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[interprocess] set doesn't work when key_type is pointer.
by skywalker 26 Mar '11

26 Mar '11

Hello all, It seems that boost::interprocess::set won't compile if the key_type is pointer. However, bip::vector or std::set works fine. I'm using g++ 4.5.2 and boost 1.46.0 with linux 2.6.37. Here is my code: // compile command: g++ a.cpp -lboost_thread namespace bip = boost::interprocess; struct comp { template<class Pointer> bool operator()(Pointer a, Pointer b) const { return *a < *b; } bool operator()(int a, int b) const { return a < b; } }; typedef bip::managed_mapped_file::segment_manager segment_manager_t; #define fset(value_t) \ bip::set<value_t, comp, bip::allocator<value_t, segment_manager_t> > bip::managed_mapped_file managed_shm(bip::open_or_create, "/tmp/bip_test", 1024); void bip_example() { fset(int*) s(comp(), managed_shm.get_segment_manager()); s.insert(new int (7)); ///< error: key_type can't be pointer in bip. fset(int) s2(comp(), managed_shm.get_segment_manager()); s2.insert(int (7)); ///< ok: non-pointer is accepted. std::set<int*, comp> s3; s3.insert(new int (7)); ///< ok: int* works with STL, as well as shared_ptr, offset_ptr. } void more_example() { typedef bip::offset_ptr<int> optr; fset(optr) s3(comp(), managed_shm.get_segment_manager()); bip::allocator<int, segment_manager_t> alloc_int = managed_shm.get_segment_manager(); optr p = alloc_int.allocate(1); alloc_int.construct(p, 7); s3.insert(p); ///< error: bip doesn't work with offset_ptr too. typedef boost::shared_ptr<int> sptr; fset(sptr) s4(comp(), managed_shm.get_segment_manager()); s4.insert(sptr(new int(7))); ///< ok: shared_ptr works fine. } Won't that fail to compile, or am I missing something? Regards, Tianjiao

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[Graph] Difference between DF search and visit / Graph Printing
by Marcus Riemer 26 Mar '11

26 Mar '11

Hi there! I am struggling a little understanding the difference between the DF search and visit. I thought that the DF visit would revisit "back" nodes while the DF search would not. But as I just found out that does seem to be the difference. What I want: I would like to print all following nodes for every node of a acylic graph. Lets say I have this very simple graph, I hope spaces are preserved: -> Long \ Begin / -> End \ -> -> Short / I would like to print that graph in the following Fashion: Begin .Long ..End .Short ..End I don't mind the exact order of "Long" and "Short", as long as they are both printed. So far I did this by implementing the following dfs_visitor<> [0]. I then apply the visitor with a call to boost::depth_first_visit() and my graph. However, the problem is, that the "End" node is only visited, and therefore printed, once. Of course I could roll out the DF visit myself, but as I will be demonstrating this at my unversity, I would prefer a clean solution. So what am I probably missing to print the graph in the fasion I want it? [0] http://pastebin.com/u43TtU7F

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encryption with boost.iostreams
by Sean Farrow 26 Mar '11

26 Mar '11

Hi: I'm currently writing a serialization routine that needs to encrypt data. Are there any examples of using encryption with boost.iostreams. Also, given an xml file I need to determine that a file is encrypted and then decrypt the file. Anyone got any experience with this? Cheers Sean.

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[units] unit conversion on construction in relation to argument passing
by alfC 25 Mar '11

25 Mar '11

Hi, Boost.Units offers automatic conversion (if conversion factor is defined) on construction of variables: quantity<cgs::lengh> A = 4.*cgs::centimeter; quantity<si::length> a(A); nice! But for some reason I believe this would work for argument functions double f(quantity<si::length> v){ return 1.;} ... quantity<cgs::lengh> A = 4.*cgs::centimeter f(A); // doesn't work! not matching function why is this? isn't the argument of the call a sort of construction argument for the function argument, or is more like a plain assignment. Is there a way to force the automatic conversion of the function call. Or I am forced to use this other long call? f(quantity<si::length>(A)); Thanks Alfredo Full code: #include<boost/units/systems/si.hpp> #include<boost/units/systems/cgs.hpp> double f(quantity<si::length> v){ return 1.; } int main(){ quantity<cgs::length> A(4.*cgs::centimeter); f(A); //not matching function return 0; }

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Assertion `!pthread_mutex_destroy(&m)' failed.
by Panagiotis Foteinos 25 Mar '11

25 Mar '11

Hello users. I am new to boost:threads, so my apologies in advance. I am getting an assertion failure right before main() exits. Specifically, I get the following error: "*/usr/include/boost/thread/pthread/mutex.hpp:45: boost::mutex::~mutex(): Assertion `!pthread_mutex_destroy(&m)' failed.*" Below is the code snippet: *********************************************************************************************************************************** class Test { private: boost::mutex mtx; public: int counter; Test() { counter = 10; } void DoWork() { for(unsigned int i = 0; i < 1000000; i++) { mtx.try_lock(); counter++; mtx.unlock(); } } }; int main() { unsigned int N = 7; boost::thread* test_threads = new thread_type[N]; for(unsigned int i = 0; i < N; i++) { test_threads[i] = thread_type(boost::lambda::bind<void>(&Test::insert, &object)); } for(unsigned int i = 0; i < N; i++) { test_threads[i].join(); } return 1; } *********************************************************************************************************************************** Can somebody shed some light? Main() exits normally, if I replace mtx.try_lock() with mtx.lock(). Why this behavior? Best Regards, Panagiotis Foteinos

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Fw: Boost.thread - infinite thread and expired thread object
by Emil Kaffeshop 25 Mar '11

25 Mar '11

--- On Fri, 3/25/11, Emil Kaffeshop <emildg(a)yahoo.com> wrote: > From: Emil Kaffeshop <emildg(a)yahoo.com> > Subject: Boost.thread - infinite thread and expired thread object > To: boost-users(a)lists.boost.org > Date: Friday, March 25, 2011, 7:16 PM > Hello all, > > I am new to the group and boost. > > I have a question. > > void f (void) > { > while (1) > { > //do thread job > } > } > > void start_thread () > { > boost::thread t(f); > } > > void main (void) > { > start_thread (); > pthread_exit (NULL); > } > > What are consequence for the thread "f" from disappearing > of thread object? > Does thread specific data available? > Does boost::this_thread functions available? > So is there something which f needs from "t" object? > > Thank you in advance! > > Best Regards > > > >

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Connecting Windows Messages/Events with Boost callbacks
by asif saeed 25 Mar '11

25 Mar '11

Hi, I recall sometime back someone posted this question on this list and the response/answer was very good. Could someone please provide link to that earlier post? Or, alternatively, could you please post the solution again? Best regards / Asif

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Re: [Boost-users] Collecting boost multi-index meta data
by Joaquin M Lopez Munoz 25 Mar '11

25 Mar '11

Gokulakannan Somasundaram <gokul007 <at> gmail.com> writes: > > > Hi, > Say i have a boost::tuple / MPL Sequence, on which i have > created a multi-index. Is it possible for me collect all the > attribute numbers on which i have declared the > IndexSpecifierList( the one passed as template parameter to > boost::multi_index::indexed_by ) ? Hi Gokul, I'm not sure I undersand your question. Have you taken a look at the index_type_list nested type? http://www.boost.org/libs/multi_index/doc/reference/multi_index_container.h… types >From this MPL sequence you can easily extract the list of key extractor types used for defining the multi_index_container, which hopefully is close to what you're after. Don't hesitate to elaborate a little more on your question and I'll see whether I can be more helpful. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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Math/Statistical Distributions
by Andrej van der Zee 25 Mar '11

25 Mar '11

Hi, Statistics have been a while ago... I was reading the documentation, at least part of it, of the Boost library Math/Statistical Distributions. But I think I need a bit of help... I have many values Yi that are closely distributed around a mean value Y-mean. The collection of Yi is obtained by an algorithm that sometimes produces trash values that need to be discarded. Such false values are typically not "close" to the Y-mean. I was hoping somebody could tell what distribution I should use and how I should use this. If I recall correctly from my school-days, I need the Normal (Gaussian) Distribution. What would be the algorithm to find those trash values? Thank you, Andrej

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Serialization: multiple definition of 'boost::archive::detail::init_guid...
by Marco Piacentini 25 Mar '11

25 Mar '11

Hi guys...I've found on google some people with the same problem, but all of them have a partial solution... In practice this error happens where I include a .h file which contain the directive #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> and the macro BOOST_CLASS_EXPORT() in more than one .cpp file... I have the necessity to serialize/deserialize in more than one .cpp file and at these points I have to include the .h which contains the polymorphic struct that I have to serialize/deserialize. So the partial solution proposed from others to put all the the include in a single file, is not praticable for me.. Do you know another solution?thank you very much... Bye..

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Boost Threads are not parallel
by Panagiotis Foteinos 25 Mar '11

25 Mar '11

Hello users. I observed the boost threads behave strangely, depending on the way I call the function to be executed in parallel. In the following example (example #1), the threads launched are executed in parallel: **************************************************************************************** 1) class Test { int insert(){}; } object; boost::thread* threads = new boost::thread[N]; for(unsigned int i = 0; i < N; i++) { threads[i] = boost::thread(&Test::insert, &object); } **************************************************************************************** However, in the following example (example #2), the threads are executed sequentially. Only the line in the for-loop body differs from example#1. **************************************************************************************** 2) class Test { int insert(){}; } object; boost::thread* threads = new boost::thread[N]; int ret; for(unsigned int i = 0; i < N; i++) { threads[i] = boost::thread(boost::lambda::var(ret) = object.insert()); } **************************************************************************************** Can anybody explain why the threads in example#2 are executed sequentially (i.e., one at a time)? Best Regards, Panagiotis Foteinos

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io_service::stop() call safe from within post()ed functor?
by Dom Driver 25 Mar '11

25 Mar '11

Hi guys, Picture a server class with the following methods (pseudocode): void Server::Work() { // Start the Async receive. mSocket.async_receive_from( *blah* ) ); // Start the Async IO service. mASIOService.run(); } void Server::Start() { // Launch a new thread to do the work. mThread = boost::thread( boost::bind( &Server::Work, this ) ); } void Server::Stop() { // Post the stop request to the io_service. mASIOService.post( boost::bind( &Server::DoStop, this ) ); // Join the comms thread. mThread.join(); } void Server::DoStop() { // Actually stop the io_service. mASIOService.stop(); } Assuming handling of packets is all correctly implemented, is it safe for the user to simply call the Stop() object method to stop the server? Basically, can a function that's been post()ed to an io_service call io_service.stop() for that io_service? TIA, Dom

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[iostreams] Can I apply different char_type on a chain of filters?
by 甜瓜 25 Mar '11

25 Mar '11

Hi, all, I usually want to read a file, and group the bytes into some object (eg: struct MyData) for further use. boost::iostreams provides the filtering_stream, but it seems all filters along the chain MUST have the same char_type. Is there a way that transform a byte stream into MyData stream? eg: ifstream file("d.gz", ios_base::in | ios_base::binary); filtering_streambuf<input> in; in.push(MyDataExtractor()); in.push(gzip_decompressor()); in.push(file); class MyDataExtractor { public: typedef MyData char_type; struct category ...; template<typename Source> std::streamsize read(Source& src, char_type* s, std::streamsize n) {...} }; Thank you in advance! -- melon

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[BOOST Interprocess] file lock error on MSVC 10
by Claude 24 Mar '11

24 Mar '11

Hi, I'm trying to compile simple program with MSVC++ 10 that use <boost/interprocess/sync/file_lock.hpp> include file (boost version 1.44) But I have a compile error in this file at row 68: C:\Users\Claudio\Desktop\boost_1_44_0\boost/interprocess/sync/file_lock.hpp(68): vedere il riferimento all'istanza del modello di funzione 'boost::interprocess::file_lock &&boost::interprocess::move<boost::interprocess::file_lock&>(T)' in corso di compilazione with [ T=boost::interprocess::file_lock & ] "Impossibile associare un elemento lvalue a un riferimento di rvalue" ("Can not associate a lvalue to a rvalue reference") This program compiles without error on GCC 4.5 (Linux Ubuntu) Why? -- View this message in context: http://boost.2283326.n4.nabble.com/BOOST-Interprocess-file-lock-error-on-MS… Sent from the Boost - Users mailing list archive at Nabble.com.

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Boost gregorian date time from preformated string
by Louis Hoefler 24 Mar '11

24 Mar '11

I use boost 1.46.0 and visual studio 2010. I try to convert a string into a date time object. I found some examples that use stringstreams. Is it possible to convert custom formatted date/time strings into gregorian date objects without using a stringstream? Thank you, Louis

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Re: [Boost-users] Thread Interruption Best Practice
by Dom Driver 24 Mar '11

24 Mar '11

> if I understand your problem you want the thread blocking in select to return? Correct. I need this call to return when: 1) I've got some data waiting to be read. 2) The application is terminating and I want to stop my RX communications thread. The first one is straightforward. I'll investigate the use of pipes as a secondary option. As for 2), from other suggestions, I've gone back to the ASIO library. I read about slushies and brain-freeze, and thought it might be the way to go. However, I think I've managed to fall victim to brainfreeze myself. >From the ASIO example at: http://www.boost.org/doc/libs/1_46_1/doc/html/boost_asio/example/echo/async… This is an asynchronous server similar to what I'm trying to do here. I've got a couple of questions on this, 1) When the server object is created, the call to socket.async_read_from() is made immediately. If there is no data waiting, to be read, this call returns immediately, right? 2) When data does arrive, the handler 'handle_receive_from()' is called. Regardless of whether some bytes are read or not, we eventually call socket.async_read_from() again. This is probably quite fundamental to what I'm misunderstanding, but doesn't this mean I'll be effectively calling socket.async_read_from() from within the handler of a call to socket.async_read_from()? Will I be recursing indefinitely until the application terminates? That doesn't sound right, so I must be missing something very obvious here. Hmmm. Biblical-style ray-of-light guidance appreciated!

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Project using Boost won't build with Xcode 4; complains about "global weak symbols"
by G S 23 Mar '11

23 Mar '11

Hi all. I'm using Boost in an iPhone app as a statically linked lib, and after updating to Xcode 4 the project won't build. It fails with this: *ld: bad codegen, pointer diff in boost::system::error_category:* *:error_category()to global weak symbol vtable for boost::system::error_**categoryfor architecture i386* Happens for both simulator and device, after the same project built fine under previous Xcodes. Anybody have some insight on this and a solution? Thanks! Gavin

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[uBLAS] Matrix creation vs resize
by Ryan 23 Mar '11

23 Mar '11

I need to remove rows from a matrix if it fails a comparison. I have two possible options to remove the matrix rows. Option 1 adds a row to the new matrix for each row from the old matrix that passes the comparison. Option 2 keeps track of the rows from the old matrix that passed the comparison and then creates a new matrix all at once. I'm wondering which option is more efficient or is there a simpler way to achieve the same results? Ryan Option 1 void( matrix<double> const& H, matrix<double> const& P, matrix<double> const& R, vector<double> const& v) { double const rejection_criterion = 2; matrix<double> M = prod(H, matrix<double>(prod(P, trans(H))) + R; matrix<double> result; int matrix_size = 1; for (unsigned i = 0; i < v.size(); ++i) { if ( v[i] * v[i] < rejection_criterion * M(i,i)) { result.resize(matrix_size, H.size2(), true); matrix_row<matrix<double> > oldH (H, i); matrix_row<matrix<double> > newH (result, matrix_size - 1); newH = oldH; matrix_size++; } } } Option 2 void( matrix<double> const& H, matrix<double> const& P, matrix<double> const& R, vector<double> const& v) { double const rejection_criterion = 2; matrix<double> M = prod(H, matrix<double>(prod(P, trans(H))) + R; list<unsigned> goodrows; for (unsigned i = 0; i < v.size(); ++i) { if ( v[i] * v[i] < rejection_criterion * M(i,i)) { goodrows.push_back(i); } } matrix<double> result(goodrows.size(), H.size2()); for ( unsigned i = 0, list<unsigned>::iterator iter = goodrows.begin(); i < result.size1(); ++i, ++iter) { matrix_row<matrix<double> > oldH (H, *iter); matrix_row<matrix<double> > newH (result, i); newH = oldH; } }

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String transformation using string_algo
by Remko Tronçon 23 Mar '11

23 Mar '11

Hi, I want to apply an (un-)escaping transformation on a string (e.g., map "<" to "<", map ">" to "<", ...). I was wondering whether boost string algorithms can provide a good way of doing this or not. I was corsidering find_format, but the problem there is that the finder has to check for occurrence of "<" (by matching a string), but then the formatter needs to check again which of the strings the finder matched ("<", ">") to emit the correct character, which sounds suboptimal. A workaround would be to make the finder always succeed, and let the formatter do the actual check and emit the string if it matches. Is there a better alternative? I also noticed there's a "transform_range_copy", but this isn't documented. thanks! Remko

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any __cxa_demangle / UnDecorateSymbolName in boost ?
by Vial, Florent 23 Mar '11

23 Mar '11

Hi all, i want to retrieve the class name of some std::type_info in my application. is there any function to help me with this within boost ? I looked for it in the boost 1.46.1 code but did not find anything. My problem is that UnDecorateSymbolName is not thread safe under Windows. Thank you in advance, Florent ________________________________ Arnold & Richter Cine Technik GmbH & Co. Betriebs KG Sitz: München - Registergericht: Amtsgericht München - Handelsregisternummer: HRA 57918 Persönlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH Sitz: München - Registergericht: Amtsgericht München - Handelsregisternummer: HRB 54477 Geschäftsführer: Franz Kraus; Dr. Martin Prillmann [http://www.arri.de/fileadmin/mail_images/CTBanner.gif] A new star is born – ALEXA the most versatile digital camera system. Get all the latest information from arridigital.com and YouTube.

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Traversing a graph
by Vipin Varma 23 Mar '11

23 Mar '11

Hi, I have a quick question about graph traversal: what is the appropriate algorithm to be used if I want to find the shortest distance between 2 specified vertices {v_s, v_d} such that every edge on the graph is traversed at least once? I've already used the breadth_first_search() and dijkstras_shortest_paths() for other problems wherein v_s = v_d. Seemingly, these algorithms cannot be used when the source and destination vertices are dissimilar. Thanks, Vipin

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serialization example
by Marco Piacentini 23 Mar '11

23 Mar '11

Hi guys..a very simple question... In the example of the serialization, before serialize, an header is linked to the data. It will be handle both in write and read operations. Is this header essential for the serialization process, or it can be omitted and I can serialize only the data? thank you...

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issues when using boost.bind from boost.thread
by Sean Farrow 23 Mar '11

23 Mar '11

Hi: I'm trying to use boost.bind when starting a thread. The following code starts a thread and tries to pass in a boost.asio.io_service as well. boost::thread* t = new boost::thread(boost::bind(&boost::asio::io_service::run, &io)); I'm getting the following exception when running this code. Unhandled exception at 0x7c812afb in MDRLite.exe: Microsoft C++ exception: boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::system::system_error> > Removing the previous block of code removes the error. Having read the boost.bind, The boost.tread/boost.asio documentation I carn't seem to find what is wrong. This seems to be the final piece of the jigsaw that I carn't seem to crack! Any help appreciated. Cheers Sean.

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[Statechart] Why does this state machine enter unstable state only in debug mode?
by Zhu Bicen 23 Mar '11

23 Mar '11

I am trying to use statechart in a player application. And found a weird issue, so I write following code to reproduce the issue and ask for help. 1. call the MciWndPlay win32API to play a music file within a state entry action 2. Windows msg , which indicate the player current player position, is coming 3. call process_event within Windows procedure 4. but assert failed: get_pointer(pOutermostUnstableState_) == 0 It seems the PlayingState entry action does not execute completely, The debug message after MciWndPlay call is not also printed out, but another event is coming, But This is a single thread application, the MciWndPlay is just Send Message to something and return immediately. I also print out the thread ID, all is the same. Another thing is this assert failure is only occurred in Debug Mode, in release mode all goes well. I am using Visual C++ 2008 express, and boost 1.46.1. Any comments and indication is welcome. I am confused by this issue several days. Thanks in advance. // BugFix.cpp : Defines the entry point for the application. // #include "stdafx.h" #include "BugFix.h" #include "Vfw.h" #include <iostream> #include <boost/statechart/event.hpp> #include <boost/statechart/state_machine.hpp> #include <boost/statechart/simple_state.hpp> #include <boost/statechart/state.hpp> #include <boost/statechart/custom_reaction.hpp> #include <boost/statechart/transition.hpp> #include <boost/statechart/result.hpp> #include <mmsystem.h> #pragma comment(lib, "vfw32.lib") namespace fsm = boost::statechart; #define MAX_LOADSTRING 100 // Global Variables: HINSTANCE hInst; TCHAR szTitle[MAX_LOADSTRING]; TCHAR szWindowClass[MAX_LOADSTRING]; std::wstring file_name = L"D:\\VOA\\5. Deep Six It Is Well Hidden.mp3"; // Forward declarations of functions included in this code module: ATOM MyRegisterClass(HINSTANCE hInstance); BOOL InitInstance(HINSTANCE, int); LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM); INT_PTR CALLBACK About(HWND, UINT, WPARAM, LPARAM); static std::wstring FILE_NAME = L""; struct OpenFileEvent: public fsm::event< OpenFileEvent >{ std::wstring file_name; OpenFileEvent(const std::wstring p_file_name):file_name(p_file_name){} }; struct UpdatePosEvent: public fsm::event< UpdatePosEvent >{ long pos; UpdatePosEvent(long position): pos(position){} }; class WaitingForFileState; class PlayingState; class PlayerFsm : public fsm::state_machine< PlayerFsm, WaitingForFileState > { public: friend class WaitingForFileState; friend class HandlingFileState; friend class PlayingState; }; class WaitingForFileState: public fsm::simple_state< WaitingForFileState, PlayerFsm > { public: typedef fsm::custom_reaction< OpenFileEvent > reactions; fsm::result react( const OpenFileEvent& evt) { std::cout << "OpenFileEvent is received " << std::endl; FILE_NAME = evt.file_name; return transit< HandlingFileState >(); } }; class HandlingFileState: public fsm::state< HandlingFileState, PlayerFsm, PlayingState> { public: HandlingFileState( my_context ctx ): my_base( ctx){ MCIWndOpen(_playerWnd, FILE_NAME.c_str(), NULL); } }; class PlayingState: public fsm::simple_state< PlayingState, HandlingFileState> { public: PlayingState() { std::cout << "Entering PlayingState" << std::endl; std::cout << "fsm threadId = " << GetCurrentThreadId() << std::endl; assert(MCIWndPlay(_playerWnd) == 0); // below message is not printed out in debug mode, // and another message UpdatePosEvent come // and StateChart assert failure std::cout << "After MCIWndPlay" << std::endl; } typedef fsm::custom_reaction< UpdatePosEvent > reactions; fsm::result react( const UpdatePosEvent& evt){ std::cout << "UpdatePosEvent is received in PlayingState" << std::endl; return fsm::detail::result_utility:: make_result( fsm::detail::consumed ); } private: long current_pos_; }; HWND _playerWnd; PlayerFsm _player_fsm; int APIENTRY _tWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { AllocConsole(); freopen("CONOUT$", "w+t", stdout); freopen("CONOUT$", "w+t", stderr); std::cout << "threadId = " << GetCurrentThreadId() << std::endl; UNREFERENCED_PARAMETER(hPrevInstance); UNREFERENCED_PARAMETER(lpCmdLine); // TODO: Place code here. MSG msg; HACCEL hAccelTable; // Initialize global strings LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING); LoadString(hInstance, IDC_BUGFIX, szWindowClass, MAX_LOADSTRING); MyRegisterClass(hInstance); // Perform application initialization: if (!InitInstance (hInstance, nCmdShow)) { return FALSE; } hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_BUGFIX)); // Main message loop: while (GetMessage(&msg, NULL, 0, 0)) { if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg)) { TranslateMessage(&msg); DispatchMessage(&msg); } } return (int) msg.wParam; } ATOM MyRegisterClass(HINSTANCE hInstance) { WNDCLASSEX wcex; wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = CS_HREDRAW | CS_VREDRAW; wcex.lpfnWndProc = WndProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = hInstance; wcex.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_BUGFIX)); wcex.hCursor = LoadCursor(NULL, IDC_ARROW); wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); wcex.lpszMenuName = MAKEINTRESOURCE(IDC_BUGFIX); wcex.lpszClassName = szWindowClass; wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL)); return RegisterClassEx(&wcex); } BOOL InitInstance(HINSTANCE hInstance, int nCmdShow) { HWND hWnd; hInst = hInstance; // Store instance handle in our global variable hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL); if (!hWnd) { return FALSE; } ShowWindow(hWnd, nCmdShow); UpdateWindow(hWnd); return TRUE; } LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) { int wmId, wmEvent; PAINTSTRUCT ps; HDC hdc; switch (message) { case WM_COMMAND: wmId = LOWORD(wParam); wmEvent = HIWORD(wParam); // Parse the menu selections: switch (wmId) { case IDM_ABOUT: _player_fsm.process_event(OpenFileEvent(file_name)); //DialogBox(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About); break; case IDM_EXIT: DestroyWindow(hWnd); break; default: return DefWindowProc(hWnd, message, wParam, lParam); } break; case WM_CREATE: _player_fsm.initiate(); _playerWnd = MCIWndCreate( hWnd, hInst, MCIWNDF_NOTIFYPOS|MCIWNDF_NOMENU|MCIWNDF_NOTIFYMODE, NULL); break; case MCIWNDM_NOTIFYPOS: std::cout << "received MCIWNDM_NOTIFYPOS msg, threadId = " << GetCurrentThreadId() << std::endl; _player_fsm.process_event(UpdatePosEvent(lParam)); break; case WM_PAINT: hdc = BeginPaint(hWnd, &ps); EndPaint(hWnd, &ps); break; case WM_DESTROY: PostQuitMessage(0); break; default: return DefWindowProc(hWnd, message, wParam, lParam); } return 0; } -- Best Regards Bicen Zhu

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Boost.Test: test suite with parameter
by Hendrik Fuß 23 Mar '11

23 Mar '11

Hi folks, I've got a suite of tests that test the functions of an abstraction layer. What I would like to do is to apply this suite to any number of concrete implementations of the abstract interface. That is, my test suite should have one parameter, say, a pointer to the abstract interface's implementation. I know I can register unary function based test cases, but how can I provide an argument to an entire test suite? I wasn't able to figure this out. Appreciate any help. cheers Hendrik

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boost::python::return_value_policy<bp::reference_existing_object>() is weakref in python?
by Thomas Rab 23 Mar '11

23 Mar '11

I've used boost::python in the past, but this problem has me stumped. Here's part of the class I'm having issues with: class Entity { public: Entity(); ~Entity(); //Call to check our collider against all entities that have "tag" Collider* Collide(const std::string &tag); }; and here is the boost::python code: bp::class_< Entity_wrapper >( "Entity", bp::init< >() ) .def( "Collide" , (::Monocle::Collider * ( ::Monocle::Entity::* )( ::std::string const & ) )( &::Monocle::Entity::Collide ) , ( bp::arg("tag") ), bp::return_value_policy<bp::reference_existing_object>() ) In python if I do something like this: collider = entity.Collision("Paddle") collider is a weakref to 'type' Not a Collider. My other functions that return pointers seem to be fine. Is it just the call policy I'm using? What Collide does is call a static function ("Collide") of the Collision class, which in turn returns a Collider* on success and NULL otherwise. Any help would be appreciated! If you need anymore information, let me know! -- Tom Rab

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[boost::thread] lib broken in trunk for Win32
by teajay 22 Mar '11

22 Mar '11

Hello, I just noticed that the thread lib build for win32 is broken due to a superfluous #if on line 14 in the file tss_pe.cpp. Regards, Thomas Bernard

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[context review] Review - alternative version available
by Oliver Kowalke 22 Mar '11

22 Mar '11

Hi, I've uploaded an alternative version to boost vault (boost.context-alternative_version.zip : http://tinyurl.com/6fpnkro) The documentation is available at http://ok73.ok.funpic.de/alternative/boost/libs/context/doc/html/. changes: - fixed bug for x86_64/sysv/elf assembler file: missing assembler directive .type added - as suggested by Artyom and Vicente: - assembler implementation and native implementation of context switching functions compiled and applied as template arg to context<> -> context<> == context< protected_stack, asm_impl > on UNIX, context< protected_stack, native_impl > on Windows - for Windows assembler implementation is disabled Oliver

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[StateChart] How to pass arguments to a state constructor when doing state transition?
by Zhu Bicen 22 Mar '11

22 Mar '11

Hi all, I have a state like this, which has two parameters in it's constructor except the ctx. I want to know how to pass these two arguments to the constructor, when do state transition? I have tried this: transit< RepeatedPlayingState , 1, 2>(); But it cause compiling error? How to do this? I want to pass something to a new entered state. Thanks! class RepeatedPlayingState: public state< RepeatedPlayingState, PlayingState > { public: RepeatedPlayingState( my_context ctx , long start_pos, long end_pos) : my_base( ctx ){ context< PlayerFsm >().player_.PlayFromTo(start_pos, end_pos); } }; Best Regards Hill

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Re: [Boost-users] compilation error, please help
by Steven Watanabe 22 Mar '11

22 Mar '11

AMDG On 03/22/2011 09:59 AM, kovari andris wrote: > I have version 4.4.5 > I think the latest That wasn't what I was asking. g++ -v gives all the information about how the compiler was configured. In Christ, Steven Watanabe

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Re: [Boost-users] compilation error, please help
by Steven Watanabe 22 Mar '11

22 Mar '11

AMDG On 03/22/2011 08:42 AM, kovari andris wrote: > to the greater glory of God... > I did try some variations of g++ -pthread... > > but did not work. > I got all sorts of suggestions on different forums, but it gives the same error. All right. What does g++ -v say? In Christ, Steven Watanabe

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compilation error, please help
by kovari andris 22 Mar '11

22 Mar '11

Hi folks, I have: installed eclipse on ubuntu 10.10 installed libbost 1.4 using sinaptic pkg manager started a simple new c++ project, #include <boost/thread.hpp> int main(int argc, char* arg[]){ } I tried to build it, and had the error: Invoking: GCC C++ Compiler g++ -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"main.d" -MT"main.d" -o"main.o" "../main.cpp" In file included from /usr/include/boost/thread/detail/platform.hpp:17, from /usr/include/boost/thread/thread.hpp:12, from /usr/include/boost/thread.hpp:13, from ../main.cpp:8: /usr/include/boost/config/requires_threads.hpp:47: error: #error "Compiler threading support is not turned on. Please set the correct command line options for threading: -pthread (Linux), -pthreads (Solaris) or -mthreads (Mingw32)" In file included from /usr/include/boost/thread/thread.hpp:12, from /usr/include/boost/thread.hpp:13, from ../main.cpp:8: /usr/include/boost/thread/detail/platform.hpp:67: error: #error "Sorry, no boost threads are available for this platform." In file included from /usr/include/boost/thread.hpp:13, from ../main.cpp:8: /usr/include/boost/thread/thread.hpp:19: error: #error "Boost threads unavailable on this platform" blablabla...so on... a lot more errors. what am I missing here? I dont understand the error message, and tried to write -pthread wherever I could, but did not work. Any tips? detailed or stepbystep solution please, because I am a beginner, and dont understand chinese:) thank you guys

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newbie fail: Too many levels of symbolic link
by Gary Pajer 22 Mar '11

22 Mar '11

I have a c++ shared library, and I'd like to use the classes and functions in python. So I'm trying boost.python. I'm on Ubuntu 10.10, and I've downloaded the boost tarball. I think I've followed the instructions here<http://www.boost.org/doc/libs/1_46_1/libs/python/doc/building.html>and (more to the point) here<http://www.boost.org/doc/libs/1_46_1/more/getting_started/unix-variants.htm…>to the letter. But when I execute "sudo ./bjam" I get dozens upon dozens of failures. For example, "g++" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -pthread -DBOOST_ALL_NO_LIB=1 -DBOOST_PYTHON_SOURCE -DBOOST_PYTHON_STATIC_LIB -DNDEBUG -I"." -I"/usr/include/python2.6" -c -o "bin.v2/libs/python/build/gcc-4.4.5/release/link-static/threading-multi/numeric.o" "libs/python/src/numeric.cpp" ...failed gcc.compile.c++ bin.v2/libs/python/build/gcc-4.4.5/release/link-static/threading-multi/numeric.o... gcc.compile.c++ bin.v2/libs/python/build/gcc-4.4.5/release/link-static/threading-multi/list.o In file included from ./boost/python/detail/config.hpp:15, from ./boost/python/detail/prefix.hpp:14, from ./boost/python/list.hpp:8, from libs/python/src/list.cpp:5: ./boost/config.hpp:35: fatal error: ./boost/boost/config/compiler/gcc.hpp: Too many levels of symbolic links compilation terminated. The file references are different, but the error is always the same. What have I done wrong? thanks, gary_p

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[asio] What have to be done to receive UDP broadcast packets?
by Michael Schulze 22 Mar '11

22 Mar '11

Hi list, I struggle with setting up an asio udp socket on Linux that is able to receive broadcasts. I managed the sending of broadcasts, but receiving seems to have a problem. I also managed sending and receiving of broadcasts with the native socket api of Linux. However, in the project we use asio to have portability across platforms and therewith we need to receive broadcast with asio too. The question is: How should an asio udp socket be setup in order to receive broadcasts? I did the following: udp::socket socket(io_service); socket.open(udp::v4()); boost::asio::socket_base::broadcast option(true); socket.set_option(option); socket.bind(udp::endpoint(address_v4::any(),8888)); and then I started receive_from. What is wrong with this? I did not receive the sent broadcast. Regards, Michael

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Cannot dlclose() module when including exception_ptr.hpp in GCC 4.5
by ichramm 22 Mar '11

22 Mar '11

Hi I'm having and issue with boost and gcc 4.5, I'm posting here before posting in the gcc mailing list 'cause it only happends if using boost. Thre following problem was tested with boost 1.44 and boost 1.46 (single and multi threaded) Situation: - Environment with GCC 4.5.2 (kernel 2-6-36 and 4.6.37, glibc 2.11 and 2.12 - C application that loads/unloads dynamic modules using dlopen/dlclose - C++ dynamic module compiled/linked agans boost::thread, and including <boost/exception_ptr> Problem: - dlclose() always returns zero, so the module is never unloaded Including <boost/thread/thread.hpp> or any other boost header works fine This only happends with GCC 4.5, so it could be a problem related to gcc, but I dnot know it yet. I'm attanching 3 small test files, so you can check if this happens on your machine, just execute 'make run' After reading the test application you say 'remove the while loop!', but the right behavior is that the second call to dlclose() should fail with 'shared object ot open'. Thanks in advance -- Saludos! :wq PS: Escuse my poor english :P

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[asio] recommended way of handling unix signals ?
by Avi Bahra 22 Mar '11

22 Mar '11

I have been looking at the boost asio 1.45 docs but there is no mention of signal handling ? Is this is a known deficiency of asio, or are there any any recommended ways of handling signals in a asio server ? Best regards, Ta, Avi

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boost::asio close TCP connection cleany
by Marco Piacentini 22 Mar '11

22 Mar '11

Hy..I've seen in the tutorial that client side disconnect is called simply by a break in the read loop. I would like to know which is the step-by-step instruction to close correctly a TCP connection (both server and client side) and where I have to put them. I've seen the close and shutdown functions, but I don't know where call them. Finally...what I can do when an EOF error happens?? thank you..

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RegEx - Exception on faulty RE, or other report of failure.
by Kerry, Richard 22 Mar '11

22 Mar '11

Using Boost Regex for the first time I note that if there is an error in the syntax of the RE given then an exception is raised. Is this the only way of checking the RE syntax ? Or is there a function that I can call which can validate it for me without an exception. I don't see anything in the documentation (I'm using Boost 1.4 as I need to use it with Visual C++ 6). Regards, Richard. Richard Kerry BNCS Engineer Siemens IT Solutions and Services Ltd The Business Technologists Room 457 Drama Building, BBC Television Centre, Wood Lane, London, W12 7RJ T: +44 (0)20 82259063 F: +44 (0)20 8576 8182 M: +44 (0)7921 244993 Email: richard.kerry(a)siemens.com<blocked::mailto:richard.kerry@siemens.com> Website: www.siemens.co.uk/it-solutions<blocked::outbind://47/www.siemens.co.uk/it-solutions> This e-mail contains confidential information and is for the exclusive use of the addressee/s. If you are not the addressee, then any distribution, copying or use of this e-mail is prohibited. If received in error, please advise the sender and delete it immediately. We accept no liability for any loss or damage suffered by any person arising from use of this e-mail. Siemens IT Solutions and Services Limited Registered No: 1203466 England Registered Office: Faraday House, Sir William Siemens Square, Frimley, Camberley, GU16 8QD

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Boost - How does VC know what to link ?
by Kerry, Richard 22 Mar '11

22 Mar '11

Can someone explain (*) how Visual Studio gets to know which lib file to link with ? I see an entry (Auto-Linking under point 6 on the Getting Started page) which says that it does this, but I'd like to know how. I want to be sure that once I've started using Boost in a project then any of my colleagues building the same project will get the libraries pice-up properly. (*) or point me to the code that does it. Is is some sort of compiler directive that controls it ? It's Visual Studio 6 that I'm using, but I expect it's the same for others. Richard Kerry BNCS Engineer Siemens IT Solutions and Services Ltd The Business Technologists Room 457 Drama Building, BBC Television Centre, Wood Lane, London, W12 7RJ T: +44 (0)20 82259063 F: +44 (0)20 8576 8182 M: +44 (0)7921 244993 Email: richard.kerry(a)siemens.com<blocked::mailto:richard.kerry@siemens.com> Website: www.siemens.co.uk/it-solutions<blocked::outbind://47/www.siemens.co.uk/it-solutions> This e-mail contains confidential information and is for the exclusive use of the addressee/s. If you are not the addressee, then any distribution, copying or use of this e-mail is prohibited. If received in error, please advise the sender and delete it immediately. We accept no liability for any loss or damage suffered by any person arising from use of this e-mail. Siemens IT Solutions and Services Limited Registered No: 1203466 England Registered Office: Faraday House, Sir William Siemens Square, Frimley, Camberley, GU16 8QD

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[autolink] for gcc?
by alfC 22 Mar '11

22 Mar '11

Hi, I recently discovered boost/auto_link.hpp which besides the comment in the source file doesn't seem to be documented. The question is, can it be used with gcc c++? if not, is there an alternative? Thank you, Alfredo

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[asio] deadline_timer not waiting properly?
by Dylan Klomparens 22 Mar '11

22 Mar '11

Hello, I tried using the boost deadline_timer in this simple test application, but had some trouble. The goal is for the timer to trigger every 45 milliseconds using the "expires_at()" member function of the deadline_timer. (I need an absolute time, so I'm not considering expires_from_now(). I am also not concerned about drift at the moment). When I run the program, wait() does not wait for 45 ms! Yet, no errors are reported. Am I using the library incorrectly somehow? -- Dylan Sample program: #include <boost/asio.hpp> #include <boost/thread.hpp> #include <boost/bind.hpp> #include <boost/date_time/posix_time/posix_time.hpp> #include <iostream> using namespace std; int main() { boost::asio::io_service Service; boost::shared_ptr<boost::thread> Thread; boost::asio::io_service::work RunForever(Service); Thread = boost::shared_ptr<boost::thread>(new boost::thread(boost::bind(&boost::asio::io_service::run, &Service))); boost::shared_ptr<boost::asio::deadline_timer> Timer(new boost::asio::deadline_timer(Service)); while(1) { boost::posix_time::time_duration Duration; Duration = boost::posix_time::microseconds(45000); boost::posix_time::ptime Start = boost::posix_time::microsec_clock::local_time(); boost::posix_time::ptime Deadline = Start + Duration; boost::system::error_code Error; size_t Result = Timer->expires_at(Deadline, Error); cout << Result << ' ' << Error << ' '; Timer->wait(Error); cout << Error << ' '; boost::posix_time::ptime End = boost::posix_time::microsec_clock::local_time(); (cout << "Duration = " << (End - Start).total_milliseconds() << " milliseconds" << endl).flush(); } return 0; }

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boost binary_iarchive compiler error converting from side_t to streamsize
by Liron Kopinsky 21 Mar '11

21 Mar '11

Hi all, I'm having a problem were, when I #include <boost/archive/binary_iarchive.hpp>, it says that there is an error converting from size_t to std::streamsize. This seems to come from basic_binary_iprimitive.hpp line 181 because std::memcpy takes a size_t but it's passing in a std::streamsize. This seems to just be a warning, but even though I added #pragma warning(disable : 4244) and my compiler still isn't happy and gives this output: http://boost.codepad.org/faSZmjNM We seem to only have this problem when we're building in VS2010, but it works fine in 2005. Any help would be appreciated. Thanks, Liron Kopinsky Image Metrics Software Developer liron.kopinsky(a)image-metrics.com

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Boost Concept Library - fusion and other libraries
by Robert Ramey 21 Mar '11

21 Mar '11

Lately I've been exploring boost/fusion for a project which I have been thinking about for 25 years. I believe that this might be the tool to do what I want. In the course of my experiments with this library and it's associated documentation, I've been interested in understanding the libraries "concepts" (e.g. AssociativeSequence, etc) and the relationship if any to the boost concept library. To try to be more clear, when I see something in the documentation like "AssociativeSequence", I'm sort of hoping/expecting to write into my code something like template<typename S> struct my_type { ... BOOST_CONCEPT_ASSERT(( <AssociativeSequence<S> > )); ... }; But it seems that I can't do this. Why is this? a) Can I indeed write something like this if I include some specific headers that I haven't found? b) Should I be using some other concept checker such as something in MPL c) Am I wrong about thinking that it would be useful to have this? That is, is there some reason why I shouldn't expect to find this? In poking around, I don't find a lot I'm expecting to find. For example, I'm sort of expecting to find: boost::std::concepts { ... concept checking classes for STL } and something similar for all or most of the libraries who make extensive usage of "concepts" in their documentation. When I so grep for files which contain BOOST_CONCEPT (to catch BOOST_CONCEPT_ASSERT, etc.. I get the following: bash-3.2$ pwd /cygdrive/c/BoostRelease/boost bash-3.2$ grep -l BOOST_CONCEPT * */*.hpp concept_archetype.hpp concept_check.hpp concept/assert.hpp concept/requires.hpp concept/usage.hpp concept_check/borland.hpp concept_check/general.hpp concept_check/has_constraints.hpp concept_check/msvc.hpp graph/bron_kerbosch_all_cliques.hpp graph/buffer_concepts.hpp graph/graph_concepts.hpp graph/graphviz.hpp graph/metric_tsp_approx.hpp graph/stoer_wagner_min_cut.hpp graph/tiernan_all_cycles.hpp graph/transitive_reduction.hpp icl/closed_interval.hpp icl/continuous_interval.hpp icl/discrete_interval.hpp icl/interval_base_map.hpp icl/left_open_interval.hpp icl/map.hpp icl/open_interval.hpp icl/right_open_interval.hpp iterator/iterator_concepts.hpp range/concepts.hpp bash-3.2$ which suggests to me that this idea is only implemented in graph, icl, iterator and range libraries. Is there a reason for this, or is that it just hasn't been done. If it's the latter, is there a reason I don't see anyone on the requesting that libraries include concept checking classes. Also, reviewers don't seem to mention the lack of these classes in the code - though they complain about it if it's missing from the documentation. After sort of struggling with the whole concept concept, I'm think I'm coming to appreciate it's utility and maybe it's necessity. But given that no one seems to miss it in the boost libraries, I'm concerned that I'm still not getting it. Robert Ramey

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Re: [Boost-users] [boost::thread] interrupt a future get boost::unknown_exception
by 乔志强 21 Mar '11

21 Mar '11

It is only boost::thread int foo() { this_thread::sleep(seconds(1000)); return 0; } int main(int argc, char** argv) { boost::packaged_task<int> pt(&foo); boost::unique_future<int> fi = pt.get_future(); .......................... > > ------------------------------ > > Message: 2 > Date: Fri, 18 Mar 2011 16:43:54 +0100 > From: Viatcheslav.Sysoltsev(a)h-d-gmbh.de > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] [boost::thread] interrupt a future get > boost::unknown_exception > Message-ID: <op.vsjpzgww5q4lf0@pc-sysolts-zdmf> > Content-Type: text/plain; charset=utf-8; format=flowed; delsp=yes > > On Fri, 18 Mar 2011 11:30:11 +0100, ??? <qiaozhiqiang(a)leadcoretech.com> > wrote: > > > [Windows XP, VC++ 10, boost 1.46] > > When interrupt a future, the future.get() throw boost::unknown_exception, > > Not boost::thread_interrupted. > > > > Class boost::thread_interrupted should have a base class for > > current_exception_impl() to catch it ? or use BOOST_THROW_EXCEPTION in > > interruptible_wait) ? > > > > > > /////////////// > > namespace boost > > { > > class thread_interrupted > > {}; > > } > > > > > > exception_ptr current_exception_impl() > > { > > try > > { > > throw; > > } > > catch( > > exception_detail::clone_base & e ) > > { > > return exception_ptr(e.clone()); > > } > > ................ > > catch( > > std::exception & e ) > > { > > return > > exception_detail::current_exception_unknown_std_exception(e); > > } > > catch( > > boost::exception & e ) > > { > > return > > exception_detail::current_exception_unknown_boost_exception(e); > > } > > catch( > > ... ) > > { > > return > > exception_detail::current_exception_unknown_exception(); > > } > > > > > > // unknown_exception////////////////// > > ERROR: Throw in function (unknown) > > Dynamic exception type: class boost::exception_detail::clone_impl<class > > boost::unknown_exception> > > std::exception::what: Unknown exception > > > > > > > > //code ///////////////////// > > #include <boost/thread.hpp> > > #include <boost/date_time/posix_time/posix_time_types.hpp> > > #include <boost/thread/future.hpp> > > using namespace boost::posix_time; > > using namespace boost; > > > > int main(int argc, char** argv) > > { > > boost::packaged_task<int> pt( > > [=]()->int > > { > > this_thread::sleep(seconds(1000)); > > return 0; > > } > > ); > > boost::unique_future<int> fi = pt.get_future(); > > boost::thread task(std::move(pt)); // launch task on a thread > > > > task.interrupt(); > > > > try > > { > > int v = fi.get(); > > } > > catch (boost::exception& exc) > > { > > std::cerr << "ERROR: " << boost::diagnostic_information(exc) << > > std::endl; > > } > > } > > Wow, boost-1.46 and lambdas, you're really working on the edge. Just to be > sure it is a boost problem - can you make a classical function instead > lambda and try with it? The test case seems nearly like one from the > futures example - I really doubt it is a boost problem. > I'd be glad to experiment with it yourself but my latest ubuntu has only > gcc 4.4.5 and the lambdas said to be supported first from 4.5, plus I'd > need to build 1.46 first, which takes quite a time on my nearly-netbook.. > > -- Slava > >

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mpl and set of maps
by Peter Foelsche 21 Mar '11

21 Mar '11

It looks like two maps with the same entries but different ordering are considered different. I'm trying to create a set of maps and I'm inserting two maps. Both maps are identical but the order in which the items were inserted into the map is different. I was thinking that an associative sequence like set is using is_same to compare two elements and I tried to overload is_same -- but this did not work. See code below or attached. #include <boost/mpl/set.hpp> #include <boost/mpl/map.hpp> #include <boost/mpl/bool.hpp> #include <boost/mpl/long.hpp> #include <boost/mpl/for_each.hpp> #include <boost/mpl/insert.hpp> #include <iostream> ? struct print { template<typename T> void operator()(const T &_r) const { //std::cout << typeid(T).name() << "\n"; (*this)(_r, typename boost::mpl::is_sequence<T>::type()); } template<typename T> void operator()(const T &, const boost::mpl::true_ &) const { std::cout << "(\n"; boost::mpl::for_each<T>(print()); std::cout << ")\n"; } template<typename T0, typename T1> void operator()(const boost::mpl::pair<T0, T1> &, const boost::mpl::false_ &) const { std::cout << "pair(" << typeid(T0).name() << ", " << typeid(T1).name() << ")" << "\n"; } template<typename T> void operator()(const T &, const boost::mpl::false_ &) const { std::cout << typeid(T).name() << "\n"; } }; namespace boost { //namespace type_traits //{ //template<typename T0, typename T1> //struct is_same; ? using boost::mpl::map; using boost::mpl::true_; using boost::mpl::insert; ? template<typename T0, typename T1> struct is_same<map<T0, T1>, map<T1, T0> > { typedef boost::mpl::true_ type; }; ? template<typename T0, typename T1, typename T2> struct is_same<map<T0, T1, T2>, map<T2, T1, T0> > { typedef boost::mpl::true_ type; }; ? template<typename T0, typename T1, typename T2> struct is_same<map<T0, T1, T2>, map<T1, T2, T0> > { typedef boost::mpl::true_ type; }; ? template<typename T0, typename T1, typename T2> struct is_same<map<T0, T1, T2>, map<T0, T2, T1> > { typedef boost::mpl::true_ type; }; ? template<typename T0, typename T1, typename T2> struct is_same<map<T0, T1, T2>, map<T1, T0, T2> > { typedef boost::mpl::true_ type; }; //} } int main(int argc, char **argv) { using boost::mpl::long_; using boost::mpl::for_each; using boost::mpl::set; using boost::mpl::map; using boost::mpl::pair; using boost::mpl::insert; typedef long_<0> zero; typedef long_<1> one; typedef long_<2> two; typedef pair< zero, one > zero_2_one; typedef pair< one, one > one_2_one; for_each< insert< insert< set<>, insert< insert< map<>, zero_2_one >::type, one_2_one >::type >::type, insert< insert< map<>, one_2_one >::type, zero_2_one >::type >::type >(print()); return 0; }

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issue with make_shared
by Sean Farrow 21 Mar '11

21 Mar '11

Hi: Ok, having got to grips with fusion, and thought it was working. I now have an issue whereby when using make_shared, it is working in one case, and not in the other. I've got the following definition:P typedef boost::fusion::vector<PmStream*, MIDIInputThread, boost::shared_ptr<boost::asio::io_service> , boost::shared_ptr<boost::thread> > InputType; and when I use: InputType NewInput =InputType(Port, cl, boost::make_shared<boost::asio::io_service> , boost::make_shared<boost::thread>(boost::bind(&boost::asio::io_service::run, io.get()))); Replacing the asio::io declaration with an actual variable of type boost::shared_ptr<boost::asio::io_service> seems to work fine. Is ther anything I'm doing wrong that's not allowing me to use boost::make_shared? Any help appreciated. Regards Sean.

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refering to objects when constructing a boost::fusion::vector
by Sean Farrow 21 Mar '11

21 Mar '11

Hi list: I'm in the process of using boost::fusion::vector, with the following definition: typedef boost::fusion::vector<PmStream*, MIDIInputThread, boost::shared_ptr<boost::asio::io_service>, boost::shared_ptr<boost::thread> > InputType; I'm then constructing this using the following code: PmStream* Port; MIDIInputThread cl; InputType NewInput =InputType(Port, cl, boost::make_shared<boost::asio::io_service>, boost::make_shared<boost::thread>(boost::bind(&boost::asio::io_service::run, io.get()))); What I'm wondering is is there a way to refer to a previously declared argument in this case, I'd like to refer to the shared pointer containing the boost::asio::io_service. Given that I've not actually named this argument, could I use anything from either boost.fusion or boost.mpl to do what I require. Any help appreciated. Regards Sean.

3 2

storing a boost.thread in a boost shared ptr
by Sean Farrow 21 Mar '11

21 Mar '11

Hi: I'm trying to store a boost.thread in a boost::fusion::vector, and need to use a shared ptr, due to boost.thrad being non-copyable I'm using Microsoft visual c++ 2010. I get the following error: 1>d:\devexpress\mdrlite\mdrlite\mdrlite\midiwidget.cpp(21): error C2664: 'boost::shared_ptr<T>::shared_ptr(boost::shared_ptr<T> &&)' : cannot convert parameter 1 from 'boost::_bi::bind_t<R,F,L>' to 'boost::shared_ptr<T> &&' with [ T=boost::thread ] and [ R=size_t, F=boost::_mfi::mf0<size_t,boost::asio::io_service>, L=boost::_bi::list1<boost::_bi::value<boost::asio::io_service *>> ] and [ T=boost::thread ] Reason: cannot convert from 'boost::_bi::bind_t<R,F,L>' to 'boost::shared_ptr<T>' with [ R=size_t, F=boost::_mfi::mf0<size_t,boost::asio::io_service>, L=boost::_bi::list1<boost::_bi::value<boost::asio::io_service *>> ] and [ T=boost::thread ] No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called My boost thread is defined as: boost::thread t(boost::bind(&boost::asio::io_service::run, io.get())); and io is defined as: boost::shared_ptr<boost::asio::io_service> io; I'm obviously overlooking something, I just carn't work out what? Any help appreciated. Regards Sean.

4 5

[context review] Review starts today, Mars 21st 2011
by Vicente BOTET 21 Mar '11

21 Mar '11

Hi all, The review of Oliver Kowalke Context library starts today Mars 21st 2011, and will end on Mars 30th. Boost.Context is a basic building block library that is used for more higher abstractions. It is used by Boost.Fiber, Boost.Tasklet and Boost.Task from the same author. I really hope to see your vote and your participation in the discussions on the Boost DEVELOPMENT mailing lists! WARNING !!!!!!!!!!!!! Only on the Boost DEVELOPMENT mailing lists Please use [context review] as prefix of your post to make easier the review follow up. You can download a frozen version for the review from the Vault, TinyURL: http://tinyurl.com/5r77rel or The documentation is available directly here: http://ok73.ok.funpic.de/boost/libs/context/doc/html/ --------------------------------------------------- About the library: Boost.Context provides a possibility to switch between different user-level context and is intended to be the basis for a higher abstraction like coroutine and fiber. A user-level context represents the current execution state, including all registers and CPU flags, the instruction pointer, the stack pointer. boost::context encapsulates such a user-level context and is able to store/restore its associated user-level context. This allows multiple execution paths running on a single thread using a sort of cooperative scheduling (in contrast a thread is preemptively scheduled) - the running boost::context decides explicitly when its yields to allow another boost::context to run (user-level context switching). A context can only run on a single thread at any point in time but may be migrated between thread. A context switch between threads costs usually thousands of CPU cycles on x86 compared to a user-level context switch with few hundreds of cycles. Boost.Context differes to setjmp()/longjmp() in the fact that the C99 standard does not require that longjmp() preserves the current stack frame, e. g. jumping into a function which was exited via a call to longjmp() is undefined. Boost.Context allows to select the mechanism provided by the operating system (ucontext on UNIX, Windows Fibers on Windows) or a faster implementation provided by this library (fcontext using assembler). --------------------------------------------------- Please always state in your review, whether you think the library should be accepted as a Boost library! Additionally please consider giving feedback on the following general topics: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With what compiler? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? Have a good review, Vicente Review Manager

5 5

[Fusion] value_at_c and its relatives not applicable to Associative Sequence?
by TONGARI 21 Mar '11

21 Mar '11

Hi, the document says that 'value_at_c' accepts a Forward Sequence, and set/map, which is of Associative Sequence as well as Forward Sequence, why the following does not work? #include <boost/fusion/include/value_at.hpp> #include <boost/fusion/include/set.hpp> int main() { namespace fs = boost::fusion; typedef fs::result_of::value_at_c<fs::set<int>, 0> >::type type; return 0; }

3 5

Re: [Boost-users] using boost.asio with wx widgets
by Marat Abrarov 21 Mar '11

21 Mar '11

Hi, Sean Farrow. I use Boost.Asio with Qt. I don't use the default MSVS C++ project structure with additional header, where MSVS adds some preprocessor directives by default. So I moved those directives (preprocessor defines) to project settings: WIN32 WIN32_LEAN_AND_MEAN WINVER=0x0500 _WIN32_WINNT=0x0500 _WIN32_WINDOWS=0x0410 _WIN32_IE=0x0600 May be would solve your problem? Regards, Marat Abrarov.

1 0

Thread Interruption Best Practice
by Dom Driver 21 Mar '11

21 Mar '11

Hi List, I'm fairly new to boost, and have recently started to use the threading system from v1.46 in an app I'm writing targeting Linux. This was primarily to enable execution of threads to be blocked until a condition variable is set, at which point the thread is kicked awake and actions whatever is waiting to be done. All good, and all working as expected. However, I've got another thread which sits listening for data on a socket using a Linux select() call. This blocks until data is available for reading, at which point it is read from the socket as expected. This also works fine, except on termination of the application. Using native Linux implementations, a signal can be sent to the thread that is blocking on the select() call, at which point the call returns, and the EINTR error is set. I can therefore check for this condition and handle appropriately. Is there a way to send a Linux signal (or boost equivalent) to a specific boost thread to emulate this behaviour? Failing that, is there an alternative implementation of the classic Linux select()/read() functionality using boost classes? I had a look at the async I/O library and it seems a bit convoluted. TIA, Dom

3 2

Re: [Boost-users] [boost::thread] interrupt a future get boost::unknown_exception
by 乔志强 21 Mar '11

21 Mar '11

It may be a bug of the thread or future. in boost_1_46_0/doc/html/thread/synchronization.html these Member functions: shared_future class template: Member function get() Member function wait() Member function timed_wait() and unique_future class template: Member function get() Member function wait() Member function timed_wait() Throws: ........ boost::thread_interrupted if the result associated with *this is not ready at the point of the call, and the [current] thread is interrupted. ............ the [current] thread is interrupted. Should be the [working] thread is interrupted ? > > [Windows XP, VC++ 10, boost 1.46] > > When interrupt a future, the future.get() throw boost::unknown_exception, > > Not boost::thread_interrupted. > > > > Class boost::thread_interrupted should have a base class for > > current_exception_impl() to catch it ? or use BOOST_THROW_EXCEPTION to throw ? ////////// namespace boost { class thread_interrupted {}; } These function use [ throw thread_interrupted(); ] : this_thread ::interruption_point() // pthread / win32 this_thread::interruptible_wait() // win32 interruption_checker:: check_for_interruption()// pthread ///////////// // [Windows XP, VC++ 10, boost 1.46] #include <boost/thread.hpp> #include <boost/date_time/posix_time/posix_time_types.hpp> #include <boost/thread/future.hpp> using namespace boost::posix_time; using namespace boost; int foo() { this_thread::sleep(seconds(1000)); return 0; } int main(int argc, char** argv) { boost::packaged_task<int> pt(&foo); boost::unique_future<int> fi = pt.get_future(); boost::thread task(std::move(pt)); // launch task on a thread task.interrupt(); try { int v = fi.get(); } catch (boost::exception& exc) { std::cerr << "ERROR: " << boost::diagnostic_information(exc) << std::endl; } } > > > > // unknown_exception////////////////// > > ERROR: Throw in function (unknown) > > Dynamic exception type: class boost::exception_detail::clone_impl<class > > boost::unknown_exception> > > std::exception::what: Unknown exception

1 0

[function] Compiler error with Boost 1.46.1
by Boris Schaeling 20 Mar '11

20 Mar '11

The sample program at http://en.highscore.de/cpp/boost/src/3.4.3/main.cpp can't be compiled anymore with Boost 1.46.1 (using VC++ 2010). Is this a known problem? 1>------ Rebuild All started: Project: Test, Configuration: Debug Win32 ------ 1> main.cpp 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2668: 'boost::mem_fn' : ambiguous call to overloaded function 1> c:\boost\include\boost-1_46_1\boost\bind\mem_fn_cc.hpp(25): could be 'boost::_mfi::mf1<R,T,A1> boost::mem_fn<void,world,std::ostream&>(R (__thiscall world::* )(A1))' 1> with 1> [ 1> R=void, 1> T=world, 1> A1=std::ostream & 1> ] 1> c:\program files (x86)\microsoft visual studio 10.0\vc\include\xxmem_fn(32): or 'std::tr1::_Mem_fn2<_Rx,_Pmf,_Arg0,_Arg1> std::tr1::mem_fn<void,world,std::ostream&>(_Rx (__thiscall world::* )(_Arg1))' [found using argument-dependent lookup] 1> with 1> [ 1> _Rx=void, 1> _Pmf=void (__thiscall world::* )(std::ostream &), 1> _Arg0=world, 1> _Arg1=std::ostream & 1> ] 1> while trying to match the argument list '(void (__thiscall world::* )(std::ostream &))' 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(492) : see reference to function template instantiation 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to<F>(MemberPtr,boost::detail::function::function_buffer &,boost::detail::function::member_ptr_tag)' being compiled 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> &, 1> F=void (__thiscall world::* )(std::ostream &), 1> MemberPtr=void (__thiscall world::* )(std::ostream &) 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(915) : see reference to function template instantiation 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to<Functor>(F,boost::detail::function::function_buffer &)' being compiled 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> &, 1> Functor=void (__thiscall world::* )(std::ostream &), 1> F=void (__thiscall world::* )(std::ostream &) 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(722) : see reference to function template instantiation 'void boost::function2<R,T0,T1>::assign_to<Functor>(Functor)' being compiled 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> &, 1> Functor=void (__thiscall world::* )(std::ostream &) 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(1065) : see reference to function template instantiation 'boost::function2<R,T0,T1>::function2<void(__thiscall world::* )(std::ostream &)>(Functor,int)' being compiled 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> &, 1> Functor=void (__thiscall world::* )(std::ostream &) 1> ] 1> c:\users\boris\documents\visual studio 2010\projects\test\main.cpp(14) : see reference to function template instantiation 'boost::function<Signature>::function<void(__thiscall world::* )(std::ostream &)>(Functor,int)' being compiled 1> with 1> [ 1> Signature=void (world *,std::ostream &), 1> Functor=void (__thiscall world::* )(std::ostream &) 1> ] 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2780: 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to(const boost::reference_wrapper<FunctionObj> &,boost::detail::function::function_buffer &,boost::detail::function::function_obj_ref_tag)' : expects 3 arguments - 2 provided 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(625) : see declaration of 'boost::detail::function::basic_vtable2<R,T0,T1>::assign_to' 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2780: 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to(FunctionObj,boost::detail::function::function_buffer &,boost::detail::function::function_obj_tag)' : expects 3 arguments - 2 provided 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(599) : see declaration of 'boost::detail::function::basic_vtable2<R,T0,T1>::assign_to' 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2780: 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to(MemberPtr,boost::detail::function::function_buffer &,boost::detail::function::member_ptr_tag)' : expects 3 arguments - 2 provided 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(533) : see declaration of 'boost::detail::function::basic_vtable2<R,T0,T1>::assign_to' 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1>c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(539): error C2780: 'bool boost::detail::function::basic_vtable2<R,T0,T1>::assign_to(FunctionPtr,boost::detail::function::function_buffer &,boost::detail::function::function_ptr_tag)' : expects 3 arguments - 2 provided 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] 1> c:\boost\include\boost-1_46_1\boost\function\function_template.hpp(511) : see declaration of 'boost::detail::function::basic_vtable2<R,T0,T1>::assign_to' 1> with 1> [ 1> R=void, 1> T0=world *, 1> T1=std::basic_ostream<char,std::char_traits<char>> & 1> ] ========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ========== Boris

2 1

plus<boost::gregorian::date> - how to?
by qplace 20 Mar '11

20 Mar '11

I need to be able to either add or substruct boost::gregorian::days from boost::gregorian::date. As far as I understand I have to define plus<boost::gregorian::date> and minius<boost::gregorian::date> and provide function operators for them. My question is: Function operator required in plus and minus template has a form of T operator()(const T& x, const T& y) , but I need to use not only gregorian::date, but gregorian::days as well. Any advise is greatly appreciated.

2 1

storing a boost::asio::io_service in a boost.tuple
by Sean Farrow 20 Mar '11

20 Mar '11

Hi: I need to store a boost::asio::io_service in a boost::tuple. Each boost::tuple needs an individual io_service. Given that io_service is noncopyable, and I'm working in a constructor what is the best way of doing this? Cheers Sean.

2 1

[spirit][karma][range] Range adaptors not handled by karma?
by Ravi 20 Mar '11

20 Mar '11

Hi, Does spirit karma handle boost.range adaptors correctly? The following code compiles but fails at run-time as the end of the range is not seen by karma: --8<----8<----8<----8<----8<----8<----8<----8<----8<----8<----8<----8<-- #include <boost/range/adaptors.hpp> #include <boost/assign.hpp> #include <iostream> #include <vector> #include <boost/spirit/include/karma.hpp> int main(int argc, const char* argv[]) { using namespace boost::adaptors; using namespace boost::assign; std::vector<int> input; input += 1,2,3,4,5,6,7,8,9,10; std::ostream_iterator<char> os( std::cout ); using boost::spirit::karma::int_; using boost::spirit::karma::generate_delimited; using boost::spirit::ascii::space; //generate_delimited( os, int_ % ',', space, // input | strided(2) ); // <- works generate_delimited( os, int_ % ',', space, input | copied(1,6) | strided(2) ); std::cout << std::endl; return 0; } --8<----8<----8<----8<----8<----8<----8<----8<----8<----8<----8<----8<-- The tests were done with boost 1.45. Regards, Ravi

2 2

using boost.asio with wx widgets
by Sean Farrow 20 Mar '11

20 Mar '11

Hi: I'm trying to use wx widgets with boost.asio. I'm including wx.h in the main header file-which is not being included in the header I'm concerned with now. Wx.h includes windows.h and therefore winsock.h. I'm getting the error 1189 #error : winsock.h has already been included. I've defined win32_lean_and_mean before including boost/asio.hpp. I've also tried including wx.h before asio.hpp in the header I'm dealing with now, this makes no difference I still get the same error. Has anyone got any other ideas? Any help appreciated. Regards Sean.

3 2

traversing archive file (tar, zip) directories the boost way?
by Ákos Maróy 20 Mar '11

20 Mar '11

Hi, I wonder if there is a boost-friendly API to manage directory structures in archive file formats, like tar, zip & the like? In boost iostreams, there are filters for popular compression formats, like gzip, bzip2 and zip. but these only provide stream compression / decompression - and rightfully so. In boost filesystem, one has a portable API for traversing file system directory structures, which is very nice. But I'm not aware of a boost-friendly API that would allow traversing in & managing directory structure & multiple files in archive formats, such as tar & zip. of course there are C libraries, such as libtar or zlib, or ziplib, but these are all C libraries. What I would be looking for is a way to list files & directories in an archive, extract specific files from an archive, and put files into an archive, in a nice, boost-like C++ way. Is there something like this available? Akos

1 0

About includes in numeric/ublas ....matrix.hpp and vector.hpp
by Bhushan Inamdar 20 Mar '11

20 Mar '11

Dear all, I believe, I have set the environment right for the boost libraries. I had done a program a while ago using shared pointers. And after mentioning the includes in the additional includes directories, it compiled. However, no matter what I am trying to do here, the compiler does not find matrix.hpp and vector.hpp in the attached project. I am using Boost version 1.44.0. I have checked the paths and the files do exist there. But, I do not know why my compiler keeps complaining about them being not found. The errors I am getting are as under: Error 1 fatal error C1083: Cannot open include file: 'boost/numeric/ublas/matrix.hpp': No such file or directory c:\users\user\documents\visual studio 2008\projects\dbscanalgo\dbscanalgo\clusters.h 5 DBScanAlgo Error 2 fatal error C1083: Cannot open include file: 'boost/numeric/ublas/matrix.hpp': No such file or directory c:\users\user\documents\visual studio 2008\projects\dbscanalgo\dbscanalgo\dbscan.h 5 DBScanAlgo Error 3 fatal error C1083: Cannot open include file: 'boost/numeric/ublas/matrix.hpp': No such file or directory c:\users\user\documents\visual studio 2008\projects\dbscanalgo\dbscanalgo\dbscan.h 5 DBScanAlgo Now, I have configured my paths as under: $(BOOST_ROOT) is ,....C:\Program Files\boost\boost_1_44_0 Then in VS 2008 IDE on main menu, Tools | Options | Projects and Solutions | VC++ directories... I have added... For Include Files : $(BOOST_ROOT)Boost For library files : $(BOOST_ROOT)stage\lib; $(BOOST_ROOT)\libs; $(BOOST_ROOT)bin.V2 Also, after having done this, I go to the project properties, I go to C/C++ Node and on the RHS pane in the "Additional Include Directories" option add the path to "C:\Program Files\boost\boost_1_44_0\boost\numeric\ublas". Even then, I am not able to get it working. Just for your information, I am running VS 2008 professional edition on Windows 7 OS. Please let me know if there is anything wrong here. Thanks, Bhushan

1 0

function<double(double)> - cmath
by er 19 Mar '11

19 Mar '11

Simply bringing this to the attention of the function maintainer, in case it hasn't been mentioned before, and it has any relevance (I can live with it). #include <cmath> #include <boost/function.hpp> typedef function<double(double)> f_; // error C2440 with MSVC 2010. No such problems with GCC 4.2 f_ f = log10; typedef double(*fp)(double); f_ f = fp( log10 ); // clumsy, but solves it

3 3

[context review] Review starts next Monday, Mars 21st
by Vicente BOTET 19 Mar '11

19 Mar '11

Hi all, The review of Oliver Kowalke Context library starts next Monday Mars 21st 2011, and will end on Mars 30th. Boost.Context is a basic building block library that is used for more higher abstractions. It is used by Boost.Fiber, Boost.Tasklet and Boost.Task from the same author. I really hope to see your vote and your participation in the discussions on the Boost DEVELOPMENT mailing lists! Please use [context review] as prefix of your post to make easier the review follow up. You can already download a frozen version for the review from the Vault, TinyURL: http://tinyurl.com/5r77rel or --------------------------------------------------- About the library: Boost.Context provides a possibility to switch between different user-level context and is intended to be the basis for a higher abstraction like coroutine and fiber. A user-level context represents the current execution state, including all registers and CPU flags, the instruction pointer, the stack pointer. boost::context encapsulates such a user-level context and is able to store/restore its associated user-level context. This allows multiple execution paths running on a single thread using a sort of cooperative scheduling (in contrast a thread is preemptively scheduled) - the running boost::context decides explicitly when its yields to allow another boost::context to run (user-level context switching). A context can only run on a single thread at any point in time but may be migrated between thread. A context switch between threads costs usually thousands of CPU cycles on x86 compared to a user-level context switch with few hundreds of cycles. Boost.Context differes to setjmp()/longjmp() in the fact that the C99 standard does not require that longjmp() preserves the current stack frame, e. g. jumping into a function which was exited via a call to longjmp() is undefined. Boost.Context allows to select the mechanism provided by the operating system (ucontext on UNIX, Windows Fibers on Windows) or a faster implementation provided by this library (fcontext using assembler). --------------------------------------------------- Please always state in your review, whether you think the library should be accepted as a Boost library! Additionally please consider giving feedback on the following general topics: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With what compiler? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? Regards Vicente Review Manager

1 0

[BGL] Separating twin vertices
by Shaun Jackman 19 Mar '11

19 Mar '11

Hi, I have a directed graph where every vertex has a twin vertex. It is known ahead of time which pairs of vertices are twins. I want to remove as few vertices as possible from the graph such that no vertex and its twin is in the same connected component. Could someone suggest an appropriate algorithm? I've just started delving into the BGL. So far I'm suitably impressed! Cheers, Shaun

2 5

boost::exception_detail::error_info_base does not have virtual destructor
by Jens Auer 19 Mar '11

19 Mar '11

Hi, I am compiling a project with a more strict warning set and got the following reports: Error 29 error C4265: 'boost::exception_detail::error_info_base' : class has virtual functions, but destructor is not virtual c:\work\svn\sandbox\externals\boost\include\boost-1_45\boost\exception\detail\error_info_impl.hpp 36 Error 30 error C4265: 'boost::error_info<Tag,T>' : class has virtual functions, but destructor is not virtual c:\work\svn\sandbox\externals\boost\include\boost-1_45\boost\exception\detail\error_info_impl.hpp 69 IMHO these classes should have a virtual destructor as they are intended to be used as base classes. Best wishes, Jens

8 28

[boost::thread] interrupt a future get boost::unknown_exception
by 乔志强 18 Mar '11

18 Mar '11

[Windows XP, VC++ 10, boost 1.46] When interrupt a future, the future.get() throw boost::unknown_exception, Not boost::thread_interrupted. Class boost::thread_interrupted should have a base class for current_exception_impl() to catch it ? or use BOOST_THROW_EXCEPTION in interruptible_wait) ? /////////////// namespace boost { class thread_interrupted {}; } exception_ptr current_exception_impl() { try { throw; } catch( exception_detail::clone_base & e ) { return exception_ptr(e.clone()); } ................ catch( std::exception & e ) { return exception_detail::current_exception_unknown_std_exception(e); } catch( boost::exception & e ) { return exception_detail::current_exception_unknown_boost_exception(e); } catch( ... ) { return exception_detail::current_exception_unknown_exception(); } // unknown_exception////////////////// ERROR: Throw in function (unknown) Dynamic exception type: class boost::exception_detail::clone_impl<class boost::unknown_exception> std::exception::what: Unknown exception //code ///////////////////// #include <boost/thread.hpp> #include <boost/date_time/posix_time/posix_time_types.hpp> #include <boost/thread/future.hpp> using namespace boost::posix_time; using namespace boost; int main(int argc, char** argv) { boost::packaged_task<int> pt( [=]()->int { this_thread::sleep(seconds(1000)); return 0; } ); boost::unique_future<int> fi = pt.get_future(); boost::thread task(std::move(pt)); // launch task on a thread task.interrupt(); try { int v = fi.get(); } catch (boost::exception& exc) { std::cerr << "ERROR: " << boost::diagnostic_information(exc) << std::endl; } }

4 3

[Review] Boost.Type Traits Extension by Frederic Bron
by Joel Falcou 18 Mar '11

18 Mar '11

Dear All, This is the first day of the fast track review of Frédéric Bron's extensions to the Type Traits Library.This reviews will last until March 18th, 2011 under my management. All comments and reviews are very welcome. =========== What is it? =========== This extension adds 37 new traits corresponding to the following 37 operators: - binary: ==, !=,<,<=,>,>=, , +, -, *, /, %, +=, -=, *=, /=, %=, , &&, ||, ,&, |, ^,<<,>>,&=, |=, ^=,<<=,>>= - prefix: ++, --, +, -, !, ~, * - postfix: ++, -- Each trait can detect if the operator can be used with particular types and if needed, if the return type is convertible to some type. =================== Getting the library =================== The latest version can be downloaded by different ways: - from the vault with unix line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t… - from the vault with dos line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t… - from the sandbox:http://svn.boost.org/svn/boost/sandbox/type_traits/ The entry point of the documentation is type_traits/libs/type_traits/doc/html/boost_typetraits/category/value_traits/operators.html The library has been tested with: - MSVC 8, 9, 10 on Windows, - g++ 4.4.5 on Linux, - intel 10.0 and 11.1 on Linux. To test the library, the simplest is to untar the headers in your boost include directory. For this, you can download the header part of the extension: - from the vault with unix line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t… - from the vault with dos line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t…

7 10

Specifying a NVP wrapper
by simone pilozzi 18 Mar '11

18 Mar '11

Hi All, I am working with the serialization library and I made an example class like this. class Contact{ public: Contact(){} Contact(string& name, int phonenumber,long contactdate):name_(name), pnumber_(phonenumber),contactdate_(contactdate){} const string getName() const{return name_;} const long getPhone() const{return pnumber_;} const long getDate() const{return contactdate_;} private: string name_; long pnumber_,contactdate_; friend class boost::serialization::access; template<typename Archive> void serialize(Archive& ar, const unsigned int version){ ar & boost::serialization::make_nvp("name", name_); ar & boost::serialization::make_nvp("phone", pnumber_); ar & boost::serialization::make_nvp("contactdate", contactdate_); } }; Now I would like to allocate the xml file created with the use of this class in a vector, and this is the function: void getFromFile(std::vector<Contact>& contacts,const char* file){ std::ifstream ifile(file); boost::archive::xml_iarchive ia(ifile); ia >> contacts; ifile.close(); } The compiler complains because it misses a NVP wrapper for the class. I could not find an example for that in boost. Could you help me ? Thanks in advance Simone

3 2

Invitation à se connecter sur LinkedIn
by Germain Barret via LinkedIn 18 Mar '11

18 Mar '11

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1 0

[regexp] Replace a substring with a regexp
by Olivier Tournaire 18 Mar '11

18 Mar '11

Hi all, I am not really familiar with regexp, an I am facing a problem. I have some strings containing unicode sequences (like "\u****"), and I would like to replace them with html sequences (such that "\u****" becomes "&#x****;"). I think I can do that with boost regexp, but I really do not know how. The major problem is that I do not now in advance what are the characters for "****". I however know that they are always 4 and alphanumeric. So, I have to detect them and also append after a ";". Do you have any hint on how to do that? Best regards, Olivier

3 5

Boost conflict with OpenCV, Eigen?
by Prva Ponta 18 Mar '11

18 Mar '11

Hi there, I have a program that uses Filesystem, which compiles and runs without problem, but only if used by itself. If I use Filesystem within a program that also needs OpenCV and Eigen libraries, there seems to be a conflict: ... In file included from C:\boost_1_45_0/boost/filesystem/v3/path_traits.hpp:22:0, from C:\boost_1_45_0/boost/filesystem/v3/path.hpp:25, from C:\boost_1_45_0/boost/filesystem.hpp:32, from ..\src\ComputeNatScaleFunction.cpp:18: C:\boost_1_45_0/boost/type_traits/decay.hpp: In instantiation of 'boost::decay<cv::<anonymous enum> >': C:\cmake_binaries\include/opencv2/core/operations.hpp:766:23: instantiated from here C:\boost_1_45_0/boost/type_traits/decay.hpp:28:66: error: 'cv::' is/uses anonymous type C:\boost_1_45_0/boost/type_traits/decay.hpp:28:66: error: trying to instantiate 'template struct boost::remove_reference' C:\boost_1_45_0/boost/type_traits/decay.hpp:38:17: error: 'cv::' is/uses anonymous type C:\boost_1_45_0/boost/type_traits/decay.hpp:38:17: error: trying to instantiate 'template struct boost::remove_reference' C:\boost_1_45_0/boost/type_traits/decay.hpp: In instantiation of 'boost::decay<cv::<anonymous enum> >': C:\cmake_binaries\include/opencv2/core/operations.hpp:917:21: instantiated from here C:\boost_1_45_0/boost/type_traits/decay.hpp:28:66: error: 'cv::' is/uses anonymous type C:\boost_1_45_0/boost/type_traits/decay.hpp:28:66: error: trying to instantiate 'template struct boost::remove_reference' C:\boost_1_45_0/boost/type_traits/decay.hpp:38:17: error: 'cv::' is/uses anonymous type C:\boost_1_45_0/boost/type_traits/decay.hpp:38:17: error: trying to instantiate 'template struct boost::remove_reference' C:\boost_1_45_0/boost/type_traits/decay.hpp: In instantiation of 'boost::decay<Eigen::<anonymous enum> >': C:\Eigen2/Eigen/src/Core/GenericPacketMath.h:116:18: instantiated from here C:\boost_1_45_0/boost/type_traits/decay.hpp:28:66: error: 'Eigen::' is/uses anonymous type C:\boost_1_45_0/boost/type_traits/decay.hpp:28:66: error: trying to instantiate 'template struct boost::remove_reference' C:\boost_1_45_0/boost/type_traits/decay.hpp:38:17: error: 'Eigen::' is/uses anonymous type C:\boost_1_45_0/boost/type_traits/decay.hpp:38:17: error: trying to instantiate 'template struct boost::remove_reference' etc. Are there known conflicts between Boost (1.45) and OpenCV 2.2/Eigen2/other libraries? I am using Eclipse CDT and MinGW toolchain. After going through problems described in http://boost.2283326.n4.nabble.com/How-to-built-boost-td3053130.html, my Filesystem library is of version 3, whereas other ones are of version 2. Cheers, PP

1 0

[Graph] Switching from depth_first_search to depth_first_visit
by Marcus Riemer 17 Mar '11

17 Mar '11

Hello there! I just stumbled over a little bug that is simply due to the wrong visiting pattern used. From what I understand it should simply print a graph with children being indented. The visitor defined for the task itself is just fine. Problem is that currently a depth first *search* is used, which prints each vertex only once. So from my understanding the only thing I need to do is to replace that search with a visit. Sadly replacing the call to depth_first_visit with a call to depth_first_visit is not as easy as I thought ... For the record: The search call itself looks like this: boost::depth_first_search(mGraph, boost::visitor(printer).root_vertex(start)); Looking at the documentation [0] it seems that there is no version with named parameters for the depth first visit. So I need to pass the graph itself, the starting vertex, the visitor and a color map. And its the color map that troubles me ... I have tried around a little to construct such a thing, but so far without success. My try can be found at [1]. This results in a massive compilation error [2]. I am not really experienced with the extent templates are used in the BGL and have no idea what the compiler tries to tell me. Could anyone give me a hint what I am doing wrong? If more sourcecode is required thats not a problem at all. Simply tell me if anything is missing. Access to the source is also not a problem, compilation is quite easy using cmake. Thanks in advance Marcus Riemer [0] http://www.boost.org/doc/libs/1_44_0/libs/graph/doc/depth_first_visit.html [1] http://pastebin.com/ALvnTdj9 [2] http://pastebin.com/bh6d4NpH

2 3

[BGL] clear_out_edges and MutableIncidenceGraph
by Shaun Jackman 17 Mar '11

17 Mar '11

Hi, adjacency_list implements clear_out_edges, but it's not required by any of the graph concepts: http://www.boost.org/doc/libs/1_46_1/libs/graph/doc/graph_concepts.html Could it be added to MutableIncidenceGraph? Actually, now that I check, I don't see MutableIncidenceGraph on that page either, although it is in graph_concepts.hpp. MutableIncidenceGraph requires remove_edge and remove_out_edge_if. clear_out_edges would fit nicely in here, and clear_in_edges in MutableBidirectionalGraph. Cheers, Shaun

1 0

shared_lock( ) causes Segmentation Fault in CentOS 5.5 x64?
by DesertFish 17 Mar '11

17 Mar '11

Dear Pals, I wrote a server program, and there is a class called "apInfoMutex", which can store client's file descriptor info and what messages they sent; the class code is as below: --- class apInfoTable{ public: apInfoTable(); boost::shared_mutex rwMutex; void addFD(int apfd, char *srvceType, vector<string> *codeList); void delFD(int apfd); bool getFD(list<int> *des, char *srvceType, char *srvceCode); private: boost::unordered_map<int, boost::unordered_set<pair<string, string> > > tableFD; boost::unordered_map<pair<string, string>, boost::unordered_set<int> > tablePush; }; --- there is just one apInfoTable as global declaration in my program, but there would be two or more threads to calling these public method at the same time, and there is a method called "getFD()" in this class, the code is as below: --- bool apInfoTable::getFD(list<int> *des, char *type, char *code){ bool flag=false; boost::shared_lock<boost::shared_mutex> lock(rwMutex); for(boost::unordered_set<int>::iterator it=tablePush[pair<string, string> (type, code)].begin();it!=tablePush[pair<string, string>(type, code)].end ();it++){ flag=true; des->push_back(*it); } return flag; } --- I found if I calling getFD() method like this: char type[12]; char code[32]; list<int> fdList; memset(type, 0x00, sizeof(type)); memset(code, 0x00, sizeof(code)); memcpy(type, "My Type", sizeof("My Type")); memcpy(code, "My Code", sizeof("My Code")); fdList.clear(); bool rc=getFD(&fdList, type, code); I will got "Segmentation Fault" problem, but if I put different parameter like this: bool rc=getFD(&fdList, "My Type", "My Code"); or using boost::mutex instead of shared_lock() and shared_mutex in getFD(), there wouldn't be any problem when running program. is there any problem with my code? or did I use shared_lock() and shared_mutex incorrectly? P.S--I tried using unique_lock or scoped_lock instead of shared_lock(), but there is just no any problem when I using normal boost::mutex sincerely thanks to you Zap

5 6

[Review] Type Traits Extension ending tomorrow
by Joel Falcou 17 Mar '11

17 Mar '11

Dear All, The fast track review of Frédéric Bron's extensions to the Type Traits Library is ending tomorrow. If you plan to submit a review, please do so as soon as possible. Thanks in advance to all participants of the review. =========== What is it? =========== This extension adds 37 new traits corresponding to the following 37 operators: - binary: ==, !=,<,<=,>,>=, , +, -, *, /, %, +=, -=, *=, /=, %=, , &&, ||, ,&, |, ^,<<,>>,&=, |=, ^=,<<=,>>= - prefix: ++, --, +, -, !, ~, * - postfix: ++, -- Each trait can detect if the operator can be used with particular types and if needed, if the return type is convertible to some type. =================== Getting the library =================== The latest version can be downloaded by different ways: - from the vault with unix line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t… - from the vault with dos line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t… - from the sandbox:http://svn.boost.org/svn/boost/sandbox/type_traits/ The entry point of the documentation is type_traits/libs/type_traits/doc/html/boost_typetraits/category/value_traits/operators.html The library has been tested with: - MSVC 8, 9, 10 on Windows, - g++ 4.4.5 on Linux, - intel 10.0 and 11.1 on Linux. To test the library, the simplest is to untar the headers in your boost include directory. For this, you can download the header part of the extension: - from the vault with unix line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t… - from the vault with dos line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t…

3 2

Boost profile for ODB
by Boris Kolpackov 17 Mar '11

17 Mar '11

Hi, I would like to briefly mention that we have released the Boost profile for ODB, an open-source object-relational mapping (ORM) system for C++. The Boost profile provides glue code that seamlessly integrates various Boost components, such as smart pointers, containers, and value types, with ODB. This initial release of the profile covers the most commonly used types from the smart_ptr, unordered, and date_time Boost libraries. For example, now we can easily persist a class like this: #pragma db object class employee { ... boost::gregorian::date born_; boost::unordered_set<std::string> emails_; boost::shared_ptr<employer> employer_; }; For a more detailed discussion of the Boost profile, see the following blog post: http://www.codesynthesis.com/~boris/blog/2011/03/16/odb-1-2-0-released/ Or refer directly to Part III, "Profiles" in the ODB Manual: http://www.codesynthesis.com/products/odb/doc/manual.xhtml#III Boris

1 0

[units] Creating specific unit quantities
by Ryan 17 Mar '11

17 Mar '11

In the Boost Unit documentation there are examples on creating quantities using a dimension. There doesn't seem to be any documentation on using a specific type of dimension as a quantity. Is it possible to create a quantity with a specific type of dimension value? using namespace boost::units; using namespace boost::units::si; quantity<length> L = 2.0*meters; //Is it possible to have meters instead of length as a quantity? quantity<???> L = 2.0 * meters; Ryan

2 14

Library Developers Battling Cyclic Header Dependency
by Ryan 17 Mar '11

17 Mar '11

In the boost library system certain libraries need to be compiled and linked into a project. For example, libraries would need to be compiled to remove cyclic header dependencies. In the boost library system I coundn't find any .cpp files that would indecate a compilable library. So how do library developers create compilable files in the boost libraries? The following two files would need to be broken up and compiled to remove the dependencies, correct? Ryan //File A.hpp class B; class A { double x; public: B convertToB(void) { return B(x); } }; //File B.hpp class A; class B { double y; public: A convertToA(void) { return A(y); } };

6 13

[Serialization] Segfault while serializing derived pointers using multi DLLs
by François Mauger 17 Mar '11

17 Mar '11

Hi all (and particularly Boost/(De-)Serializer), I use Boost 1.44, gcc 4.4.1, Linux. The problem: I have two home made libraries compiled as DLL under linux: - 'datatools' provides the 'libdatatools.so' DLL - 'brio' provides the 'libbrio.so' DLL I use Boost serialization features for derived pointers. Below are the details: STEP 1: 'datatools' is the base library. It defines: - its own namespace: 'datatools' - a virtual class (interface) named 'i_serializable' from which all other serializable classes should inherit in order to benefit of the (de)serialization mechanism through pointer to this base class. [see http://www.boost.org/doc/libs/1_46_1/libs/serialization/doc/serialization.h…] - some concrete classes (A, B, C) that inherit from the 'i_serializable' interface and register themselves using the export key features described in http://www.boost.org/doc/libs/1_46_1/libs/serialization/doc/special.html#ex… Typical inheritance diagram looks like: <pre> datatools::i_serializable | +--------------+--------------+ | | | datatools::A datatools::B datatools::C | datatools::A' </pre> Here is the typical model of the 'A.hpp' header file for the A class: <pre> ... #include <datatools/serialization/archives_list.hpp> // include Boost/Serialization text/XML/binary archives #include <datatools/serialization/i_serializable.hpp> // include the abstract mother interface class ... namespace datatools { class A: public i_serializable { blah-blah.. // no inline code (from http://www.boost.org/doc/libs/1_46_1/libs/serialization/doc/special.html#dl…) template<class Archive> void serialize (Archive & ar, const unsigned int version); }; } // register the class with a specific GUID: BOOST_CLASS_EXPORT_KEY2 (datatools::A, "datatools::A"); </pre> Here is the model of the 'A.cpp' implementation file: <pre> namespace datatools { ... template<class Archive> void A::serialize (Archive & ar, const unsigned int version) { ar & boost::serialization::make_nvp( "datatools__serialization__i_serializable", boost::serialization::base_object<datatools::serialization::i_serializable >(*this) ); ar & more data (with NVP stuff)...; } } // end of namespace datatools BOOST_CLASS_EXPORT_IMPLEMENT(datatools::A) // explicit instantiation for all kind of known archives: #include <datatools/serialization/archives_list.hpp> // include the known text/XML/binary archives template void datatools::A::serialize(boost::archive::text_oarchive & ar, const unsigned int version); template void datatools::A::serialize(boost::archive::text_iarchive & ar, const unsigned int version); template void datatools::A::serialize(boost::archive::xml_oarchive & ar, const unsigned int version); ... more... </pre> Finaly, I can compile all this stuff using gcc and build the 'libdatatools.so' library which I prepend to my LD_LIBRARY_PATH. Everything looks fine. A test program 'prg1.cpp' that links against only 'libdatatools.so' and 'libboost_serialization.so' works prefectly, serialiazing and deserialiazing any collection of pointers to A,B, or C classes without problem. A must ! Thanks to Robert for that magic ! At this point, everything looks (is?) fine. Note that I have followed (in principle) all the guidelines provided by Robert. STEP 2: Now let's consider the actual problem ! As said before, my 'datatools' library is the base of some modular project with some other libraries that depend on 'datatools' (and Boost/Serialization). The 'brio' library is such a beast: <pre> Boost/Serialization | datatools | brio </pre> It has its own namespace: 'brio' It provides a few other dedicated classes, inherited from the 'datatools::i_serializable' abstract class and which are serializable via Boost. Let's consider the serializable 'brio::D' class, designed on the model of 'datatools::A' and using the same implementation recommendations. I have followed the guidelines use for the 'datatools::A' class to write both 'D.hpp' and 'D.cpp' files. Now the inheritance scheme is: <pre> datatools::i_serializable : | : +--------------+--------------+------------+-----+- - - - | | | : | datatools::A datatools::B datatools::C : brio::D | : datatools::A' : libdatatools.so scope : libbrio.so scope : </pre> I can compile the 'libbrio.so' DLL without any problem. Now I want to run a sample program 'prg2.cpp' that performs some (de)serialization operations on a collection of pointers to 'datatools::A', 'datatools::B', 'datatools::C' AND 'brio::D' instances. This program is linked against the following libraries (among others): - libbrio.so - libdatatools.so - libboost_serialization.so Well, it compiles perfectly. Note this program links against third-party libraries too, among them some are explicitely using 'dlopen' and 'dlclose' to satisfy internal and critical features that are out of my scope. I have no idea if this can have side-effect. However, when I run it, I observed the following behaviour: - all (de)serialization operations are done properly and I get files with embeded (text/XML...) portable archives than can be reloaded without problem. - at the END of the program, while some cleaning code is invoked (some kind of deep buried code out of my skills and understanding), I get a Segmentation fault. Here is a dump of the GDB backtrace: <pre> Program received signal SIGSEGV, Segmentation fault. 0x02647c78 in boost::serialization::typeid_system::extended_type_info_typeid_0::is_less_than(boost::serialization::extended_type_info const&) const () from /scratch/sw/boost/install-1_44_0-Linux-i686-gcc44/lib/libboost_serialization.so.1.44.0 (gdb) bt #0 0x02647c78 in boost::serialization::typeid_system::extended_type_info_typeid_0::is_less_than(boost::serialization::extended_type_info const&) const () from /scratch/sw/boost/install-1_44_0-Linux-i686-gcc44/lib/libboost_serialization.so.1.44.0 #1 0x0264737b in boost::serialization::extended_type_info::operator<(boost::serialization::extended_type_info const&) const () from /scratch/sw/boost/install-1_44_0-Linux-i686-gcc44/lib/libboost_serialization.so.1.44.0 #2 0x0264dcac in boost::serialization::void_cast_detail::void_caster::operator<(boost::serialization::void_cast_detail::void_caster const&) const () from /scratch/sw/boost/install-1_44_0-Linux-i686-gcc44/lib/libboost_serialization.so.1.44.0 #3 0x0264e56d in boost::serialization::void_cast_detail::void_caster::recursive_unregister() const () from /scratch/sw/boost/install-1_44_0-Linux-i686-gcc44/lib/libboost_serialization.so.1.44.0 #4 0x0264ed8d in boost::serialization::void_cast_detail::void_caster_shortcut::~void_caster_shortcut() () from /scratch/sw/boost/install-1_44_0-Linux-i686-gcc44/lib/libboost_serialization.so.1.44.0 #5 0x0264e5ee in boost::serialization::void_cast_detail::void_caster::recursive_unregister() const () from /scratch/sw/boost/install-1_44_0-Linux-i686-gcc44/lib/libboost_serialization.so.1.44.0 #6 0x024a6da7 in boost::serialization::void_cast_detail::void_caster_primitive<datatools::test::more_data_t, datatools::test::data_t>::~void_caster_primitive() () from /home/mauger/Private/Work/lpc_nemo_svn/sw/datatools/datatools_trunk/Linux-i686/lib/libdatatools.so #7 0x024a6f04 in boost::serialization::detail::singleton_wrapper<boost::serialization::void_cast_detail::void_caster_primitive<datatools::test::more_data_t, datatools::test::data_t> >::~singleton_wrapper() () from /home/mauger/Private/Work/lpc_nemo_svn/sw/datatools/datatools_trunk/Linux-i686/lib/libdatatools.so #8 0x0298c428 in __cxa_finalize (d=0x2609830) at cxa_finalize.c:56 #9 0x02426f04 in __do_global_dtors_aux () from /home/mauger/Private/Work/lpc_nemo_svn/sw/datatools/datatools_trunk/Linux-i686/lib/libdatatools.so #10 0x02534100 in _fini () from /home/mauger/Private/Work/lpc_nemo_svn/sw/datatools/datatools_trunk/Linux-i686/lib/libdatatools.so #11 0x0011dee6 in _dl_fini () at dl-fini.c:248 #12 0x0298c05f in __run_exit_handlers (status=0, listp=0x2a9e304, run_list_atexit=true) at exit.c:78 #13 0x0298c0cf in *__GI_exit (status=0) at exit.c:100 #14 0x02973b5e in __libc_start_main (main=0x8059495 <main>, argc=1, ubp_av=0xbfffcfd4, init=0x8061c40 <__libc_csu_init>, fini=0x8061c30 <__libc_csu_fini>, rtld_fini=0x11dcc0 <_dl_fini>, stack_end=0xbfffcfcc) at libc-start.c:252 #15 0x080592c1 in _start () at ../sysdeps/i386/elf/start.S:119 </pre> If one ignores the nasty details from this stack (local pathes and names), one observe that the problem seems to be related to some unregistration of some Boost/Serialization material. It occurs while the executable is trying to destruct some singleton_wrapper template class that manages some serializable classes from the 'datatools' library: - class 'datatools::test::more_data_t' (call it A') - and its mother class 'datatools::test::data_t', (call it A) inherited from 'datatools::i_serializable'. I expect such singleton is a static instance attached in some DLL. Am I wrong ? If not, which DLL is concerned 'libdatatools.so', 'libbrio.so' ? My feeling is that I have a problem with some arbitrary order of library unloading and messy unregistration that comes with. Unless there is a specific order to aggregate module within in DLL (A.o B.o A'.o...). Unfortunately, my skills are too limited to make a better idea and find a solution. There is some comments by Robert concerning such possible problems, but I'm not sure it makes sense in my case. So I will really appreciate if someone could advise me and possibly give me some hints. Thanks a lot for attention and help. Apologize for this rather long and technical issue. Regards frc -- François Mauger Groupe "Interactions Fondamentales et Nature du Neutrino" NEMO-3/SuperNEMO Collaboration LPC Caen-CNRS/IN2P3-UCBN-ENSICAEN Département de Physique -- Université de Caen Basse-Normandie Adresse/address: Laboratoire de Physique Corpusculaire de Caen (UMR 6534) ENSICAEN 6, Boulevard du Marechal Juin 14050 CAEN Cedex FRANCE Courriel/e-mail: mauger(a)lpccaen.in2p3.fr Tél./phone: 02 31 45 25 12 / (+33) 2 31 45 25 12 Fax: 02 31 45 25 49 / (+33) 2 31 45 25 49

1 0

[lexical_cast] crash using Intel 12.0 with optimizations enabled
by Thomas Mang 17 Mar '11

17 Mar '11

Hi, I tracked down a crash to a call to boost::lexical_cast (Boost 1.46.1( when using the Intel 12.0 compiler for Windows (embedded into MSVC8) if optimizations are enabled. I would have expected the mini-program below to work smoothly, but instead the second catch-handler is entered (unknown exception). The offending compiler option is /O; in all cases except of /Od [all optimizations disabled] the exception is raised. May I strongly suppose this is either a boost or an Intel compiler issue, or did I misunderstand something ? Below are full command-line compiler options and teh program. Thanks and best, Thomas command line options: /c /O2 /Og /Qipo /I "C:\Libraries\Boost\boost_1_46_1" /D "WIN32" /D "NDEBUG" /D "_CONSOLE" /D "_UNICODE" /D "UNICODE" /EHsc /MD /GS- /fp:strict /Za /Fo"ReleaseFinal/" /W3 /nologo /Wp64 /Zi /Qfp-speculation:strict /Quse-intel-optimized-headers /Qintel-extensions- mini-program: #include <iostream> #include <ostream> #include <string> #include "boost/lexical_cast.hpp" int main() { try { std::string X = boost::lexical_cast<std::string>(2 - 1); std::cout << X << std::endl; } catch (boost::bad_lexical_cast const &) { std::cout << "boost::lexical_cast exception occurred."; } catch (...) { std::cout << "An unknown exception occurred."; } }

3 3

Compiling Boost with 4 byte packing...
by Brian Nantz 17 Mar '11

17 Mar '11

I am trying to get boost asio to work with my code (which is using 4 byte struct member alignment and _cdecl calling convention). I get the following error when calling asio::async_write: Run-Time Check Failure #0 - The value of ESP was not properly saved across a function call. This is usually a result of calling a function declared with one calling convention with a function pointer declared with a different calling convention. What am I missing? I have read everything on ABI that I can find: http://www.boost.org/development/separate_compilation.html I changed boost\config\abi\msvc_prefix.hpp to use #pragma pack(push,4). I also am using the command line option for bjam: cxxflags="/Zp4 /Gd" The Microsoft documentation seems to indicate that the /Zp should override the #pragma if the #pragma is larger or equal: http://msdn.microsoft.com/en-us/library/ms253935.aspx http://msdn.microsoft.com/en-us/library/46t77ak2.aspx Any help would be greatly appreciated, Brian

2 1

[boost-user][asio]How can i limit tcpserver's connection count?
by rhapsodyn 16 Mar '11

16 Mar '11

here‘s the code server： class tcp_server { public: tcp_server(boost::asio::io_service& io_service) : acceptor_(io_service),limit(0) { tcp::endpoint endpoint(tcp::v4(), 10000); acceptor_.open(endpoint.protocol()); acceptor_.bind(endpoint); acceptor_.listen(1); start_accept(); } private: void start_accept() { while(1) { if(limit < 1) break; } tcp::socket* socket = new tcp::socket(acceptor_.io_service()); acceptor_.async_accept(*socket, boost::bind( &tcp_server::handle_accept, this, socket, boost::asio::placeholders::error)); } void handle_accept(tcp::socket* s, const boost::system::error_code& error) { if (!error) { ++limit; start_accept(); } } tcp::acceptor acceptor_; int limit; }; client： int main(int argc, char* argv[]) { int i = 0; try { boost::asio::io_service io_service; tcp::resolver resolver(io_service); tcp::resolver::query query("127.0.0.1", "10000"); tcp::resolver::iterator endpoint_iterator = resolver.resolve(query); tcp::endpoint endpoint = *endpoint_iterator; tcp::socket socket(io_service); socket.connect(endpoint); while(1) {} } catch (std::exception& e) { std::cerr << e.what() << std::endl; } return 0; } I thought i can only launch 1 client, but fact is: i can start two clients and the 3rd one just cerr the what(), what happend there? Is there some better way to get & limit the "living-connection" of the server? -- View this message in context: http://boost.2283326.n4.nabble.com/boost-user-asio-How-can-i-limit-tcpserve… Sent from the Boost - Users mailing list archive at Nabble.com.

4 5

boost::asio::write(), big data-chunks, socket-error 10053
by Sebastian Rudek 15 Mar '11

15 Mar '11

Hello I am having trouble with Sockets under Windows and Linux. When attempting to send much data through boost::asio::write(), the socket error 10053 - connection aborted - occurs. I am sending from a Windows machine over the local network to a server (not using boost), running on linux. This server uses a select to determine whether there is something to read or not. Sending not lots of data, for example 500 bytes, does not fail. But sending some hundred of kilobytes or even megabytes, fails. Does a timeout occur? why? and how can i make my client to transfer all of its data? did you experience something similar? Thanks in advance, regards Sebastian -- Sebastian Rudek, Softwareentwickler Lyncker& Theis GmbH Wilhelmstr. 16 65185 Wiesbaden Germany Fon +49 611/9006951 Fax +49 611/9406125 Handelsregister: HRB 23156 Amtsgericht Wiesbaden Steuernummer: 4323897052 USt-IdNr.: DE255806399 Geschäftsführer: Filip Lyncker, Armin Theis, Patrick Schmidt

1 0

boost::bind can't bind bind_t type right?
by ???? 15 Mar '11

15 Mar '11

#include <iostream> #include <boost/bind.hpp> #include <boost/function.hpp> class test1 { public: template<typename S> double handle(S s) { s(1); std::cout<<"test1\n"; return 1; } template<typename F> void handle1(F f){ boost::bind(&test1::handle<F>,this,f)(); } }; class test2 { public: double handle(int i) { std::cout<<"test2\n"; return i; } }; int _tmain(int argc, _TCHAR* argv[]) { test2 t2; test1 t1; t1.handle1(boost::bind(&test2::handle,t2,_1)); return 0; } in test1::handle1 complie fail on vs2010 and gcc 4.4.1 vs 2010 error:error C2664: "R boost::_mfi::mf1<R,T,A1>::operator ()<test1>(const U &,A1) const": can't convert "double"to "boost::_bi::bind_t<R,F,L>" . but boost::bind(&test1::handle<F>,this,f)(); f is not double,f is bind_t and double only return_type. by the way,boost::bind(&test1::handle<F>,this,boost::ref(f))(); can work.

2 1

[Regex] Search Substring with paranthesis
by Subhash Nagre 15 Mar '11

15 Mar '11

Hello, I have a string "(123) Hello" and I want to seach String (123) using boost::regex, Also I needed to do a full word search, so I added \b in the end. Here is my code std::string searchWord = "(123)"; searchWord += "\\" + "b"; // Step 1 boost::regex expression; expression.assign(searchWord); std::string completeStr = "(123) Hello (123)"; std::string::const_iterator start = completeStr.begin(); std::string::const_iterator end = completeStr.end(); boost::smatch what; while (boost::regex_search(start, end, what, expression)) { int32 foundPos = what.position(); int32 foundLen = what.length(); std::string foundString(start + foundPos, start + foundPos + foundLen); //This foundStr is 123, beacuse it finds a metacharacter in the seach expression // Perform some task with foundString start += foundPos + foundLen; } How Can I get (123) back and foundPos and foundLen as 0 and 5 respetively. I tried creating my search expression as /(123/), but it didn't worked. Also if I don't add \b in the search expression in Step 1, even in that case the foundStr is 123 but in that case, the match will be true even for (1234), which I don't want. I want to find full words only. Is there is any flag in boost::regex which can help me out or how can I perform my task. Thanks in advance Subhash

3 2

[1.46.1] Boost 1.46.1 Release available
by Beman Dawes 15 Mar '11

15 Mar '11

Release 1.46.1 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This is a bug fix release that is otherwise the same as 1.46.0. For details, including download links, see http://www.boost.org/users/news/version_1_46_1 The release can also be downloaded directly from SourceForge. See http://sourceforge.net/projects/boost/files/ To install this release on your system, see http://www.boost.org/doc/libs/release/more/getting_started/index.html Thanks, --The Boost release team Beman Dawes Daniel James Eric Niebler Rene Rivera Vladimir Prus

2 1

[StateChart] pass objectpointer to FSM?
by Bernt-Johan Bergshaven 15 Mar '11

15 Mar '11

Hello, first; thank you for an excellent library collection. I recently discovered it, and I'm impressed! My question: How can I pass a pointer to an object into the state machine? I want to use my state machine to control a real-life elevator. All the functions for controlling this elevator is inside class Elevator; I.e: myElevator->startEngine(UP); I've tried different approaches as you might see in my attached code, but I keep getting this error: statemachine: ../boost/boost/cast.hpp:97: Target boost::polymorphic_downcast(Source*) [with Target = ElevatorSM*, Source = boost::statechart::state_machine<ElevatorSM, ElevatorActive>]: Assertion `dynamic_cast<Target>(x) == x' failed. Aborted h-file: http://codepad.org/i3rAjT1p cpp-file: http://codepad.org/TpaWluCz Appreciate your help, Bernt-Johan Bergshaven, Norway

2 5

how to create a tuple from an mpl sequence?
by Peter Foelsche 15 Mar '11

15 Mar '11

I've got some mpl sequence from which I want to create a tuple. Anybody any clue? I also looked into fusion (why is there so much overlap to mpl?) but did not find anything. Tried fusion::result_of::push_back without much success. Tried fusion::vector with fusion::result_of::push_back . Does this functionality exist? Peter

2 1

[uBLAS] Identity Matrix Constructor vs Resize
by Ryan 14 Mar '11

14 Mar '11

I have an identity matrix that when initialized with the constructor I don't get an error. If I do a default construction and then resize the matrix I get a runtime error. I'm not sure the difference. Could someone enlighten me? Ryan using namespace boost::numeric::ublas; template<typename matrixT> matrix_range<matrixT> topleft (matrixT & M) { return subrange(M, 0, 3, 0, 3); } int main(int, char const* []) { vector<double> initial(3); initial[0] = 10; initial[0] = 100; initial[0] = 2; //I realize that "matrix<double> P(zero_matrix<double>(9,9));" would do the same thing as below. //This is extracted from a class and the constructor needs to to this. matrix<double> P; //This is a class variable P.resize(9,9); //This happens in the constructor P.clear(); //This happens in the constructor //The following runs without errors //identity_matrix<double> identity(3); //This causes a run time error. identity_matrix<double> identity; identity.resize(3); topleft(P) = initial[0] * identity; return 0; }

1 0

backporting filesystem v3
by Arash Abghari 14 Mar '11

14 Mar '11

Hi, I wonder if it is possible to backport filesystem v3 to 1.40 by replacing source folder from 1.46. Thanks Arash

2 2

boost::mutex over a socket
by Marco Piacentini 14 Mar '11

14 Mar '11

Hi guys...I've 2 thread and I would like that one of these performs a synchronous read, menawhile the other performs a synchrounous write...adn obviously they share the same socket.....the signature of the functions are the following: length=boost::asio::read(socket_,boost::asio::buffer(msg,sizeof(msg)), ec); boost::asio::write(socket_,boost::asio::buffer(msgToSend,sizeof(msgToSend))); socket_ is a private field of the classe Server. How can I use the mutex to perform concurrently and safetly these operations? Thanks..

2 4

[GIL] Compilation times
by Germán Diago 14 Mar '11

14 Mar '11

Hello. I'm using g++-4.4 with boost libraries and they're great. However, I have to use some image manipulation algorithms for two types of images (rgb8 and gray). I'm using it successfully, however, compilation times have increased a lot: I use apply_operation and any_image and any_image_view with two types each (rgb8 and gray8) Is there a way to decrease compile times? Thanks in advance.

2 2

Small logic::tribool riddle
by Thomas Jarosch 14 Mar '11

14 Mar '11

Hello, here's a small boost::logic::tribool riddle: -<snip>------------------------------------- #include <iostream> #include <boost/logic/tribool.hpp> int main(void) { boost::logic::tribool foo(boost::logic::indeterminate); if (foo != true) { std::cout << "reached1\n"; } if (foo == boost::logic::indeterminate) { std::cout << "reached2\n"; } return 0; } -<snap>------------------------------------- Try to determine the printed result without looking at the boost::logic::tribool implementation / documentation. Intuitive? A coworker just shot himself in the foot... Best regards, Thomas Jarosch

4 6

Re: [Boost-users] Boost-users Digest, Vol 2660, Issue 1
by Leon Sit 14 Mar '11

14 Mar '11

> > ---------- Forwarded message ---------- > From: Joel Falcou <joel.falcou(a)lri.fr> > To: boost-users(a)lists.boost.org > Date: Sat, 12 Mar 2011 08:24:53 +0100 > Subject: Re: [Boost-users] [proto] Object got sliced when passed by > reference > I just compiled your smaple using g++-4.5 and i got: > > logical_and( > logical_or( > terminal(4baseI2F1E) > , terminal(4baseI2F2E) > ) > , terminal(4baseI2F3E) > ) > hodqhoqw > 0 > > Why is I think the correct answer. So this is tied to some MSVC specific > behavior, i guess mayeb on how the terminal< base<_> const &> is matched. > matching terminal< base<_> > should be enough I think no ? Could you try ? > > HTH > > > > Thats what I did at the very beginning but fail. So I moved on to try const& but still fail. Before I started using proto, I hand-craft some overloaded operator to return the expression object too but failed with the same error. This makes me think that it is a compiler bug too. Should I try something else too?

1 0

[hash] Performance & distribution, variable bit width
by Sebastian Karlsson 14 Mar '11

14 Mar '11

As I use boost::hash quite a bit I have a few questions which the documentation seems to leave out. First of all it would be terrific if there was a performance & distribution benchmark as a part of the documentation to make it easier to evaluate the merits of using it. Secondly I'm a bit stumped on why the return value is fixed to size_t for a couple of reasons. Bit width of size_t isn't guaranteed to be constant, wouldn't this severely affect the distribution properties of the hashing algorithm used? Furthermore it would be great if the user could choose the bit width of the hash. Often the birthday problem is relevant, and being able to swap to using a 64 bit hash easily is something that doesn't seem possible but often desirable. Kind regards, Sebastian Karlsson

1 0

punits][accumulators] buggy behavior for min accumulator of quantities
by alfC 14 Mar '11

14 Mar '11

Hi, Sometimes it is difficult to make boost::units quantities with other libraries. For example to have boost::accumulators mean work with units, one has to specialize division by integer for quantities. In this example the accumulators and units compiles out of the box but gives an incorrect answer. #include<boost/accumulators/accumulators.hpp> #include <boost/accumulators/statistics/min.hpp> // or other stat features #include <boost/accumulators/statistics/max.hpp> // or other stat features #include<boost/units/systems/si.hpp> #include<boost/units/io.hpp> using namespace boost::accumulators; using namespace boost::units; int main(){ accumulator_set<quantity<si::time>, features<tag::min, tag::max> > a; a(2.1*si::second); a(2.0*si::second); a(4.1*si::second); std::cout << extract::min(a)<< " " << extract::max(a)<< std::endl ; return 0; } It prints: 0 s 4.1 s instead of: 2.1 s 4.1 s So, it seems that the min extractor fails for quantities. I would like to know if there is a way to correctly specialize "min" for quantities. (By the way, std::min for quantities works fine). However the behavior is unfortunate in the first place. Regardless of the solution I would label this as a bug of one of the two libraries. Thank you, Alfredo

2 3

Preventing iostreams from accessing freed memory
by Adam Nielsen 14 Mar '11

14 Mar '11

Hi all, I'm unable to prevent Boost iostreams from accessing memory once it has been freed, and I'm hoping someone here familiar with iostreams has some advice. As far as I can tell, when I push a standard iostream onto a filter, the filter holds on to a reference of it. If this happens inside a function, then when the function returns the iostream is freed, followed by the filter. In its destructor the filter tries to perform a flush/close and promptly segfaults, as it is trying to access the iostream which has just been freed. There is a set_auto_close() function I can call on the filter which sounds like it would do the trick, but it doesn't and according to the docs it's because it "does not prevent the Filters and Devices in the chain from being closed [flushed] automatically if the chain is complete at destruction." So is there any way I can prevent a filtering_stream from performing I/O in its destructor? Thanks, Adam.

1 1

[property tree][json]how to create empty array?
by Kulti 12 Mar '11

12 Mar '11

Hi, all! It's possible to get following output from boost::property_tree::json_parser::write_json ? { "id": "id", "method": "test_method", "params": [] } I know how to create array with some items, but when I try to create empty array, I've get "params": ""

3 3

temporary filenames
by Kraus Philipp 12 Mar '11

12 Mar '11

Hello, is there any implementation for creating temporary files names? I'm using tmpnam, but it can be dangerous. On posix systems I can use mkstemp. Is there any save implementation within the boost (perhaps in the iostreams)? Thanks Phil

2 2

boost-users@lists.boost.org
by Stephen Hewitt 12 Mar '11

12 Mar '11

I have recently upgraded to Boost 1.46 and am having trouble compiling the following simple program (Using Visual Studio 2005): // Error.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include <tchar.h> #include <iostream> #include <boost/property_tree/ptree.hpp> #include <boost/property_tree/json_parser.hpp> void Go() { boost::property_tree::ptree t; boost::property_tree::read_json(std::cin, t); } int _tmain(int argc, _TCHAR* argv[]) { Go(); return 0; } Here are the errors I get: 1>------ Build started: Project: Error, Configuration: Debug Win32 ------ 1>Compiling... 1>stdafx.cpp 1>Compiling... 1>Error.cpp 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(184) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1> c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(178) : while compiling class template member function 'boost::property_tree::json_parser::json_grammar<Ptree>::definition<Scanner>::definition(const boost::property_tree::json_parser::json_grammar<Ptree> &)' 1> with 1> [ 1> Ptree=boost::property_tree::ptree, 1> Scanner=scanner_t 1> ] 1> c:\libraries\boost_1_46_0\boost\spirit\home\classic\core\non_terminal\impl\grammar.ipp(279) : see reference to class template instantiation 'boost::property_tree::json_parser::json_grammar<Ptree>::definition<Scanner>' being compiled 1> with 1> [ 1> Ptree=boost::property_tree::ptree, 1> Scanner=scanner_t 1> ] 1> c:\libraries\boost_1_46_0\boost\spirit\home\classic\core\non_terminal\impl\grammar.ipp(298) : see reference to function template instantiation 'void boost::spirit::classic::impl::call_helper<0>::do_<result_t,definition_t,ScannerT>(RT &,DefinitionT &,const ScannerT &)' being compiled 1> with 1> [ 1> ScannerT=scanner_t, 1> RT=result_t, 1> DefinitionT=definition_t 1> ] 1> c:\libraries\boost_1_46_0\boost\spirit\home\classic\core\non_terminal\grammar.hpp(55) : see reference to function template instantiation 'boost::spirit::classic::match<boost::spirit::classic::nil_t> boost::spirit::classic::impl::grammar_parser_parse<0,boost::property_tree::json_parser::json_grammar<Ptree>,boost::spirit::classic::parser_context<>,ScannerT>(const boost::spirit::classic::grammar<DerivedT> *,const ScannerT &)' being compiled 1> with 1> [ 1> Ptree=boost::property_tree::ptree, 1> ScannerT=scanner_t, 1> DerivedT=boost::property_tree::json_parser::json_grammar<boost::property_tree::ptree> 1> ] 1> c:\libraries\boost_1_46_0\boost\spirit\home\classic\core\non_terminal\grammar.hpp(65) : see reference to function template instantiation 'boost::spirit::classic::match<boost::spirit::classic::nil_t> boost::spirit::classic::grammar<DerivedT>::parse_main<ScannerT>(const ScannerT &) const' being compiled 1> with 1> [ 1> DerivedT=boost::property_tree::json_parser::json_grammar<boost::property_tree::ptree>, 1> ScannerT=scanner_t 1> ] 1> c:\libraries\boost_1_46_0\boost\spirit\home\classic\core\scanner\impl\skipper.ipp(109) : see reference to function template instantiation 'boost::spirit::classic::match<boost::spirit::classic::nil_t> boost::spirit::classic::grammar<DerivedT>::parse<scanner_t>(const ScannerT &) const' being compiled 1> with 1> [ 1> DerivedT=boost::property_tree::json_parser::json_grammar<boost::property_tree::ptree>, 1> ScannerT=scanner_t 1> ] 1> c:\libraries\boost_1_46_0\boost\spirit\home\classic\core\scanner\impl\skipper.ipp(155) : see reference to function template instantiation 'boost::spirit::classic::parse_info<IteratorT> boost::spirit::classic::impl::phrase_parser<SkipT>::parse<IteratorT,DerivedT>(const IteratorT &,const IteratorT &,const ParserT &,const SkipT &)' being compiled 1> with 1> [ 1> IteratorT=It, 1> SkipT=boost::spirit::classic::alternative<boost::spirit::classic::alternative<boost::spirit::classic::space_parser,boost::spirit::classic::confix_parser<boost::spirit::classic::impl::string_as_parser::type,boost::spirit::classic::kleene_star<boost::spirit::classic::anychar_parser>,boost::spirit::classic::alternative<boost::spirit::classic::eol_parser,boost::spirit::classic::end_parser>,boost::spirit::classic::unary_parser_category,boost::spirit::classic::non_nested,boost::spirit::classic::is_lexeme>>,boost::spirit::classic::confix_parser<boost::spirit::classic::impl::string_as_parser::type,boost::spirit::classic::kleene_star<boost::spirit::classic::anychar_parser>,boost::spirit::classic::impl::string_as_parser::type,boost::spirit::classic::unary_parser_category,boost::spirit::classic::non_nested,boost::spirit::classic::is_lexeme>>, 1> DerivedT=boost::property_tree::json_parser::json_grammar<boost::property_tree::ptree>, 1> ParserT=boost::property_tree::json_parser::json_grammar<boost::property_tree::ptree> 1> ] 1> c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(312) : see reference to function template instantiation 'boost::spirit::classic::parse_info<IteratorT> boost::spirit::classic::parse<std::_Vector_iterator<_Ty,_Alloc>,DerivedT,boost::spirit::classic::alternative<A,B>>(const IteratorT &,const IteratorT &,const boost::spirit::classic::parser<DerivedT> &,const boost::spirit::classic::parser<boost::spirit::classic::alternative<A,B>> &)' being compiled 1> with 1> [ 1> IteratorT=It, 1> _Ty=Ch, 1> _Alloc=std::allocator<char>, 1> DerivedT=boost::property_tree::json_parser::json_grammar<boost::property_tree::ptree>, 1> A=boost::spirit::classic::alternative<boost::spirit::classic::space_parser,boost::spirit::classic::confix_parser<boost::spirit::classic::impl::string_as_parser::type,boost::spirit::classic::kleene_star<boost::spirit::classic::anychar_parser>,boost::spirit::classic::alternative<boost::spirit::classic::eol_parser,boost::spirit::classic::end_parser>,boost::spirit::classic::unary_parser_category,boost::spirit::classic::non_nested,boost::spirit::classic::is_lexeme>>, 1> B=boost::spirit::classic::confix_parser<boost::spirit::classic::impl::string_as_parser::type,boost::spirit::classic::kleene_star<boost::spirit::classic::anychar_parser>,boost::spirit::classic::impl::string_as_parser::type,boost::spirit::classic::unary_parser_category,boost::spirit::classic::non_nested,boost::spirit::classic::is_lexeme> 1> ] 1> c:\libraries\boost_1_46_0\boost\property_tree\json_parser.hpp(45) : see reference to function template instantiation 'void boost::property_tree::json_parser::read_json_internal<Ptree>(std::basic_istream<_Elem,_Traits> &,Ptree &,const std::string &)' being compiled 1> with 1> [ 1> Ptree=boost::property_tree::ptree, 1> _Elem=char, 1> _Traits=std::char_traits<char> 1> ] 1> c:\users\steve\documents\visual studio 2005\projects\error\error.cpp(13) : see reference to function template instantiation 'void boost::property_tree::json_parser::read_json<boost::property_tree::ptree>(std::basic_istream<_Elem,_Traits> &,Ptree &)' being compiled 1> with 1> [ 1> _Elem=char, 1> _Traits=std::char_traits<char>, 1> Ptree=boost::property_tree::ptree 1> ] 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(184) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(184) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(184) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(184) : error C2882: 'assertion' : illegal use of namespace identifier in expression 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(184) : error C3861: 'expect_object': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(185) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(185) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(185) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(185) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(185) : error C2882: 'assertion' : illegal use of namespace identifier in expression 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(185) : error C3861: 'expect_eoi': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(186) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(186) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(186) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(186) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(186) : error C2882: 'assertion' : illegal use of namespace identifier in expression 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(186) : error C3861: 'expect_objclose': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(187) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(187) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(187) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(187) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(187) : error C2882: 'assertion' : illegal use of namespace identifier in expression 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(187) : error C3861: 'expect_arrclose': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(188) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(188) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(188) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(188) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(188) : error C2882: 'assertion' : illegal use of namespace identifier in expression 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(188) : error C3861: 'expect_name': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(189) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(189) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(189) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(189) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(189) : error C2882: 'assertion' : illegal use of namespace identifier in expression 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(189) : error C3861: 'expect_colon': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(190) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(190) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(190) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(190) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(190) : error C2882: 'assertion' : illegal use of namespace identifier in expression 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(190) : error C3861: 'expect_value': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(191) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(191) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(191) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(191) : error C2872: 'assertion' : ambiguous symbol 1> could be 'boost::assertion' 1> or 'c:\libraries\boost_1_46_0\boost\spirit\home\classic\error_handling\exceptions.hpp(187) : boost::spirit::classic::assertion' 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(191) : error C2882: 'assertion' : illegal use of namespace identifier in expression 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(191) : error C3861: 'expect_escape': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(195) : error C3861: 'expect_object': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(196) : error C3861: 'expect_eoi': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(203) : error C3861: 'expect_objclose': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(209) : error C3861: 'expect_name': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(210) : error C3861: 'expect_colon': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(211) : error C3861: 'expect_value': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(218) : error C3861: 'expect_arrclose': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(224) : error C3861: 'expect_value': identifier not found 1>c:\libraries\boost_1_46_0\boost\property_tree\detail\json_parser_read.hpp(250) : error C3861: 'expect_escape': identifier not found 1>Build log was saved at "file://c:\Users\Steve\Documents\Visual Studio 2005\Projects\Error\Debug\BuildLog.htm" 1>Error - 57 error(s), 0 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

2 1

lambda : fabs( x - y )< eps
by er 12 Mar '11

12 Mar '11

I'm submitting this in case someone easily spots a less verbose representation of fabs( x - y )< eps than the one shown below and would like to share it. Using lambda (or variants) only (I know I can write my own functor class). Thanks. #include <cmath> #include <boost/function.hpp> #include <boost/lambda/bind.hpp> #include <boost/lambda/lambda.hpp> #include <boost/numeric/conversion/bounds.hpp> typedef boost::function<double(double)> f1_; typedef boost::function<double(double, double)> f2_; typedef boost::function<bool(double)> g_; double eps = boost::numeric::bounds<double>::smallest(); f2_ f2 = lambda::bind( f1_( fabs ), lambda::_1 - lambda::_2 ) ; g_ g = ( eps > lambda::_1 ); BOOST_ASSERT( lambda::bind( g, lambda::bind( f2, lambda::_1, lambda::_2 ) )( 0.0, 0 * eps ) ); BOOST_ASSERT( !lambda::bind( g, lambda::bind( f2, lambda::_1, lambda::_2 ) )( 0.0, eps ) );

3 3