register( static_cast<derived *>(NULL), static_cast<base *>(NULL) ); } If anyone knows the cause of this and/or a solution I would be very appreciative. I've been working at this for a long time now and I'm almost ready to write my own simple serialization for my specific purpose. Thank you for your help, Jeshua Bratman -- View this message in context: http://www.nabble.com/-boost%3A%3Aserialization--Serializing-Dynamically-Lo… Sent from the Boost - Users mailing list archive at Nabble.com.

4 7

[serialization, ASIO] Assertion when serializing recursive boost::variant type
by Falco Hirschenberger 05 Sep '07

05 Sep '07

Hi, I have defined a recursive variant type like this: --- typedef boost::make_recursive_variant<bool, int, double, std::string, std::vector< boost::recursive_variant_ >, std::map<std::string, boost::recursive_variant_>, TGrey8Image, TRgbImage, TRgbaImage>::type TVType; --- and two containers which can store this type: --- typedef std::vector<TVType> TVector; typedef std::map<std::string, TVType> TMap; --- I wrote a set of unit-tests testing all types of plain and recursive containers and they work as expected. I also tested (de-)serialization to a binary archive and there's also no problem. Then I implemented a Message class which contains such a TVType + some other stuff. Serializing and deserializing also works in the tests. Finally I implemented a client and server with ASIO like the ASIO "serialization" example. First sending the size of the archive and then the data itself. The sending works but when I want to deserialize my message I get the following assertion: --- testSerialization: /usr/include/boost/variant/detail/visitation_impl.hpp:203: typename Visitor::result_type boost::detail::variant::visitation_impl(int, int, Visitor&, VPCV, mpl_::true_, NBF, W*, S*) [with W = mpl_::int_<20>, S = boost::detail::variant::visitation_impl_step<boost::mpl::l_iter<boost::mpl::l_end>, boost::mpl::l_iter<boost::mpl::l_end> >, Visitor = boost::detail::variant::invoke_visitor<boost::detail::variant::direct_assigner<const int> >, VPCV = void*, NBF = boost::variant<boost::detail::variant::recursive_flag<bool>, int, double, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::vector<boost::recursive_variant_, std::allocator<boost::recursive_variant_> >, std::map<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::recursive_variant_, std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::recursive_variant_> > >, CIS::Image2d<unsigned char>, CIS::Image2d<CIS::RGB>, CIS::Image2d<CIS::RGBA>, boost::detail::variant::void_, boost::detail::variant::void_, boost::detail::variant::void_, boost::detail::variant::void_, boost::detail::variant::void_, boost::detail::variant::void_, boost::detail::variant::void_, boost::detail::variant::void_, boost::detail::variant::void_, boost::detail::variant::void_, boost::detail::variant::void_>::has_fallback_type_]: Assertion `false' failed. --- I absolutely don't know what't wrong here the backtrace iss huge but the point in my code where it happens is the line when deserializing the message. When I comment out the TVType payload of the message, it works. I would really appreciate any clue. Greetings, Falco

2 1

[Boost.MathToolKit] compilation problem w/ VC7.1 & Boost 1.34.1
by Marc Viala 05 Sep '07

05 Sep '07

Hello, My request is related to the thread http://thread.gmane.org/gmane.comp.lib.boost.user/28535/focus=28613. After downloading & installing Boost 1.34.1 via the Windows Installer, I've tried to compile the following small code snippet: #include <boost/math/special_functions/erf.hpp> void main() { } But the compilation failed w/ the following errors: C:\Program Files\boost\boost_1_34_1\boost\math\special_functions\log1p.hpp(195) : error C2785: 'tools::promote_args<T>::type boost::math::log1p(T)' et 'double boost::math::log1p(double)' ont des types de retour différents C:\Program Files\boost\boost_1_34_1\boost\math\special_functions\math_fwd.hpp(246) : voir la déclaration de 'boost::math::log1p' C:\Program Files\boost\boost_1_34_1\boost\math\special_functions\log1p.hpp(182) : voir la déclaration de 'boost::math::log1p' C:\Program Files\boost\boost_1_34_1\boost\math\special_functions\log1p.hpp(195) : error C2912: spécialisation explicite ; 'double boost::math::log1p<double>(double)' n'est pas une spécialisation d'un modèle de fonction C:\Program Files\boost\boost_1_34_1\boost\math\special_functions\log1p.hpp(183) : fatal error C1903: impossible de récupérer à partir des erreurs précédentes ; arrêt de la compilation Compilation Conditions: - Windows XP Pro - Boost 1.34.1 w/ Math. Toolkit Headers files (extracted from Vault Directory) - Visual C++ 7.1 SP1: Version 7.1.6030 Does anyone know how to manage Math.ToolKit headers file w/ Boost 1.34.1 and VC++ 7.1.6030? Marc Viala, PhD Directeur Général/Directeur Technique 122 rue de la Roche-de-Lorzier 38430 MOIRANS Tél : +33 (0)4 76 91 37 60 Fax : +33 (0)4 76 35 00 07 www.acticm.com mailto:mviala@acticm.com

1 0

How to calculate arboricity
by Abhishek V 05 Sep '07

05 Sep '07

Hi I want to calculate the number of components(arboricity) in a graph. I have created an adjancency list with the help of boost. Is there any function or components avaliable in BGL which can give me the arboricity value. Thanks Abhishek Vyas Tata Consultancy Services Mailto: abhishek.v(a)tcs.com Website: http://www.tcs.com ____________________________________________ Experience certainty. IT Services Business Solutions Outsourcing ____________________________________________ =====-----=====-----===== Notice: The information contained in this e-mail message and/or attachments to it may contain confidential or privileged information. If you are not the intended recipient, any dissemination, use, review, distribution, printing or copying of the information contained in this e-mail message and/or attachments to it are strictly prohibited. If you have received this communication in error, please notify us by reply e-mail or telephone and immediately and permanently delete the message and any attachments. Thank you

2 1

format and filesystem::ofstream mix problem
by Zdravko Baš 05 Sep '07

05 Sep '07

I have a problem with boost 1.34.1 (filesystem::ofstream and format). Compiler Vc71 and vc80 Is this is a bug or my mistake. Zdravko Code: #include <boost/format.hpp> #include <boost/filesystem/fstream.hpp> #include <boost/filesystem.hpp> void test () { boost::filesystem::ofstream os (boost::filesystem::path ("foo.out")); os << boost::format("%s\n") % "foo.text"; } Vc80 output: c:\projects\boost_test\test.cpp(8) : error C2593: 'operator <<' is ambiguous d:\libs\cpp\boost\1.34.1\boost\boost\filesystem\path.hpp(617): could be 'std::basic_ostream<_Elem,_Traits> &boost::filesystem::operator <<<boost::basic_format<Ch>>(std::basic_ostream<_Elem,_Traits> &,const Path &)' [found using argument-dependent lookup] with [ _Elem=char, _Traits=std::char_traits<char>, Ch=char, Path=boost::basic_format<char> ] d:\libs\cpp\boost\1.34.1\boost\boost\format\free_funcs.hpp(33): or 'std::basic_ostream<_Elem,_Traits> &boost::operator <<<char,std::char_traits<char>,std::allocator<_Ty>>(std::basic_ostream<_Elem,_Traits> &,const boost::basic_format<Ch> &)' [found using argument-dependent lookup] with [ _Elem=char, _Traits=std::char_traits<char>, _Ty=char, Ch=char ] while trying to match the argument list '(boost::filesystem::ofstream, boost::basic_format<Ch>)' with [ Ch=char ]

1 0

program_options: change output format?
by Miles Bader 05 Sep '07

05 Sep '07

Is there a way to change the output format that program_options::options_description uses for operator<<? I don't like the output format it uses by default, and I'd like to use the usual GNU format instead. Alternatively, is there a relatively easy way to iterate over all the entries in an options_description (which can be nested, I gather) in a way that I could print the help output myself? From looking over the interface, it seems that there's not really enough information exposed (via the public interface) to do this -- e.g., the "short name" of an option_description is private, and there doesn't seem to be any way to get access to the "groups" in options_descriptions. Thanks, -Miles -- Would you like fries with that?

2 3

Boost.Test claims Qt leaks memory
by Steve M. Robbins 05 Sep '07

05 Sep '07

Hi, I'd appreciate some advice using the Boost unit testing library with Qt classes. I'm using MSVC 8.0 on windows XP. It appears that simply creating and destroying a QObject allocates some static datastructures which are reported as a memory leak by Boost.Test. I'd like to somehow suppress this "static leak" so that Boost.Test may find real leaks in my code. Consider the following test program #define BOOST_AUTO_TEST_MAIN #include <boost/test/auto_unit_test.hpp> #include <Qt/qobject.h> BOOST_AUTO_TEST_CASE( example ) { BOOST_CHECK_EQUAL( 1, 1 ); QObject obj; } It builds and runs fine, except that memory leaks are detected. My first line of attack is to clean up after Qt somehow. (c.f. http://lists.trolltech.com/qt-interest/2007-08/thread00997-0.html) But failing that, is there some way to have Boost.Test ignore these static allocations? I tried turning off leak detection, allocating and deleting a QObject, then turning leak detection back on. But the leaks are still reported. Any ideas? Thanks, -Steve

2 2

tuple versus struct?
by Graham Reitz 05 Sep '07

05 Sep '07

One of my colleagues has asked me, "why not use a simple struct over a tuple?" Unfortunately, I couldn't give a convincing answer, which means I probably don't understand tuple well enough. What is a good way to respond to this? Then we can identify when it makes better sense to use a struct versus a tuple. Thanks, Graham

5 4

using shared_array in Nd array
by Jeffrey Jiang 04 Sep '07

04 Sep '07

Hi, I am new to boost, and is trying to implement shared_ptr solution to a 2d array of pointers. Eg Character *** characters; characters = new Character**[_info._l ]; for (int i=0; i< _info._l; i++){ characters[i] = new Character* [_info._w]; for( int j=0;j < _info._w; j++){ characters[i][j] = 0; } } This is a sparse array, most of the pointers will be set to 0. As I could not find much information about shared_array on line, I would like to check is there any issue with this implementation. boost::shared_array<boost::shared_array<boost::shared_ptr<Character>>> characterGrid(new boost::shared_array<boost::shared_ptr<Character>>[_info._l ]); for( int i=0;i< _info._l; i++) { characterGrid[i] = boost::shared_array<boost::shared_ptr<Character>>(new boost::shared_ptr<Character>[_info._w]); for( int j=0; j< _info._w; j++) { //is it alright for me to use an empty shared_ptr in this context to init the array? characterGrid[i][j] = boost::shared_ptr<Character>(); } } Thanks. Jeffrey.

2 3

Traversing through a multi_array and accessing the data set...
by Graham Reitz 04 Sep '07

04 Sep '07

How do you access the data in the example below? Thanks much, Graham boost::multi_array<double,2> multi_test; boost::multi_array<double,2>::iterator multi_test_iter; boost::multi_array<double,2>::extent_gen extents; multi_test.resize(extents[2][3]); for (multi_test_iter = multi_test.begin(); multi_test_iter != multi_test.end(); ++multi_test_iter) { // How do you get(set) at the current data set pointed to by multi_test_iter? }

2 2

[Serialization] New user: serializing base class
by Len Berman 04 Sep '07

04 Sep '07

Hi, I am trying to understand the differences between intrusive and non-intrusive style of serialization for derived classes. The classes I want to serialize look like: class Base {} template<class TYPE> class Derived : public Base , public std::vector<TYPE> {} where it is intended that TYPE is a built in C type (int, double, ...) I'm starting by trying to understand the demo.cpp example since that example serializes derived classes. My first goal is to serialize bus_stop_corner and bus_stop_destination directly through the base class. These are serialized through a pointer indirectly when bus_stop_schedule is serialized; however, I've been unable to do this directly. I've gone about it using the pseudo-code in 'Pointers to Objects of Derived Classes'; however, I get the following compilation error: g++ -g demo2.cpp -o demo2 /usr/lib/libboost_serialization.a (I'm using g++ (GCC) 4.1.2 20061115 (prerelease) (Debian 4.1.1-21)) /usr/include/boost/archive/detail/oserializer.hpp: In function $-1òøvoid boost::archive::save(Archive&, T&) [with Archive = boost::archive::text_oarchive, T = bus_stop*]òù: /usr/include/boost/archive/basic_text_oarchive.hpp:78: instantiated from $-1òøvoid boost::archive::basic_text_oarchive<Archive>::save_override(T&, int) [with T = bus_stop*, Archive = boost::archive::text_oarchive]òù /usr/include/boost/archive/detail/interface_oarchive.hpp:78: instantiated from $-1òøArchive& boost::archive::detail::interface_oarchive<Archive>::operator<<(T&) [with T = bus_stop*, Archive = boost::archive::text_oarchive]òù demo2.cpp:164: instantiated from here /usr/include/boost/archive/detail/oserializer.hpp:567: error: invalid application of $-1òøsizeofòù to incomplete type òøboost::STATIC_ASSERTION_FAILURE<false>òù I've also tried by taking the full demo.cpp, and creating a function, save_stop, modeled after save_schedule. This compiles but saves only the base class. This larger piece of code is below, after ++++++++++++++++++. Differences from demo.cpp are marked with //<<<< Obviously, I'm missing something; hopefully, something simple. Any help greatly appreciated. Thanks. --Len /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8 // demo.cpp // // (C) Copyright 2002-4 Robert Ramey - http://www.rrsd.com . // Use, modification and distribution is subject to the Boost Software // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) #include <iomanip> #include <iostream> #include <fstream> #include <string> #include <boost/archive/tmpdir.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/serialization/base_object.hpp> #include <boost/serialization/utility.hpp> #include <boost/serialization/list.hpp> class gps_position { friend std::ostream & operator<<(std::ostream &os, const gps_position &gp); friend class boost::serialization::access; int degrees; int minutes; float seconds; template<class Archive> void serialize(Archive & ar, const unsigned int /* file_version */){ ar & degrees & minutes & seconds; } public: // every serializable class needs a constructor gps_position(){}; gps_position(int _d, int _m, float _s) : degrees(_d), minutes(_m), seconds(_s) {} }; std::ostream & operator<<(std::ostream &os, const gps_position &gp) { return os << ' ' << gp.degrees << (unsigned char)186 << gp.minutes << '\'' << gp.seconds << '"'; } ///////////////////////////////////////////////////////////// // One bus stop // // illustrates serialization of serializable members // class bus_stop_corner; class bus_stop_destination; class bus_stop { friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream &os, const bus_stop &gp); virtual std::string description() const = 0; gps_position latitude; gps_position longitude; template<class Archive> void serialize(Archive &ar, const unsigned int version) { // register all derived classes. ar.register_type(static_cast<bus_stop_corner>(NULL)); ar.register_type(static_cast<bus_stop_destination>(NULL)); ar & latitude; ar & longitude; } protected: bus_stop(const gps_position & _lat, const gps_position & _long) : latitude(_lat), longitude(_long) {} public: bus_stop(){} // virtual void serialize(std::ostream &ar, const unsigned int file_version) = 0; virtual ~bus_stop(){} }; BOOST_IS_ABSTRACT(bus_stop) std::ostream & operator<<(std::ostream &os, const bus_stop &bs) { return os << bs.latitude << bs.longitude << ' ' << bs.description(); } ///////////////////////////////////////////////////////////// // Several kinds of bus stops // // illustrates serialization of derived types // class bus_stop_corner : public bus_stop { friend class boost::serialization::access; std::string street1; std::string street2; virtual std::string description() const { return street1 + " and " + street2; } template<class Archive> void serialize(Archive &ar, const unsigned int version) { // save/load base class information ar & boost::serialization::base_object<bus_stop>(*this); ar & street1 & street2; } public: bus_stop_corner(){} // virtual void serialize(std::ostream &ar, const unsigned int file_version){ // ar << "bus_stop_corner"; // }; bus_stop_corner(const gps_position & _lat, const gps_position & _long, const std::string & _s1, const std::string & _s2 ) : bus_stop(_lat, _long), street1(_s1), street2(_s2) { } }; class bus_stop_destination : public bus_stop { friend class boost::serialization::access; std::string name; virtual std::string description() const { return name; } template<class Archive> void serialize(Archive &ar, const unsigned int version) { description(); ar & boost::serialization::base_object<bus_stop>(*this) & name; } public: bus_stop_destination(){} // virtual void serialize(std::ostream &ar, const unsigned int file_version){ // ar << "bus_stop_destination"; // }; bus_stop_destination( const gps_position & _lat, const gps_position & _long, const std::string & _name ) : bus_stop(_lat, _long), name(_name) { } }; int main(int argc, char *argv[]) { // fill in the data // make a few stops bus_stop_corner *bsc0; bus_stop *bs0 = bsc0 = new bus_stop_corner( gps_position(34, 135, 52.560f), gps_position(134, 22, 78.30f), "24th Street", "10th Avenue" ); std::ofstream ofs("demofile1.txt"); boost::archive::text_oarchive oa(ofs); oa << bs0; } ++++++++++++++++++++++++++++++++++++++ /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8 // demo.cpp // // (C) Copyright 2002-4 Robert Ramey - http://www.rrsd.com . // Use, modification and distribution is subject to the Boost Software // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) #include <iomanip> #include <iostream> #include <fstream> #include <string> #include <boost/archive/tmpdir.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/serialization/base_object.hpp> #include <boost/serialization/utility.hpp> #include <boost/serialization/list.hpp> ///////////////////////////////////////////////////////////// // The intent of this program is to serve as a tutorial for // users of the serialization package. An attempt has been made // to illustrate most of the facilities of the package. // // The intent is to create an example suffciently complete to // illustrate the usage and utility of the package while // including a minimum of other code. // // This illustration models the bus system of a small city. // This includes, multiple bus stops, bus routes and schedules. // There are different kinds of stops. Bus stops in general will // will appear on multiple routes. A schedule will include // muliple trips on the same route. ///////////////////////////////////////////////////////////// // gps coordinate // // llustrates serialization for a simple type // class gps_position { friend std::ostream & operator<<(std::ostream &os, const gps_position &gp); friend class boost::serialization::access; int degrees; int minutes; float seconds; template<class Archive> void serialize(Archive & ar, const unsigned int /* file_version */){ ar & degrees & minutes & seconds; } public: // every serializable class needs a constructor gps_position(){}; gps_position(int _d, int _m, float _s) : degrees(_d), minutes(_m), seconds(_s) {} }; std::ostream & operator<<(std::ostream &os, const gps_position &gp) { return os << ' ' << gp.degrees << (unsigned char)186 << gp.minutes << '\'' << gp.seconds << '"'; } ///////////////////////////////////////////////////////////// // One bus stop // // illustrates serialization of serializable members // class bus_stop { friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream &os, const bus_stop &gp); virtual std::string description() const = 0; gps_position latitude; gps_position longitude; template<class Archive> void serialize(Archive &ar, const unsigned int version) { ar & latitude; ar & longitude; } protected: bus_stop(const gps_position & _lat, const gps_position & _long) : latitude(_lat), longitude(_long) {} public: bus_stop(){} virtual ~bus_stop(){} }; BOOST_IS_ABSTRACT(bus_stop) std::ostream & operator<<(std::ostream &os, const bus_stop &bs) { return os << bs.latitude << bs.longitude << ' ' << bs.description(); } ///////////////////////////////////////////////////////////// // Several kinds of bus stops // // illustrates serialization of derived types // class bus_stop_corner : public bus_stop { friend class boost::serialization::access; std::string street1; std::string street2; virtual std::string description() const { return street1 + " and " + street2; } template<class Archive> void serialize(Archive &ar, const unsigned int version) { // save/load base class information ar & boost::serialization::base_object<bus_stop>(*this); ar & street1 & street2; } public: bus_stop_corner(){} bus_stop_corner(const gps_position & _lat, const gps_position & _long, const std::string & _s1, const std::string & _s2 ) : bus_stop(_lat, _long), street1(_s1), street2(_s2) { } }; class bus_stop_destination : public bus_stop { friend class boost::serialization::access; std::string name; virtual std::string description() const { return name; } template<class Archive> void serialize(Archive &ar, const unsigned int version) { description(); ar & boost::serialization::base_object<bus_stop>(*this) & name; } public: bus_stop_destination(){} bus_stop_destination( const gps_position & _lat, const gps_position & _long, const std::string & _name ) : bus_stop(_lat, _long), name(_name) { } }; ///////////////////////////////////////////////////////////// // a bus route is a collection of bus stops // // illustrates serialization of STL collection templates. // // illustrates serialzation of polymorphic pointer (bus stop *); // // illustrates storage and recovery of shared pointers is correct // and efficient. That is objects pointed to by more than one // pointer are stored only once. In such cases only one such // object is restored and pointers are restored to point to it // class bus_route { friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream &os, const bus_route &br); typedef bus_stop * bus_stop_pointer; std::list<bus_stop_pointer> stops; template<class Archive> void serialize(Archive &ar, const unsigned int version) { // in this program, these classes are never serialized directly but rather // through a pointer to the base class bus_stop. So we need a way to be // sure that the archive contains information about these derived classes. //ar.template register_type<bus_stop_corner>(); ar.register_type(static_cast<bus_stop_corner *>(NULL)); //ar.template register_type<bus_stop_destination>(); ar.register_type(static_cast<bus_stop_destination *>(NULL)); // serialization of stl collections is already defined // in the header ar & stops; } public: bus_route(){} void append(bus_stop *_bs) { stops.insert(stops.end(), _bs); } }; std::ostream & operator<<(std::ostream &os, const bus_route &br) { std::list<bus_stop *>::const_iterator it; // note: we're displaying the pointer to permit verification // that duplicated pointers are properly restored. for(it = br.stops.begin(); it != br.stops.end(); it++){ os << '\n' << std::hex << "0x" << *it << std::dec << ' ' << **it; } return os; } ///////////////////////////////////////////////////////////// // a bus schedule is a collection of routes each with a starting time // // Illustrates serialization of STL objects(pair) in a non-intrusive way. // See definition of operator<< <pair<F, S> >(ar, pair) and others in // serialization.hpp // // illustrates nesting of serializable classes // // illustrates use of version number to automatically grandfather older // versions of the same class. class bus_schedule { public: // note: this structure was made public. because the friend declarations // didn't seem to work as expected. struct trip_info { template<class Archive> void serialize(Archive &ar, const unsigned int file_version) { // in versions 2 or later if(file_version >= 2) // read the drivers name ar & driver; // all versions have the follwing info ar & hour & minute; } // starting time int hour; int minute; // only after system shipped was the driver's name added to the class std::string driver; trip_info(){} trip_info(int _h, int _m, const std::string &_d) : hour(_h), minute(_m), driver(_d) {} }; private: friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream &os, const bus_schedule &bs); friend std::ostream & operator<<(std::ostream &os, const bus_schedule::trip_info &ti); std::list<std::pair<trip_info, bus_route *> > schedule; template<class Archive> void serialize(Archive &ar, const unsigned int version) { ar & schedule; } public: void append(const std::string &_d, int _h, int _m, bus_route *_br) { schedule.insert(schedule.end(), std::make_pair(trip_info(_h, _m, _d), _br)); } bus_schedule(){} }; BOOST_CLASS_VERSION(bus_schedule, 2) std::ostream & operator<<(std::ostream &os, const bus_schedule::trip_info &ti) { return os << '\n' << ti.hour << ':' << ti.minute << ' ' << ti.driver << ' '; } std::ostream & operator<<(std::ostream &os, const bus_schedule &bs) { std::list<std::pair<bus_schedule::trip_info, bus_route *> >::const_iterator it; for(it = bs.schedule.begin(); it != bs.schedule.end(); it++){ os << it->first << *(it->second); } return os; } void save_schedule(const bus_schedule &s, const char * filename){ // make an archive std::ofstream ofs(filename); boost::archive::text_oarchive oa(ofs); oa << s; } //<<<< void save_stop(const bus_stop &s, const char * filename){ // make an archive std::ofstream ofs(filename); boost::archive::text_oarchive oa(ofs); oa.register_type(static_cast<bus_stop_corner* >(NULL)); //ar.template register_type<bus_stop_destination>(); oa.register_type(static_cast<bus_stop_destination* >(NULL)); oa << s; } //>>>> void restore_schedule(bus_schedule &s, const char * filename) { // open the archive std::ifstream ifs(filename); boost::archive::text_iarchive ia(ifs); // restore the schedule from the archive ia >> s; } int main(int argc, char *argv[]) { // make the schedule bus_schedule original_schedule; // fill in the data // make a few stops bus_stop *bs0 = new bus_stop_corner( gps_position(34, 135, 52.560f), gps_position(134, 22, 78.30f), "24th Street", "10th Avenue" ); //<<<< std::string filename1(boost::archive::tmpdir()); filename1 += "/demofile1.txt"; save_stop( *bs0 , filename1.c_str()); //>>>> bus_stop *bs1 = new bus_stop_corner( gps_position(35, 137, 23.456f), gps_position(133, 35, 54.12f), "State street", "Cathedral Vista Lane" ); bus_stop *bs2 = new bus_stop_destination( gps_position(35, 136, 15.456f), gps_position(133, 32, 15.300f), "White House" ); bus_stop *bs3 = new bus_stop_destination( gps_position(35, 134, 48.789f), gps_position(133, 32, 16.230f), "Lincoln Memorial" ); // make a routes bus_route route0; route0.append(bs0); route0.append(bs1); route0.append(bs2); // add trips to schedule original_schedule.append("bob", 6, 24, &route0); original_schedule.append("bob", 9, 57, &route0); original_schedule.append("alice", 11, 02, &route0); // make aother routes bus_route route1; route1.append(bs3); route1.append(bs2); route1.append(bs1); // add trips to schedule original_schedule.append("ted", 7, 17, &route1); original_schedule.append("ted", 9, 38, &route1); original_schedule.append("alice", 11, 47, &route1); // display the complete schedule std::cout << "original schedule"; std::cout << original_schedule; std::string filename(boost::archive::tmpdir()); filename += "/demofile.txt"; // save the schedule save_schedule(original_schedule, filename.c_str()); // ... some time later // make a new schedule bus_schedule new_schedule; restore_schedule(new_schedule, filename.c_str()); // and display std::cout << "\nrestored schedule"; std::cout << new_schedule; // should be the same as the old one. (except for the pointer values) delete bs0; delete bs1; delete bs2; delete bs3; return 0; }

2 1

[Boost.Build] installation problem
by david shaw 04 Sep '07

04 Sep '07

Hi,I go there http://www.boost.org/doc/html/jam/building.htmlI do:C:\Documents and Settings\src\boost\tools\jam\src>build mingw --debug (like explained)A new folder named bin.ntx86.debug is added after I go there http://www.boost.org/doc/html/bbv2/installation.html 1:(done) 2:I do:C:\Documents and Settings\src\boost\tools\build\v2> bjam --versionInstead of seing:Boost.Build V2 (Milestone 11)Boost.Jam 03.1.14 I see:syntax error at EOFBoost.Build V2 (Milestone 11)Boost.Jam 03.1.14 3:I open the user-config.jam file (like explained) and I modify the file, the modification is the following: import toolset : using gcc ;# GCC configuration# Configure gcc (default version) using gcc : : "C:\mingw\bin\g++" ; 4:I copy bjam.exe from C:\Documents and Settings\src\boost\tools\build\v2 to C:\Documents and Settings\src\boost\tools\build\v2\example\hello and I run bjam (like explained):C:\Documents and Settings\src\boost\tools\build\v2\example\hello>bjam I get :C:\Documents and Settings\src\boost\tools\build\v2\kernel\modules.jam:280 :in modules.importIMPORT error:rule gcc unknown in module "toolset."... ...... ... Where is my error(4)? Thanks, David _________________________________________________________________ Téléchargez gratuitement l'économiseur d'écran Les Simson Le film ! http://specials.divertissements.fr.msn.com/lessimpsonlefilm/economiseur.aspx

2 1

Using stringtok with multiarray
by Abhishek V 04 Sep '07

04 Sep '07

Hi My overall goal is to read a csv file and then create a graph out of this. Which can be provided as an input to the boost graph library.For creating vertex set i have used vector and for edges i m making use of multiarray. The sample code snippet is provided below.. (This is not the actual code) /* vector<string> vect; string str="L1,L2,L3,L4,L5"; string str1="L1,0,0,0,0"; string str2="L2,0,0,0,0"; boost::stringtok(vect,str,","); typedef boost::multi_array<string,2> my_array; typedef my_array::index index; int size =vect.size(); my_array A1(boost::extents[size][size]); int i=0; for(index jt=0;jt!=size;jt++) { boost::stringtok(A1[0][jt],str1,","); } The one in Bold gives an error message.. c:\srlgrp\boostlib\boost_1_34_0\boost_1_34_0\boost\pending\stringtok.hpp(103) : error C2039: 'push_back' : is not a member of 'multi_array<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,2,class std::allocator <class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > >' Please help regarding this. Also let me know if this is the best way to perform the task or something else will be better... Abhishek Vyas Tata Consultancy Services Mailto: abhishek.v(a)tcs.com Website: http://www.tcs.com ____________________________________________ Experience certainty. IT Services Business Solutions Outsourcing ____________________________________________ =====-----=====-----===== Notice: The information contained in this e-mail message and/or attachments to it may contain confidential or privileged information. If you are not the intended recipient, any dissemination, use, review, distribution, printing or copying of the information contained in this e-mail message and/or attachments to it are strictly prohibited. If you have received this communication in error, please notify us by reply e-mail or telephone and immediately and permanently delete the message and any attachments. Thank you

4 9

BUG/PATCH: Spurious warning in boost::xpressive::detail::enable_reference_tracking
by Bryan Donlan 04 Sep '07

04 Sep '07

Creating a static xpressive regex object referencing statically another regex object causes a spurious (and often extremely long) warning when gcc's -W and -Wall flags are in use. GCC version: version 4.1.3 20070831 (prerelease) (Ubuntu 4.1.2-16ubuntu1) boost version: 1.34.0 and 1.34.1 To demonstrate this bug, build the following on -W -Wall: --- boostbug.cc --- #include <boost/xpressive/xpressive.hpp> int main() { boost::xpressive::sregex r1 = boost::xpressive::digit; boost::xpressive::sregex r2 = *r1; return 0; } --- end boostbug.cc --- The warning output is as follows: /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp: In copy constructor 'boost::xpressive::detail::enable_reference_tracking<Derived>::enable_reference_tracking(const boost::xpressive::detail::enable_reference_tracking<Derived>&) [with Derived = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >]': /usr/include/boost/xpressive/detail/core/regex_impl.hpp:63: instantiated from 'boost::xpressive::detail::regex_impl<BidiIter>::regex_impl(const boost::xpressive::detail::regex_impl<BidiIter>&) [with BidiIter = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >]' /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp:173: instantiated from 'void boost::xpressive::detail::enable_reference_tracking<Derived>::tracking_clear() [with Derived = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >]' /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp:395: instantiated from 'boost::xpressive::detail::tracking_ptr<Type>& boost::xpressive::detail::tracking_ptr<Type>::operator=(const boost::xpressive::detail::tracking_ptr<Type>&) [with Type = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >]' /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp:373: instantiated from 'boost::xpressive::detail::tracking_ptr<Type>::tracking_ptr(const boost::xpressive::detail::tracking_ptr<Type>&) [with Type = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >]' /usr/include/boost/xpressive/basic_regex.hpp:53: instantiated from 'boost::xpressive::basic_regex<BidiIter>::basic_regex(const boost::xpressive::basic_regex<BidiIter>&) [with BidiIter = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >]' boostbug.cc:4: instantiated from here /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp:205: warning: base class 'class boost::enable_shared_from_this<boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >' should be explicitly initialized in the copy constructor I've attached a trivial patch (against 1.34.0; applies cleanly to 1.34.1) to silence this warning.

2 1

Do we like the same books?
by abir basak 04 Sep '07

04 Sep '07

I just joined Shelfari to connect with other book lovers. Come see the books I love and see if we have any in common. Then pick my next book so I can keep on reading. Click below to join my group of friends on Shelfari! http://www.shelfari.com/Register.aspx?ActivityId=7696512&InvitationCode=7f8… abir basak Shelfari is a free site that lets you share book ratings and reviews with friends and meet people who have similar tastes in books. It also lets you build an online bookshelf, join book clubs, and get good book recommendations from friends. You should check it out. -------- You have received this email because abir basak (abirbasak(a)gmail.com) directly invited you to join his/her community on Shelfari. It is against Shelfari's policies to invite people who you don't know directly. Follow this link (http://www.shelfari.com/actions/emailoptout.aspx?email=boost-users@lists.bo…) to prevent future invitations to this address. If you believe you do not know this person, you may view (http://www.shelfari.com/abirbasak) his/her Shelfari page or report him/her in our feedback (http://www.shelfari.com/Feedback.aspx) section. Shelfari, 616 1st Ave #300, Seattle, WA 98104

1 0

boost, LD_PRELOAD and segfault
by Lorenzo Cavallaro 03 Sep '07

03 Sep '07

Hi all, I'm experiencing something very weird. I'm developing a shared object written in C++ and linked against libboost-serialization-gcc41.so. This dynamic library is preloaded before launching a test program (proftpd). As soon as a try to log into the ftp server using a non-anonymous user, I get a segfault from the child the was handling the client connection. Of course, the same code, without libboost-serialization-gcc41.so linked against is perfectly working. I also removed any serialize method so basically only the libboost header file are included with the library linked as well. Do you guys have any idea of what's going on? Libboost version 1.34.1, gcc version 4.1. I'm going to build the gcc-3.4 version of the library and I'll turn debugging on. TIA, bye Lorenzo PS: of course I tried to debug but what I got was pretty useless. No clue. For instance, strace showed a syscall (gettimeofday) is successfully invoked before the segfault. -- Lorenzo `Gigi Sullivan' Cavallaro <sullivan(a)security.dico.unimi.it> GPG key at http://security.dico.unimi.it/~sullivan/sullivan.asc Until I loved, life had no beauty; I did not know I lived until I had loved. (Theodor Korner) See the reality in your eyes, when the hate makes you blind. (A.H.X)

2 2

[serialization] "unregistered void cast" error -- what does it mean?
by John Pye 03 Sep '07

03 Sep '07

Hi all I have been getting an 'unregistered void cast' *runtime* error message following some apparently unrelated changes to my code. Can anyone possibly clarify the cases when it is necessary to use "void_cast_register" with Boost::Serialization? I think that the error is coming from attempts to serialize this class: class MirrorBundleIndexed : public std::map<MeshIndex, boost::shared_ptr<Mirror> > , public Object { public: typedef boost::shared_ptr<Mirror> valuetype; typedef std::map<MeshIndex,valuetype> container; typedef container::iterator iterator; typedef container::const_iterator const_iterator; ... private: friend class boost::serialization::access; template<class Archive> OPTX_LOCAL void serialize(Archive & ar, const unsigned int version){ ar & boost::serialization::base_object<Object>(*this); ar & boost::serialization::base_object<container>(*this); } }; Cheers JP

2 1

[boost::thread] Problems with condition objects
by Rene Tarantino 03 Sep '07

03 Sep '07

Hi: I'm having a bit of trouble with the implementation of the monitor pattern by means of using mutex and condition classes. I have a scheduler thread and a group of worker threads and the scheduling algorithm waits until some worker notifies that it has done the job. It seems that the call to condition::notify_one() must be in a specific order because if the worker calls notify_one before the scheduler arrives to the waiting line it behaves as if the condition object has lost the previous call to notify_one. Is this behavior the one we must expect? and, if so, can any one share a workaround. Thanks in advance. René

2 1

[regex] Why pattern anchored at buffer end ($) also match for (\x0c)FF, (\x0d)CR
by Chandan Nilange 03 Sep '07

03 Sep '07

Hello, As per PCRE /m modifier $ will match the pattern before any newline. However boost_regex gives back matches before formfeed(\x0c) & CarriagReturn(\x0d) Same is observed for ^ i.e match after newline. Please could anybody let me know what is the right pcre behaviour? I have attached the example for demonstration of the case, using boost_regex Regards, Chandan --------------------------------- Park yourself in front of a world of choices in alternative vehicles. Visit the Yahoo! Auto Green Center. #include <iostream> #include <string> #include "/home/ChandanNilange/work/boost/boost_1_34_0/boost/regex.hpp" // Boost.Regex lib using namespace std; int main( ) { std::string s,sre; //regular expression sre="\x30$"; //Matching string s="\x01\x30\x02\x31\x03\x32\x04\x33\x05\x34\x06\x35\x07\x36\x08\x37\x09\x30\x0a\x39\x0b\x30\x0c\x30\x0d\x3c\x0e\x3d\x0f"; boost::regex re; re.assign(sre, boost::regex_constants::perl); std::string::const_iterator start, end; start = s.begin(); end = s.end(); boost::sregex_iterator it(start, end, re); boost::sregex_iterator it_end; for( ; it != it_end; it++) { cout << "Found Pattern:start:" << std::string((*it)[0].first, (*it)[0].second) << ":end:\n" << "Pattern starts at :" << (*it)[0].first - s.begin() << "\nPattern ends at: " << ((*it)[0].second - 1) - s.begin() << "\nPattern length:" << (*it)[0].length() << endl; } } /************************** Results: Found Pattern:start:0:end: Pattern starts at :17 Pattern ends at: 17 Pattern length:1 Found Pattern:start:0:end: Pattern starts at :21 Pattern ends at: 21 Pattern length:1 Found Pattern:start:0:end: Pattern starts at :23 Pattern ends at: 23 Pattern length:1 ****************************/

3 4

[Filesystem] Native Pathname Format
by Edward Diener 03 Sep '07

03 Sep '07

I can not determine from the Filesystem documentation, nor the reference documentation which comes with it, what is the acceptable syntax for the native pathname format. It appears one must start the native pathname format with //: in order for it to be recognized, but I can not tell from what appears to me to be very confusing documentation whether this is so for the Boost Fileystem implementation. This would mean, let's say under Windows, that "c:\afile" would not be recognized but that "//:c:\afile" would be recognized, as far as I can make out from the documentation. It sure is confusing IMO. Can anybody clarify how this works for Filesystem and/or where there is a clear explanation of how it works in the documentation ?

2 3

boost::timer elapsed_max() is too small
by Peng Yu 03 Sep '07

03 Sep '07

Hi, I want to use boost timer to measure my program runtime. Unfortunately, the maximum elapsed time that it can give is only about two thousand seconds. I'm wondering if there is any way to increase this limit? Thanks, Peng $ cat main.cc #include <boost/timer.hpp> #include <iostream> int main() { boost::timer this_timer; std::cout << this_timer.elapsed_max() << " sec" << std::endl; } $ ./main-g.exe 2147.48 sec

1 0

boost::any typeid and different modules
by Gernot Vormayr 02 Sep '07

02 Sep '07

Hi! I have some problems using boost::any in different modules that get loaded with libdl. If i store an int in the boost::any it works like a charm - but when i use a std::string then the boost::any (holding a std::string) isn't any_castable to a std::string because it seems that typeid(std::string) != boost::any.type(). Only thing which is the same is the string represantation of type().name(). I came around this with my own any_cast implementation: template<typename ValueType> ValueType * any_cast(any * operand) { return operand && (operand->type() == typeid(ValueType) || std::string(operand->type().name()).compare(typeid(ValueType).name())==0) ? &static_cast<any::holder<ValueType> *>(operand->content)->held : 0; } Is there a better way to address this issue? Best regards, Gernot Vormayr

2 2

[multi_array] Warnings on upgrade to 1.34.1
by Mark Ruzon 01 Sep '07

01 Sep '07

This reindex function in multi_array/view.hpp is apparently being compiled with BOOST_NO_SFINAE not being defined. template <class BaseList> #ifdef BOOST_NO_SFINAE void #else typename disable_if<typename boost::is_integral<BaseList>::type,void >::type #endif reindex(const BaseList& values) { boost::function_requires< detail::multi_array::CollectionConcept<BaseList> >(); boost::detail::multi_array:: copy_n(values.begin(),num_dimensions(),index_base_list_.begin()); origin_offset_ = this->calculate_indexing_offset(stride_list_,index_base_list_); } I am getting the following error, because naturally there is no return statement. /usr/include/c++/boost_1_34_1/boost/multi_array/view.hpp: In member function `boost::disable_if<boost::is_integral<BaseList>::type, void>::type boost::detail::multi_array::const_multi_array_view<T, NumDims, TPtr>::reindex(const BaseList&)': /usr/include/c++/boost_1_34_1/boost/multi_array/view.hpp:89: warning: no return statement in function returning non-void Is there a fix for this? Shouldn't there be another #ifdef with a return statement? How do I know if I should define BOOST_NO_SFINAE? Sincerely, Mark Ruzon

3 4

subgraph and bundled properties
by Sam Peterson 01 Sep '07

01 Sep '07

According to the release notes of version 1.33, bundled properties are now supposed to work with the subgraph adapter. I am currently using 1.34 However, I'm receiving a compiler error that I never was before I tried to switch to the subgraph adapter: graph.cpp:569: instantiated from here boost_1_34_1/boost/graph/properties.hpp:355: error: no type named 'vertex_bundled' in 'class boost::subgraph<boos\ t::adjacency_list<boost::setS, boost::vecS, boost::bidirectionalS, Paper, boost::property<boost::edge_index_t, lo\ ng unsigned int, boost::no_property>, boost::no_property, boost::listS> >' The line in question looks like this: put(&Paper::authors, *g, index_map.index_map[atoi(current_paper_id->c_str())], name_index); My bundled properties and graph typdefs look like this: struct Paper { unsigned int paper_id; std::string title; std::vector<std::size_t> authors; std::string subject; std::string description; std::string publisher; std::string date_of_paper; std::string format; std::string identifier; std::string source; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & paper_id; ar & title; ar & authors; ar & subject; ar & description; ar & publisher; ar & date_of_paper; ar & format; ar & identifier; ar & source; } }; typedef boost::adjacency_list_traits<boost::setS, boost::vecS, boost::undirectedS> Traits; typedef boost::adjacency_list< boost::setS, // OutEdgeList container boost::vecS, // Vertex container boost::bidirectionalS, // Directed status Paper, // Vertex bundled properties boost::property<boost::edge_index_t, std::size_t> > PaperGraph_t; typedef boost::subgraph < PaperGraph_t > PaperGraph; typedef boost::graph_traits<PaperGraph>::vertex_descriptor PaperVertex; typedef boost::graph_traits<PaperGraph>::edge_descriptor PaperEdge; Is there anything I'm doing wrong or is this a bug? -- Sam Peterson peabody(a)freeshell.org peabodyenator(a)gmail.com

1 0

[Graph] edge() not working
by David A. Greene 31 Aug '07

31 Aug '07

[Apologies if this has been asked before. Gmane is down and Google didn't return anything interesting.] I have a Boost (1.34.1) Graph declared like this: typedef boost::adjacency_list<boost::setS, // Out edge list type boost::listS, // Vertex list type boost::undirectedS, vertex_property_bundle // Vertex properties // Edge properties > my_graph_type; I want to find out if an edge is in the graph: typedef typename boost::graph_traits<my_graph_type>:: edge_descriptor_type edge; edge e; bool present; boost::tie(e, present) = edge(v1, v2, my_graph); Unfortunately, g++ 4.1.2 doesn't like it: error: no matching function for call to boost::detail::edge_desc_impl<boost::undirected_tag, void*>::edge_desc_impl(void* const&, void* const&, boost::adjacency_list<boost::setS, boost::listS, boost::undirectedS, vertex_property_bundle, boost::no_property, boost::no_property, boost::listS>&) boost-1_34_1/boost/graph/detail/edge.hpp:43: note: candidates are: boost::detail::edge_desc_impl<Directed, Vertex>::edge_desc_impl(Vertex, Vertex, const void*) [with Directed = boost::undirected_tag, Vertex = void*] boost-1_34_1/boost/graph/detail/edge.hpp:41: note: boost::detail::edge_desc_impl<Directed, Vertex>::edge_desc_impl() [with Directed = boost::undirected_tag, Vertex = void*] boost/graph/detail/edge.hpp:35: note: boost::detail::edge_desc_impl<boost::undirected_tag, void*>::edge_desc_impl(const boost::detail::edge_desc_impl<boost::undirected_tag, void*>&) Has anyone else run into this problem before? How does a reference to the graph get passed to edge_desc_impl's constructor? Thanks. -Dave

2 2

Re: [Boost-users] [Graph] edge() not working
by Line B. Reinhardt 31 Aug '07

31 Aug '07

Hi I am not sure I understand your program. But I know I do the same thing to check for existence of edges however I use edge_descriptor (and I work on a directed graph) instead edge_descriptor_type: typedef typename boost::graph_traits<my_graph_type>::edge_descriptor_type edge; I did not know that there was anything called an edge_descriptor_type ?? Does this help?? g++ often give strange error messages. Best regards Line R. -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of David A. Greene Sent: 31. august 2007 02:48 To: boost-users(a)lists.boost.org Subject: [Boost-users] [Graph] edge() not working [Apologies if this has been asked before. Gmane is down and Google didn't return anything interesting.] I have a Boost (1.34.1) Graph declared like this: typedef boost::adjacency_list<boost::setS, // Out edge list type boost::listS, // Vertex list type boost::undirectedS, vertex_property_bundle // Vertex properties // Edge properties > my_graph_type; I want to find out if an edge is in the graph: typedef typename boost::graph_traits<my_graph_type>:: edge_descriptor_type edge; edge e; bool present; boost::tie(e, present) = edge(v1, v2, my_graph); Unfortunately, g++ 4.1.2 doesn't like it: error: no matching function for call to boost::detail::edge_desc_impl<boost::undirected_tag, void*>::edge_desc_impl(void* const&, void* const&, boost::adjacency_list<boost::setS, boost::listS, boost::undirectedS, vertex_property_bundle, boost::no_property, boost::no_property, boost::listS>&) boost-1_34_1/boost/graph/detail/edge.hpp:43: note: candidates are: boost::detail::edge_desc_impl<Directed, Vertex>::edge_desc_impl(Vertex, Vertex, const void*) [with Directed = boost::undirected_tag, Vertex = void*] boost-1_34_1/boost/graph/detail/edge.hpp:41: note: boost::detail::edge_desc_impl<Directed, Vertex>::edge_desc_impl() [with Directed = boost::undirected_tag, Vertex = void*] boost/graph/detail/edge.hpp:35: note: boost::detail::edge_desc_impl<boost::undirected_tag, void*>::edge_desc_impl(const boost::detail::edge_desc_impl<boost::undirected_tag, void*>&) Has anyone else run into this problem before? How does a reference to the graph get passed to edge_desc_impl's constructor? Thanks. -Dave _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

2 1

Locating source file for boost function
by Jaime Rios 31 Aug '07

31 Aug '07

Hello, I'm debugging a dylib built with XCode on a PowerPC G5. As I am stepping through the code, I find that I cannot view the source for the following call: boost::function0<void, std::allocator<boost::function_base> >::operator() The assembly code doesn't tell me much and I am having a hard time locating the source code for this. I thought the code was in the function_template.hpp file, but that is not working either. Thanks in advance! -Jaime

1 0

Boost-users][regex] Can I use NULL char (ascii \x00) as a part of boost_regex regular expression
by Chandan Nilange 31 Aug '07

31 Aug '07

I want to use NULL char i.e ascii \x00 as a part of my regular expression. Does boost_regex support this? For examples: regular expression: ab\0cd matching char sequence: ab\0cd I expect ot get match a match for full expression ab\0cd How can I achieve this using boost_regex. Regards, Chandan. ____________________________________________________________________________________ Luggage? GPS? Comic books? Check out fitting gifts for grads at Yahoo! Search http://search.yahoo.com/search?fr=oni_on_mail&p=graduation+gifts&cs=bz

5 4

Building boost 1.34.1
by James Emerton 31 Aug '07

31 Aug '07

I'm having difficulties building boost 1.34.1 using the intel toolchain. Once bjam tries to invoke the compiler, I get the "Windows cannot open this file" dialog, where the file is an .obj.rsp file. It would appear that perhaps the compiler itself is not making it into the command line, thus causing the system to try executing the .rsp file directly. I am not having this problem if I use the msvc toolchain. Command to invoke the build: bjam --toolset=intel-9.1 Compiler: Intel(R) C++ Compiler for 32-bit applications, Version 9.1 Build 20060519Z bjam: Boost.Jam Version 3.1.14. OS=NT. Some environment variables: ICPP_COMPILER91=C:\Program Files\Intel\Compiler\C++\9.1 INTEL_BASE_MSVC_TOOLSET=vc-7_1 INTEL_LICENSE_FILE=C:\Program Files\Common Files\Intel\Licenses INTEL_PATH=C:\Program Files\Intel\Compiler\C++\9.1\Ia32 INTEL_SHARED=C:\Program Files\Common Files\Intel\Shared Files I've run the iclvars batch script, icl.exe is on the path, and I've used this environment to build boost 1.33 successfully. I've tried various debug levels of bjam, and I haven't seen anything that makes a problem obvious to me. Thanks James

2 1

trouble with enable_if
by Neal Becker 31 Aug '07

31 Aug '07

The following code: template<typename int_t> inline typename boost::enable_if_c<boost::is_integral<int_t>::value, std::complex<int_t> >::value operator >> (std::complex<int_t> const&x, int bits) { return std::complex<int_t> (real (x) >> bits, imag (x) >> bits); } // template<typename int_t> // inline std::complex<int_t> // operator >> (std::complex<int_t> const&x, int bits) { // return std::complex<int_t> (real (x) >> bits, imag (x) >> bits); // } int main() { std::cout << (x >> 1) << '\n'; } gives: error: no match for 'operator>>' in 'x >> 1' (gcc-4.1.2) Uncomment the commented out version (without enable_if) and it compiles. What's wrong here?

2 2

bug in boost::serialization XML
by Robert Bielik 31 Aug '07

31 Aug '07

boost::serialization needs empty XML elements on the form: <ElementName></ElementName> whereas the preferred (and legal) XML empty element syntax is: <ElementName/> boost::serialization chokes on this with a 'stream error' exception. I've found this because I needed to preprocess the XML before serializing into objects and the third party XML lib generates empty elements of the latter form. Thanks /Rob

1 0

caller.hpp(199) : error C2027: use of undefined type
by desai3＠cooper.edu 30 Aug '07

30 Aug '07

I am trying to expose a C++ function in Python. This function does not take any inputs, and it returns a structure which consists of a string array and a multidimentional integer array. When I try to compile it, it gives me following error: c:\boost\boost/python/detail/caller.hpp(199) : error C2027: use of undefined type 'boost::python::detail::specify_a_return_value_policy_to_wrap_functions_returning<T>' with [ T=result_t ] c:\boost\boost/python/detail/caller.hpp(176) : while compiling class template member function 'PyObject *boost::python::detail::caller_arity<1>::impl<F,Policies,Sig>::operator ()(PyObject *,PyObject *)' with [ F=DQEasy *(__thiscall DQEasy::* )(void), Policies=boost::python::default_call_policies, Sig=boost::mpl::vector2<DQEasy *,DQEasy &> ] ///////////// My function looks like this: DQEasy* DQEasy::RequestToResponse() { int size(0); std::string user = "O066144"; std::string url = "dataquery-dev.ny.jpmorgan.com:6555"; DQP* request = getBaseRequest(); addValidContext(request, user); std::string expressionList[] = {"DB(FHR,TB3,MIDYLD)","DB(FHR,TB6,MIDYLD)"}; size = sizeof(expressionList)/sizeof(std::string); DQEasy::addExressions(request, expressionList, size); std::string outputTypeArray[] = {"data","stats"}; size = sizeof(outputTypeArray)/sizeof(std::string); DQEasy::addOutputTypes(request, outputTypeArray, size); DQP *response = DQEasy::getResponse(request, url); DQEasy *output = DQEasy::parseDQP(response); return output; } #include <C:/boost/boost/python.hpp> #include <C:/boost/boost/python/module.hpp> #include <C:/boost/boost/python/def.hpp> using namespace boost::python; BOOST_PYTHON_MODULE(DQEasy) { //Export the class to Python class_<DQEasy>("DQEasy") .def("RequestToResponse", &DQEasy::RequestToResponse) ; } Any clue will be quite helpful. I apologize if the message is too long. Thank you

1 0

[thread] Never enter critical section [NC]
by frederic.mayot＠sgcib.com 30 Aug '07

30 Aug '07

Hi, I'm having a problem with mutexes. In one thread T1 I have: while(!end) { /* TTT */ lock lk(mutex); dosomethingquick(); } In another thread T2 I have: void f() { lock lk(mutex); doanotherthingquick(); } I'm sure dosomethingquick returns but T2 can never acquires the mutex. If I had a timer on line /* TTT */ in T1 (sleeps for a millisecond), everything works fine. Can anyone understand such a behavior? Am I doing something wrong here? Thanks, ____________________________ Frederic MAYOT Société Générale - Equity IT 1221 Avenue of the Americas New York, NY 10020 +1 (212) 278-5558 +1 (917) 673-1339 ************************************************************************* This message and any attachments (the "message") are confidential and intended solely for the addressees. Any unauthorised use or dissemination is prohibited. E-mails are susceptible to alteration. Neither SOCIETE GENERALE nor any of its subsidiaries or affiliates shall be liable for the message if altered, changed or falsified. *************************************************************************

5 8

Boost.CMake's boost_add_executable
by ope 30 Aug '07

30 Aug '07

Hi, I've read http://svn.boost.org/trac/boost/wiki/CMakeAddExecutable and try to use it - and it doesn't work correct. This macros isn't used in the boost cmake build (in real there isn't a wave example as the web page promised)! Anyway, I've got the linker error: /usr/bin/ld: cannot find -lboost_program_options-static It should look for libboost_program_options-gcc41-mt-1_34! The part responsible is at tools/build/CMake/BoostCore.cmake: else (LIB MATCHES ".*-.*") # The user has given the name of just the library target, # e.g., "boost_filesystem". We add on the appropriate variant # name(s). list(APPEND THIS_EXE_ACTUAL_DEPENDS "${LIB}${VARIANT_TARGET_NAME}") list(APPEND THIS_EXE_RELEASE_ACTUAL_DEPENDS "${LIB}${RELEASE_VARIANT_TARGET_NAME}") list(APPEND THIS_EXE_DEBUG_ACTUAL_DEPENDS "${LIB}${DEBUG_VARIANT_TARGET_NAME}") endif (LIB MATCHES ".*-.*") using: boost_add_executable(... DEPENDS boost_program_options-gcc41-mt-1_34 ... ) works! Did I something wrong or is there an error inside boost's BoostConfig.cmake? Thanks, Olaf

3 5

boost::multi_index iterators and std::distance
by Jeffrey Holle 30 Aug '07

30 Aug '07

In experimenting with boost::multi_index, I find that std::distance does not work properly multi_index iterators. My multi_index as a single ordered index for now, and I've tried: C cs; Index& index = cs.get<0>(); ... populate cs Index::iterator iter=index.find(7); cout << "distance is \"" << distance(cs.begin(),iter) << "\"" << endl; cout << "distance is \"" << distance(index.begin(),iter) << "\"" endl; Both outputs print that the distance is 0, and should be 7. Note both output lines compile and I've also tried using operator- and operator+ with the iterators and found that they don't exist (as expected). Is there a work around for this?

2 2

[BGL] add_vertex(vp, graph) with mix of internal & bundled properties
by Sara Ting 30 Aug '07

30 Aug '07

Hello, I need to use the overload of add_vertex that takes the vertex property object as a parameter. I am using a mix of internal and bundled properties because I had to add the vertex_index property but did not want to clutter my bundled property with an index field. How do I instantiate this mixed property object to call add_vertex(vp, graph)? For reference, my graph is defined like this: adjacency_list<vecS, listS, indirectedS, boost::property<boost::vertex_index_t, int, MyNodeProperties>, MyEdgeProperties> I basically want to do this call: add_vertex(myNodeProp, graph) but I am getting a compilation error that it is not a boost::property<....> type. How do I wrap my bundled property in an object that I can pass to this function? Thanks, Sara

2 1

error LNK2019: unresolved external symbol
by desai3＠cooper.edu 30 Aug '07

30 Aug '07

I am using boost build v1, VC 8. While building my project I get following errors, ***************************************************************** DQEasy.obj : error LNK2019: unresolved external symbol "public: bool __thiscall DQP::putString(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,char const *)" (?putString@DQP@@QAE_NABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@PBD@Z) referenced in function "public: class DQP * __thiscall DQEasy::getBaseRequest(void)" (?getBaseRequest@DQEasy@@QAEPAVDQP@@XZ) DQEasy.obj : error LNK2019: unresolved external symbol "public: __thiscall DQP::DQP(void)" (??0DQP@@QAE@XZ) referenced in function "public: class DQP * __thiscall DQEasy::getBaseRequest(void)" (?getBaseRequest@DQEasy@@QAEPAVDQP@@XZ) ******************************************************************** There are 63 unresolved symbols altogether. Any Ideas on how can I fix it? I have tried entering bjam "-sBUILD=<runtime-link>static" instead of bjam, still no help. I am copying my jamfile for reference. Thank you. ********************************************************************* # This is the top of our own project tree project-root ; # Include definitions needed for Python modules import python ; extension DQEasy # Declare a Python extension called DQEasy : DQEasy.cpp # source # requirements and dependencies for Boost.Python extensions <template>@boost/libs/python/build/extension : <include>. ; ***********************************************************************

1 0

Program_options : option couples and order
by Patrick Sizun 30 Aug '07

30 Aug '07

Hi, I would like to know if it's possible, with program_options, to handle the order in which several values of the same options are entered. E.g. : when entering prog -f file1.txt -n 2 -f file2.txt -n 3 I need to get the (f,n) couples right, and the use of the -n option should be mandatory for each file. How is it possible to enforce that? or does it all belong to the post-processing of the options ? Regards, Patrick

1 0

Re: [Boost-users] Program_options assertion failure
by Fletcher, Matthew (Information Technology) 29 Aug '07

29 Aug '07

Well I presume you've already tried turning off the unicode option but I would try recompiling with the setting 'Use Multi-Byte Character Set' and also have 'Treat wchar_t as Built-in Type' set to No. The unicode setting doesn't affect the char *'s, but could certainly affect what happens when you create a std::string from one without explicitly setting a size/allocator. I agree with James that a mismatch between these settings is a very likely cause. Matt -- This e-mail is confidential and the information contained in it may be privileged. It should not be read, copied or used by anyone other than the intended recipient. If you have received it in error, please contact the sender immediately by telephoning +44 (0)20 7623 8000 or by return email, and delete the e-mail and do not disclose its contents to any person. We believe, but do not warrant, that this e-mail and any attachments are virus free, but you must take full responsibility for virus checking. Please refer to http://www.dresdnerkleinwort.com/disc/email/ and read our e-mail disclaimer statement and monitoring policy. Dresdner Kleinwort is the trading name of the investment banking division of Dresdner Bank AG, and operates through Dresdner Bank AG, Dresdner Kleinwort Limited, Dresdner Kleinwort Securities Limited and their affiliated or associated companies. Dresdner Bank AG is a company incorporated in Germany with limited liability and registered in England (registered no. FC007638, place of business 30 Gresham Street, London EC2V 7PG), and is authorised by the German Federal Financial Supervisory Authority and by the Financial Services Authority ('FSA') and regulated by the FSA for the conduct of designated business in the UK. Dresdner Kleinwort Limited is a company incorporated in England (registered no. 551334, registered office 30 Gresham Street, London EC2V 7PG), and is authorised and regulated by the FSA. Dresdner Kleinwort Securities Limited is a company incorporated in England (registered no. 1767419, registered office 30 Gresham Street, London EC2V 7PG), and is authorised and regulated by the FSA.

2 4

metaclass must be exactly Boost.Python.class, not a subclass?
by william.r.chesters＠jpmorgan.com 29 Aug '07

29 Aug '07

Hi, I'd like to create a metaclass M which I can use to construct new Python classes C inheriting from a C++ base class B. B's metaclass is of course "Boost.Python.class", so I inherit M from that. It's not quite working for me though, because when I try to pass an instance of one of the C's back to C++, I get a "TypeError: No registered converter was able to extract a C++ pointer to type B from this Python object of type C". It seems that BP is testing for "type(type(obj)) is Boost.Python.class" rather than "isinstance(Boost.Python.class, type(type(obj))". Is this an easy issue to fix or work around? Many thanks, William This communication is for informational purposes only. It is not intended as an offer or solicitation for the purchase or sale of any financial instrument or as an official confirmation of any transaction. All market prices, data and other information are not warranted as to completeness or accuracy and are subject to change without notice. Any comments or statements made herein do not necessarily reflect those of JPMorgan Chase & Co., its subsidiaries and affiliates. This transmission may contain information that is privileged, confidential, legally privileged, and/or exempt from disclosure under applicable law. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution, or use of the information contained herein (including any reliance thereon) is STRICTLY PROHIBITED. Although this transmission and any attachments are believed to be free of any virus or other defect that might affect any computer system into which it is received and opened, it is the responsibility of the recipient to ensure that it is virus free and no responsibility is accepted by JPMorgan Chase & Co., its subsidiaries and affiliates, as applicable, for any loss or damage arising in any way from its use. If you received this transmission in error, please immediately contact the sender and destroy the material in its entirety, whether in electronic or hard copy format. Thank you. Please refer to http://www.jpmorgan.com/pages/disclosures for disclosures relating to UK legal entities.

1 0

serialization lib, const data, documentation
by Robbie Morrison 29 Aug '07

29 Aug '07

Hello all Regarding the Boost.Serialization library. Archiving to XML requires the use of name-value-pairs for all serialized objects, be they stand-alone or encapsulated. I wanted to confirm the following is correct. In reference to the online and bundled HTML documentation: http://www.boost.org/libs/serialization/doc/serialization.html#const file:///.../boost_1_34_1/libs/serialization/doc/serialization.html#const It would appear that the code block which reads: ar & const_cast<T &>(t); should also mention that, in the case of XML serialization: using boost::serialization::make_nvp; // for convenience ar & make_nvp("t", const_cast<T &>(t)); // cast used on load Moreover, this code could be a candidate for a macro, something like (or would this create its own can of worms?): ar & BOOST_SERIALIZATION_NVP_CONSTDATA(T, t); ar & BOOST_SERIALIZATION_CONSTDATA_NVP(T, t); --- On that note, a new page describing user Boost.Serialization macros and their usage might be helpful. For instance I have created the following list (readers should note that my comments may well be incorrect): BOOST_CLASS_EXPORT_GUID(SubClass, "MySC") // GUID is "globally unique id" BOOST_CLASS_EXPORT(SubClass) // shortcut if class name is acceptable BOOST_CLASS_VERSION(Class, 2) // reset class version, the default is zero BOOST_IS_ABSTRACT(AbstractClass) // only some compilers [which ones ?] BOOST_SERIALIZATION_NVP(data) // shortcut if object name acceptable [1] BOOST_SERIALIZATION_BASE_OBJECT_NVP(Base) // shortcut if object name acceptable [2] BOOST_SERIALIZATION_SPLIT_MEMBER() // 'serialize' to 'save'/'load' BOOST_SERIALIZATION_SHARED_PTR(Class) // depreciated [3] BOOST_CLASS_TRACKING(MyVirtualBaseClass, boost::serialization::track_always) BOOST_SHARED_POINTER_EXPORT(T) // depreciated from Boost version 1.32 BOOST_SHARED_POINTER_EXPORT_GUID(T, K) // depreciated from Boost version 1.32 BOOST_SERIALIZATION_LIBRARY_VERSION // yields a "release" number [4] [1] boost::serialization::make_nvp("data", data); [2] requires #include <boost/serialization/base_object.hpp> [3] more specifically, for types without tracking set, that is using boost::serialization::track_never also under 1.34.1 this generates code only for particular Metrowerks and Borland compilers [4] requires #include <boost/serialization/serialization.hpp> (but doesn't appear to be maintained) I don't mind drafting out such a page. Could it be part of the official web documentation or would I be better to add it to the boost wiki as an informal contribution. many thanks in advance Robbie --- Robbie Morrison PhD student -- policy-oriented energy system simulation Institute for Energy Engineering (IET) Technical University of Berlin (TU-Berlin), Germany [from IMAP client]

1 0

Program_options assertion failure
by Johnathan Bunn 29 Aug '07

29 Aug '07

im having an issue with a project using visual studio pro 2005 if it makes a difference the librarys im using are Qt, pdflib, boost, and some crystal com stuff thorugh activex my problem is that when I build in release my command line args are parsed fine and my application behaves as expected. when I build in debug mode, I get an asertion failure as follows Assertion failed: n == name.size()-2, file libs\program_options\src\options_description.cpp, line 122 the relevent code is as follows // process command line args.. po::options_description desc( "TEST" ); desc.add_options( ) ("help", "produce help message" ); ("hideSplash", "hide splash message" ) ("report", po::value<int>( ), "show requested report and quit" ) ; po::variables_map vm; po::store( po::parse_command_line( argc, argv, desc ), vm ); po::notify( vm ); if( vm.count( "help" ) ){ Log::Info::out( ) << "Help Message requested"; // show help window return true; } there is more blocks the same as the last if block that look for my other messages they are commented out now for testing though I am completely stumped and sought help on the #boost irc channel volodya and others on that channel were stumped as well if anyone has any insight into this issue I thank you in advance for your help :-D -- To follow the Path, Look to the master, Walk with the master, See through the master, Become the master

3 3

Boost Parameter Question.
by Surya Kiran Gullapalli 29 Aug '07

29 Aug '07

Hello all, I'm a newbie to boost parameter library. I had no problem in using BOOST_PARAMETER_MEMBER_FUNCTION as long as the function is non static. what is the macro to use for static member function. I gave BOOST_PARAMTER_MEMBER_FUNCTION ( (static void), ... ) But i was getting warning messages with MSVC 8.0 compiler, with boost-1.34.1 warning C4042: 'unnamed-parameter': has bad storage class. I do not know whether these are harmless or not. Please help. Thanks, Surya

2 1

[boost::format] How to not display 0 integer?
by tomasz2k＠poczta.onet.pl 29 Aug '07

29 Aug '07

Hello group I'm using boost::format heavily to format my output for user. I've run into a problem that I cannot resolve for now. I use this format: int i = 4; cout << format ("(%|1$+2|)") % i; // -> (+4) i = -4; cout << format ("(%|1$+2|)") % i; // -> (-4) That's fine and expected. But my question for the one below: int i = 0; cout << format ("(%|1$+2|)") % i; // -> ( 0) // -> ( ) how? How to avoid printing 0? I want formatter to print values in plus or in minus only. When there's value 0 - display only spaces to width. My problem is that I cannot create wrapper over that integer, I must feed formatter with int for various reasons. Does anyone know how to achive this? Maybe I override some parts of library or parsing method? Maybe some of you added your own formatts to formatter and want to share? Any hint or example would be valuable. Thanks in advance, Tomasz Kalkosiñski

1 0

warning C4180 in VS 2005 for bind.hpp
by Adam Badura 29 Aug '07

29 Aug '07

I have a large project at work. We use Visual Studio 2005 with SP 1 and Boost 1.34.0. When we use boost::bind in algorithms on collections we very often get following warning (at level 3): J:\ThirdParty\boost_1_34_0\boost/bind.hpp(1575) : warning C4180: qualifier applied to function type has no meaning; ignored the detailed message is following (just an example extract from compilation log, sadly I was unable to produce a simple stand-alone example - but if it is required then I will give some more work into finding one): J:\ThirdParty\boost_1_34_0\boost/bind.hpp(1575) : warning C4180: qualifier applied to function type has no meaning; ignored J:\ThirdParty\boost_1_34_0\boost/bind.hpp(1609) : see reference to class template instantiation 'boost::_bi::add_cref<Pm,I>' being compiled with [ Pm=boost::shared_ptr<nle::views::ScrollEventListener> , I=1 ] j:\sources\Common/Helpers/Observable.h(128) : see reference to class template instantiation 'boost::_bi::dm_result<Pm,A1>' being compiled with [ Pm=boost::shared_ptr<nle::views::ScrollEventListener> (__thiscall boost::weak_ptr<nle::views::ScrollEventListener>::* )(void), A1=boost::arg<1> ] j:\sources\Common/Helpers/Observable.h(120) : while compiling class template member function 'void common::helpers::Observable<T>::registerListener(const boost::weak_ptr<T> &) const' with [ T=nle::views::ScrollEventListener ] j:\sources\NLE/Views/ScrollInfo.h(65) : see reference to class template instantiation 'common::helpers::Observable<T>' being compiled with [ T=nle::views::ScrollEventListener ] One of my colleagues found a "solution" to this problem. If the modifier "const" is removed in one of typedef's the no warning are generated. However we would like a better solution since modifying the library doesn't seem a good one. What to do? Adam Badura

3 2

Graph: "extra" edge processing during BFS
by Eric Fowler 29 Aug '07

29 Aug '07

I have an algorithm that just screams breadth first search. After some thrashing around in the graph library I am confident in about 90% of the implementation. However there is one little snag: When I examine a grey vertex, I want to do some basic logic on the vertex and the "candidate" next edge to see if what I want to do with this edge and this vertex is "legitimate", according to my own definition of legitimacy(*). If the edge is good, I use it, perhaps relaxing it, if not, I just pass on it and go on to the next one. I would like to do this without tweaking or rewriting the BFS algo. Can this be done with just visitors and the various template parameters or must I write my own BFS variant (not that hard to do of course)? Eric * My idea of "legitimate" is to check to see if a path to a given vertex already contains a certain vertex. The path is built as I run the algorithm. "Parent" vertices are stored as the algorithm runs so I can follow a chain up from the examined vertex back to the root. So the basic logic is: Vertex u = Q.top(); Q.pop(); vis.examine_vertex(u, g); //this is already in BFS if(has_certain_property(u, g)) add_to_tree(u, g); else do_not_add(u, g); .... etc.

1 0

Different functions based on type of iterator?
by HighCommander4 29 Aug '07

29 Aug '07

Let's say I had a function template <typename Iterator> void function(Iterator first, Iterator last); and I want it to call two different functions based on if Iterator is a random access iterator or just a forward iterator. Essentially, I want two versions of this function: template <typename RandomAccessIterator> void function(RandomAccessIterator first, RandomAccessIterator last); template <typename ForwardIterator> void function(ForwardIterator first, ForwardIterator last); I want a function call to function(a, b) to translate to the first one if a and b are random access iterators, and the second one if they are not. I'm thinking of somehow combining enable_if and concept checking, I'm just not sure how... -- View this message in context: http://www.nabble.com/Different-functions-based-on-type-of-iterator--tf4345… Sent from the Boost - Users mailing list archive at Nabble.com.

1 0

Linking to DLLs on Windows with GCC
by John Pye 29 Aug '07

29 Aug '07

Hi all, I am having trouble linking against Boost DLLs. Even though I think I am using the correct compiler commands, I seem to end up with statically linked binaries (everything works fine, but Dependency Walker shows that I have no DLL dependency on Boost). Specifically, I am trying to link against Boost:Serialization. Because I'm using MinGW, my Boost libraries had to be compiled by me, so I used "bjam --toolset=gcc --layout=system". I then ran "bjam install" with the same options, which resulted in (over 1GB of) files in c:\Boost. Next I build my own program. It compiles against the Boost files using GCC parameters "-IC:\Boost\include" and then links against Boost::Serialisation using "-LC:\Boost\lib" -lboost_serialization-mt So, what can I do to set GCC to use dynamic linking to the DLL in this case, instead of the static linking that it appears to be using at the moment? (I am a little unclear about the purpose of the .a files currently present in the c:\Boost\lib directory. Do they refer in some way to the DLLs or are they self-contained static libraries?) Cheers JP

1 0

[ptr_container]Swap/reorder elements in ptr_vector
by Bill Buklis 28 Aug '07

28 Aug '07

What is the best or recommended way to swap or reorder elements in a ptr_vector? Naturally, I simply want to swap pointers and not copy any elements. Using swap with the "base" iterator works (see below), but it feels like I'm using an undocumented feature or something. Is there a preferred method? Or is this the best approach? typedef boost::ptr_vector<int> VEC; VEC v; v.push_back( new int(1) ); v.push_back( new int(2) ); VEC::iterator a = v.begin(); VEC::iterator b = v.begin() + 1; // Swap the two underlying pointers using the base iterator std::swap( *a.base(), *b.base() ); -- Bill --

1 0

Adding content to a vertex in a graph
by Stephen Torri 28 Aug '07

28 Aug '07

I made this property graph according to the documentation: class Component { public: typedef boost::shared_ptr<Component> ptr_t; }; class My_Graph { typedef boost::property< boost::vertex_name_t, Component::ptr_t > VertexProperty_t; typedef boost::adjacency_list<boost::vecS, // OutEdgeList boost::vecS, // VertexList boost::directedS, // Directed VertexProperty_t> // VertexProperties Graph_t; Graph_t m_graph; }; I cannot see from the MutablePropertyGraph page how I am suppose to add the VertexProperty_t to the vertex when its created. The documentation for the MutablePropertyGraph shows a use of "add_vertex" giving a vertex_propety_type with the graph. template <class G> struct MutablePropertyGraphConcept { typedef typename boost::graph_traits<G>::edge_descriptor edge_descriptor; void constraints() { function_requires< MutableGraphConcept<G> >(); v = add_vertex(vp, g); p = add_edge(u, v, ep, g); } G g; std::pair<edge_descriptor, bool> p; typename boost::graph_traits<G>::vertex_descriptor u, v; typename boost::graph_traits<G>::vertex_property_type vp; typename boost::graph_traits<G>::edge_property_type ep; }; My confusion lies in the fact that the add_vertex function requires a vertex_property_type the first parameter. So I am unsure how to create a vertex_property_type from a Component::ptr. Is a vertex_property_type equivalent to a Component::ptr? boost::graph_traits<Graph_t>::vertex_property_type vertex_propert_obj = Component::ptr ( new Component() ); boost::graph_traits<Graph_t>::vertex_descriptor new_vertex = add_vertex ( vertex_property_obj, m_graph ); Stephen

1 0

[BGL] Bundled Properties and setS Edgelist container
by Sam Peterson 28 Aug '07

28 Aug '07

I know that if I use a setS for the edgelist container for an adjacency_list class, each edge of my graph will only be added once as I build it. This functionality is very desirable for me, but I've found I can't seem to use it with the equally desirable Bundled Property Maps. Specifically, this line of code doesn't seem to work: (*g)[i].paper_id = atoi(row[0]); g is a pointer to my graph. The exact compiler error with g++ 4.1.1 is: error: invalid conversion from 'size_t' to 'void*' Is there anyway I can use these two features together? If not, I'm going to be very disappointed. If that's the case I'd advise making a large note of it in the bundled properties documentation as I wouldn't have bothered with bundled properties if I knew they carried this limitation. -- Sam Peterson peabody(a)freeshell.org peabodyenator(a)gmail.com

3 7

Short mailing list outage at 9:00PM EDT
by Doug Gregor 28 Aug '07

28 Aug '07

There will be a brief outage of the Boost mailing lists from 9:00PM-9:30PM EDT today. No mail will be lost. Subversion and the Trac will still be available during this time. - Doug

1 0

[BGL] read_graphviz and dynamic properties
by Sam Peterson 28 Aug '07

28 Aug '07

I have been trying (unsuccessfully for the past hour), to read a graphviz file into an adjacency_list type. The program stops with a SIGABRT because I haven't mapped "node_id" to anything within the dynamic properties argument. However, I really have no desire to map node_id to anything; this is a very large graph and I'd like to avoid the memory consumption. If I try to map node id to the vertex_index_t map I receive a compiler error stating that's a const property map. If I want to map node_id to vertex_name_t map, I have to add that property to my adjacency_list type which will bloat the memory consumption. I just want to build the graph without worry about the properties. Is there anyway this can be done easily? The documentation on read_graphviz and write_graphviz are sorely lacking on this subject in my opinion. -- Sam Peterson peabody(a)freeshell.org peabodyenator(a)gmail.com

2 3

boost undefined reference md5.
by chun ping wang 28 Aug '07

28 Aug '07

while trying to link to lib boost md5 i get these errors I build using make with -l"boost_md5-mgw41-1_34_1. booost md5 was build using gcc 4.1.2 mingw. C:/Boost/include/boost-1_34_1/boost/md5.hpp:33: undefined reference to `boost::md5::context::context()' C:/Boost/include/boost-1_34_1/boost/md5.hpp:33: undefined reference to `boost::md5::context::context()' C:/Boost/include/boost-1_34_1/boost/md5.hpp:57: undefined reference to `boost::md5::process(void const*, unsigned int, bool)' C:/Boost/include/boost-1_34_1/boost/md5.hpp:46: undefined reference to `boost::md5::clear()' C:/Boost/include/boost-1_34_1/boost/md5.hpp:46: undefined reference to `boost::md5::clear()'

1 0

[Boost.Test] User Exception handling
by Ewgenij Sokolovski 28 Aug '07

28 Aug '07

Hello. On the webpage I read: In case if your test cases may throw custom exceptions (see here for list of exceptions translated by default), you could register translator specific for that exception. http://www.boost.org/libs/test/doc/components/utf/index.html So, if I understand it right, if I throw some custom exception in my test program and do not catch it, then it is catched by the boost test framework and reported in the proper way - if the exception can be translated by default. Now I look at the exceptions, which can be translated by default and see: In majority of the cases the monitored function doesn't need to throw the boost::execution_exception to report an error in the Execution Monitor. If you want a custom error message to be included into the execution_exception's error message, use one of the following C++ types as an exception: * C string. * std:string. * any exception class in std::exception hierarchy. http://www.boost.org/libs/test/doc/components/execution_monitor/index.html#… So, I can use a C string for my exception. I have written a small example test case and included throwing of an uncaught exception in it: try{ throw "blub"; } catch(char* ex){ throw; } As I started the testing process I didn't get a "blub"-Exception message, but Boost.Test internal framework error: unknown reason So, what's wrong? Why is "blub" not reported as "blub"? Can anybody explain that? Regards Ewgenij

6 8

Serialization in an array
by Hansi Hansi 27 Aug '07

27 Aug '07

Hello, is it possible to serialize a class in a byte-array(e.g. array stream)? best regards Hansjörg _______________________________________________________________________ Jetzt neu! Schützen Sie Ihren PC mit McAfee und WEB.DE. 3 Monate kostenlos testen. http://www.pc-sicherheit.web.de/startseite/?mc=022220

3 2

boost::thread Destructor being called multiple times
by kaliwanagan 27 Aug '07

27 Aug '07

I was just curious as to why the class destructor are (apparently) being called multiple times. I have tried searching the archives to no avail (which prompted me to register and post to the mailinglist). #include <boost/thread/thread.hpp> struct TestingClass { TestingClass() { std::cout << "constructor called" << std::endl; } ~TestingClass() { std::cout << "destructor called" << std::endl; } void operator()() { std::cout << "operator() called" << std::endl; } } testclass; void testBoostThread() { boost::thread thrd (testclass); thrd.join(); } int main () { testBoostThread(); return 0; } The output: constructor called destructor called destructor called destructor called destructor called operator() called destructor called I would appreciate if someone can enlighten me on this. Will having the destructor called multiple times be a cause of concern? Will it cause some undefined symptoms? Is there a way to completely avoid this situation?

4 3

[boost-users][serialization]How to build the whole serialization regression test suite?
by wei niu 27 Aug '07

27 Aug '07

I find run_archive_test.bat, runtest.bat and Jamfile in boost_1_33_1\libs\serialization\test folder. Then I executed run_archive_test.bat,it output: run_archive_test "<test header file>" "<toolset>" "[<boost root directory>]" "[<target directory>]" I didn't know how to give a proper parameter of "test header file".So after reading runtest.bat file I entered command "bjam --dump-test -sTOOLS=vc-7_1 test". It really worked and generated a lot of folders in boost_1_33_1\bin\boost\libs\serialization\test folder and fast consumed all of the free 0.9GB storage space. But I still didn't know how to run so much test files.I executed one of them,it reported sth like "cannot find test_main function".

1 0

[Serialization]Cannot serialize pointer -- newbie needs help
by wei niu 27 Aug '07

27 Aug '07

I cannot serialize an object through a pointer.When running the program,it reports: This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information. Below is the code : ////////////////////////////////////////////////////////////////////////////////////////////// // // static link library: libboost_serialization-vc71-s-1_33_1.lib // ////////////////////////////////////////////////////////////////////////////////////////////// #include <iostream> #include <fstream> #include <list> #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/serialization/base_object.hpp> #include <boost/serialization/utility.hpp> #include <boost/serialization/list.hpp> using std::cout ; using std::endl ; class gps_position { public: int m_degrees ; int m_minu float m_seconds ; gps_position() { m_degrees = m_minutes = m_seconds = 0 ; } gps_position( int degrees, int minutes, float seconds ) { m_degrees = degrees ; m_minutes = minutes ; m_seconds = seconds ; } }; std::ostream& operator << ( std::ostream &out, const gps_position &g ) { return out << g.m_degrees << '\'' << g.m_minutes << '\'' << g.m_seconds; } namespace boost{ namespace serialization{ template <class Archive> void serialize( Archive &ar, gps_position &g, const unsigned int version ) { ar & g.m_degrees ; ar & g.m_minutes ; ar & g.m_seconds ; } } } class bus_stop { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & latitude; ar & longitude; } gps_position latitude; gps_position longitude; protected: bus_stop(const gps_position & lat_, const gps_position & long_) : latitude(lat_), longitude(long_) {} public: bus_stop(){} // See item # 14 in Effective C++ by Scott Meyers. // re non-virtual destructors in base classes. virtual ~bus_stop(){} friend std::ostream& operator << ( std::ostream &out, const bus_stop &bs ) ; }; std::ostream& operator << ( std::ostream &out, const bus_stop &bs ) { return out << bs.latitude << '\t' << bs.longitude ; } class bus_stop_corner : public bus_stop { friend class boost::serialization::access; std::string street1; std::string street2; virtual std::string description() const { return street1 + " and " + street2; } template<class Archive> void serialize(Archive &ar, const unsigned int version) { // save/load base class information ar & boost::serialization::base_object<bus_stop>(*this); ar & street1 & street2; } public: bus_stop_corner(){} bus_stop_corner(const gps_position & _lat, const gps_position & _long, const std::string & _s1, const std::string & _s2 ) : bus_stop(_lat, _long), street1(_s1), street2(_s2) { } friend std::ostream& operator << ( std::ostream &out, const bus_stop_corner &bsc ) ; }; std::ostream& operator << ( std::ostream &out, const bus_stop_corner &bsc ) { return out << dynamic_cast<const bus_stop&>(bsc) << ' ' << bsc.description() ; } class bus_route { friend class boost::serialization::access; bus_stop * stops[2]; template<class Archive> void serialize(Archive & ar, const unsigned int version) { int i; for(i = 0; i < 2; ++i) ar & stops[i]; } public: bus_route() { stops[0] = stops[1] = 0 ; } bus_route( bus_stop *bs1, bus_stop *bs2 ) { stops[0] = bs1, stops[1] = bs2 ; } }; int main() { const char *file_name = "non_intrusive.dat" ; bus_stop *bs0 = new bus_stop_corner( gps_position(34, 135, 52.560f), gps_position(134, 22, 78.30f), "24th Street", "10th Avenue" ); bus_stop *bs1 = new bus_stop_corner( gps_position(35, 137, 23.456f), gps_position(133, 35, 54.12f), "State street", "Cathedral Vista Lane" ); const bus_route br( bs0, bs1 ) ; { std::ofstream ofs( file_name ) ; boost::archive::text_oarchive oa( ofs ) ; oa << (br) ; } bus_route newbr ; { std::ifstream ifs( file_name ) ; boost::archive::text_iarchive ia( ifs ) ; ia >> newbr ; } return 0 ; } I think maybe it's because I didn't build the serialize library correctly.Ibuilded it with bjam.When debuging it with VS2003,an exception was thrown in the _heap_alloc_base (size_t) function at line 211: line 211: return HeapAlloc(_crtheap, 0, size); Function "void * __cdecl _heap_alloc_base (size_t size)" is in malloc.c.

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[1.33] [signals] auto_ptr and boost::signals
by Seweryn Habdank-Wojewódzki 26 Aug '07

26 Aug '07

Dears I have question. Why there are problems to connect function that returns auto_ptr to the signal? Below there is a code which won't compile i line where is comment. Regards. #include <iostream> #include <boost/signals.hpp> #include <boost/shared_ptr.hpp> #include <boost/bind.hpp> #include <memory> #include <vector> #include <iterator> #include <algorithm> class some_class { public: ::std::vector <int> func1() { using ::std::vector; typedef vector <int> Res; Res res (2); res.at(0) = 13; res.at(1) = 14; return res; } ::boost::shared_ptr < ::std::vector <int> > func2() { using ::std::vector; using ::boost::shared_ptr; typedef shared_ptr < vector <int> > Res; Res res (new vector<int> (2)); res->at(0) = 23; res->at(1) = 24; return res; } ::std::auto_ptr < ::std::vector <int> > func3() { using ::std::vector; using ::std::auto_ptr; typedef auto_ptr < vector <int> > Res; Res res (new vector<int> (2)); res->at(0) = 33; res->at(1) = 34; return res; } }; int main() { using ::boost::signal; using ::std::vector; using ::std::auto_ptr; using ::boost::shared_ptr; using ::boost::bind; some_class sc; signal < vector <int> (void) > sig1; signal < shared_ptr < vector <int> > (void) > sig2; signal < auto_ptr < vector <int> > (void) > sig3; sig1.connect (bind (&some_class::func1,&sc)); vector <int> ret1 (sig1()); ::std::copy (ret1.begin(), ret1.end(), ::std::ostream_iterator<int> (::std::cout, "\n")); sig2.connect (bind (&some_class::func2,&sc)); vector <int> ret2 (*sig2()); ::std::copy (ret2.begin(), ret2.end(), ::std::ostream_iterator<int> (::std::cout, "\n")); sig3.connect (bind (&some_class::func3,&sc)); //sig3(); // <- ERROR } -- |\/\/| Seweryn Habdank-Wojewódzki \/\/

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Boost Unit Test Undefined Reference
by cmicel1＠cct.lsu.edu 26 Aug '07

26 Aug '07

Am I missing something when I get undefined references to main using boost 1.34.1. Here is a minimal example #include <iostream> #include <boost/test/unit_test.hpp> void my_test_function() { std::cout << "hi there" << std::endl; } boost::unit_test::test_suite* init_unit_test_suite( int , char*[] ) { boost::unit_test::test_suite* test = BOOST_TEST_SUITE( "Master test suite" ); test->add( BOOST_TEST_CASE( &my_test_function ) ); return test; } This is copied off of the main page. Here is the compilation line g++ test.cpp -o test -lboost_unit_test_framework-gcc41 With gcc version 4.1.2 Here is the error message: /usr/lib/gcc/i486-linux-gnu/4.1.2/../../../../lib/crt1.o: In function `_start': (.text+0x18): undefined reference to `main' collect2: ld returned 1 exit status Any insight? Chris Miceli

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Re: [Boost-users] boost::thread Destructor being called multiple times
by Nat Goodspeed 26 Aug '07

26 Aug '07

At 09:51 AM 8/25/2007, kaliwanagan wrote: >I was just curious as to why the class destructor are (apparently) >being called multiple times. I have tried searching the archives to no >avail (which prompted me to register and post to the mailinglist). Try defining an explicit copy constructor with a message like the others. I believe the issue is that your object is being passed by value, and being copied a few times along the way. You're not seeing your no-args constructor message because the other new instances are invoking the copy constructor.

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Unable to work out a Composite predicate.
by PJ Durai 25 Aug '07

25 Aug '07

Hello everyone, I am not able to figure out the correct syntax for something I am trying to do. The following works as expected. It filters all the 'new' events into a new vector. remove_copy_if ( myEvents.begin(), myEvents.end(), back_inserter(newEvents), !(boost::bind(&Event::GetEventType, _1) == EventType_New)); I cant figure out how to get a complex conditional working as the predicate. e.g. remove_copy_if ( myEvents.begin(), myEvents.end(), back_inserter(newEvents), (boost::bind(&Event::GetEventType, _1) == NotesEventType_New) && (boost::bind(&Event::GetEventID, _1) == 1000 ) ); I have tried various ways of putting parens around this expression. I just couldn't get it to compile. Is that even possible ? Please Advise. I am using Visual C++ 2005 SP1 on Windows XP SP2. Appreciate your time. thanks pj

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Re: [Boost-users] Serialization newbie needs help
by Dominick Layfield 25 Aug '07

25 Aug '07

"Robert Ramey" <ramey(a)rrsd.com> wrote: >> goes away. Any chance this could be added to a boost::serialization >> FAQ? > > you mean change the section named "rationale" to "FAQ"? Ermm... Yes, I suppose so. There ought to be some section that a newbie who is having problems would immediately look to see if this is a common problem. In my browser, the "Rationale" section of the documentation appears unexpanded by default. And even when I expand it, "Compile time trap when saving a non-const value" doesn't seem (when skimming the docs) relevant to the static assertion error. It also didn't appear in my Google search for the cryptic error message that the compiler produced. >> The "Compile time trap" section of the documentation doesn't actually >> explain what "object tracking" is all about. Neither (amusingly) >> does the Boost->Serialization->Reference->Special >> Considerations->Object Tracking section! > > Hmmm - well it's intended to. Maybe I just thought the meaning of the > term "Object Tracking" obvious. As a newbie, I can tell you that it wasn't obvious to me! :-) As I said, I wouldn't have expected the serialization library to do any automagical pointer stuff, so from this perspective, it's very hard to see what object tracking is, and why it would be necessary. >> What on earth does it actually mean to serialize a pointer? > > Exactly what you think it means - see above. Well, once you've got an idea in your head about what should happen when a pointer is serialized (and had that concept for years, and written a whole library to implement it!), it probably seems obvious and "natural" that it should work that way. But to a newbie (to boost::serialization, not to C++), this behavior is rather surprising. For example if I do: my_class mc; my_class* mc_ptr = &mc; cout << mc_ptr; I don't get the my_class object sent to stdout. I get the value of the pointer itself. If I wanted the actual object displayed, I would dereference the pointer. So my intuition would be that boost::serialization would work in a similar way: if I wanted the object itself output/input, I would do it explicitly. I'm not trying to say that your approach is wrong. All I'm attempting to point out is that other people may have very different (and quite reasonable) expectations about what should happen. >> And why would I want to do such a thing, anyway? > > I don't know what your application is. Sorry. What I meant was "Why would someone want this?" or "Why is this a useful feature?" Fundamentally, there are two approaches to dealing with pointer serialization: (1) disallow it altogether; or (2) serialize the pointed-to object, and do all the clever object-tracking stuff. The first approach has the benefit of simplicity . So the only reason to take the second approach would be if automagic pointer serialization is really useful. However, I can't think of an example of when this would be really useful. Hence my question. But if you could provide me an example of when pointer serialization shines, then I would say "Aha! Now I understand why Robert went to so much trouble to make this work.", and I could be at peace with the world again! :-) BTW, I don't want to sound like I'm bashing your library, so let me end with a compliment. I think the symmetric design of serialize(), with the same function used for both input and output, is one of the prettiest idioms I've seen in years. -- Dominick

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[boost::multi-index] improvement suggestion
by Ovanes Markarian 24 Aug '07

24 Aug '07

Hello all, working with boost multi-index container requires sometimes some effort in regards of correct tagging (or at least some typing work ;). I found the following approach to be useful and may be it can be integrated in the multi-index library. First of all the dealing with searchable collections (STL collections are no exception) can be really nasty in regards of finding an iterator and comparing it with the end iterator. The following function can really be of help: /// template function to dermine if the container contains the key specified /// @param T - container type /// @param K - key type /// @param container - container to search for a key /// @param key - key to be found in the container /// \return iterator_range containing the begin and end iterator of the found key. begin iterator equals end iterator the range is empty => nothing found template<class T, class K> inline boost::iterator_range<typename T::const_iterator> find_range(T const& container, K const& key) { return boost::make_iterator_range(container.find(key),container.end ()); } //non-const version follows as well ... Actually iterator_range defines a "bool"- and "!"- (NOT) operators. iterator_range is returned by this function. Therefore constructs like: std::set<std::string> some_set; if(!find_range(some_set, "my_key")) some_set.insert("my_key"); are possible without the need of accesing the underlying iterator types or explicitly comparing the found iterator with the end iterator. The next step dealing with Multi-Index container turned out in multiple typedefs for every tagged type. The main disadvantage in this approach was to constantly retrieve the required container view and related iterator, so I came up the the following class: /// helper class used to retrieve multi-index values dependent on the view tag template<class Tag_, class MultiIndex_> struct value_retrieval { /// type definition used to produce tag dependent view typedef typename MultiIndex_::index<Tag_>::type view_type; /// type definition for the const iterator through the view typedef typename view_type::const_iterator citer_type; /// iterator range used to represent the result typedef boost::iterator_range<citer_type> result_type; /// initializing ctor /// initializes the contained view by using the specified Tag_ type value_retrieval(MultiIndex_ const& mi) : view_(mi.get<Tag_>()) {} /// find a type at the key specified /// @param LookUpType_ - key type /// @param key - key instance to be found template<class LookUpType_> result_type at(LookUpType_ const& key)const { return find_range(view_, key); } private: /// view reference view_type const& view_; }; This class deals with constant views, since I did not require changeable ones, but as one can see the "at"-function can either be used to identify the found iterator range or just to make a check if such a key exists. Dealing with this type is more easier, as to define multi-index accessed view and iterator types. Sample typedef multi_index_container < some_type , indexed_by < .... > > my_container; typedef value_retrieval<my_container, tag_name> by_name; typedef value_retrieval<my_container, tag_value> by_value; //somewhere in code by_name value_by_name(some_container_inst); //if typename is required prefix it... by_name::result_type r = value_by_name.at("some key"); if(r) /// do smth with r Best Regards, Ovanes

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Serializeable Boost hashmap with vector<long> as key
by Oliver Kania 24 Aug '07

24 Aug '07

Hello ! I am looking for a hashmap that is boost::serializeable, has good performance and is implemented by boost-means. Furthermore, it must have vector<long> as key type. I tried multiindex, but it seems one cannot have keys that are not members of the value type. Boost Bimap is not serializeabel and i do not need the bimap functionality. regards, Oliver

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