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Implementation Of Natural Sort for C++
by Gagan Kumar 27 Dec '15

27 Dec '15

In Boost Trac, I found Natural Sort as Ticket #11021 (new Feature Requests). I too think it will be good for C++ to have it too. Thus I tried to make my Implementation on Natural Sort. Here, https://github.com/scopeInfinity/NaturalSort Can this be included in Boost extensions, or can you please guide me to make it better so that It can be included. Regards Gagan Kumar Natural Sort Example - Inputs : Hello 100 Hello 34 Hello 9 Hello 25 Hello 10 Hello 8 Normal Sort Output : Hello 10 Hello 100 Hello 25 Hello 34 Hello 8 Hello 9 Natural Sort Output : Hello 8 Hello 9 Hello 10 Hello 25 Hello 34 Hello 100 | | | | | | | | | | | scopeInfinity/NaturalSortNaturalSort - C++ Implementation of Natural Comparision and Natural Sort | | | | View on github.com | Preview by Yahoo | | | | |

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[multi_index] do erase() call key extractors?
by Nick Stokes 25 Dec '15

25 Dec '15

This is probably rather obvious, but I wasn't able to locate this guarantee in MIC docs. Take, struct Foo { explicit Foo(Bar* b = nullptr) : bar(b) {} Bar* bar; }; int getBarValue (const Foo& f) { assert( f.bar ); return f.bar->getValue(); } boost::multi_index< Foo, indexed_by< < hashed_unique < member<Foo, Bar* , &Foo::bar > >> , hashed_non_unique < global_fun<const Foo&, int, &getBarValue >> >> FooIndex; void grill() { FooIndex fooIndex; Bar* b; { auto bWork = make_unique<Bar>(); // ... fooIndex.emplace( bWork.get() ); b = bWork.get(); } fooIndex.erase(b); // ... } Please ignore the fact that raw-pointers are potentially dangerous etc. The question is does erase() call getBarValue() despite the fact I am using the first index? More generally, do key extractors get called *at all* except at the point of insertion? Thanks, Nick

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template error when using multi_index_container
by John M. Dlugosz 25 Dec '15

25 Dec '15

I'm getting a strange template instantiation error with a simple and reasonable use of multi_index_container, which I've written up in detail with a minimal program to reproduce here: http://stackoverflow.com/questions/34450642/why-is-this-member-function-a-d… This showed up in Visual Studio 2015, and has worked just fine for years on VS10 and on other platforms. I've tried updating Boost and new versions don't make any difference. This example was prepared using Boost 1.59, and I see the same thing with 1.60. —John

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[container] Boost 1.60 Release link error
by Hickman, Steve (AdvTech) 24 Dec '15

24 Dec '15

Getting a linker error with the Windows version of Boost on release only (not debug) using v 1.60. This did not show up with 1.58 (I skipped 1.59 so I have no comment on it). I'm using the prebuilt libraries: 8> Creating library D:\GITRepos\fd_x-current_feature\source\Devices\MockDevice\Test\Release\MockTest.lib and object D:\GITRepos\fd_x-current_feature\source\Devices\MockDevice\Test\Release\MockTest.exp 8>MockDevice.lib(Mock.obj) : error LNK2001: unresolved external symbol "public: void __thiscall boost::container::container_detail::has_member_function_named_construct<class boost::container::new_allocator<char> >::BaseMixin::construct(void)" (?construct@BaseMixin@?$has_member_function_named_construct@V?$new_allocator@D@container@boost@@@container_detail@container@boost@@QAEXXZ) 8>MockDevice.lib(Mock.obj) : error LNK2001: unresolved external symbol "public: void __thiscall boost::container::container_detail::has_member_function_named_construct<class boost::container::new_allocator<struct boost::container::container_detail::tree_node<struct std::pair<class boost::container::basic_string<char,struct std::char_traits<char>,class boost::container::new_allocator<char> > const ,struct boost::interprocess::ipcdetail::ref_count_ptr>,void *,0,1> > >::BaseMixin::construct(void)" (?construct@BaseMixin@?$has_member_function_named_construct@V?$new_allocator@U?$tree_node@U?$pair@$$CBV?$basic_string@DU?$char_traits@D@std@@V?$new_allocator@D@container@boost@@@container@boost@@Uref_count_ptr@ipcdetail@interprocess@3@@std@@PAX$0A@$00@container_detail@container@boost@@@container@boost@@@container_detail@container@boost@@QAEXXZ) 8>D:\GITRepos\fd_x-current_feature\source\Devices\MockDevice\Test\Release\MockTest.exe : fatal error LNK1120: 2 unresolved externals Steve Hickman System Architect, Human Machine Collaboration Honeywell | Aerospace Office: 480-236-8367 steve.hickman(a)honeywell.com https://in.honeywell.com/sites/aero/Pages/Home.aspx

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Boost 1.60 causes argument-dependent-lookup issues.
by John M. Dlugosz 24 Dec '15

24 Dec '15

See http://stackoverflow.com/questions/34449254/how-is-argument-dependent-looku… I found that code that has worked OK on previous versions of Boost (and does not have this issues with 1.59) is getting unexpected ambiguities in 1.60. Using boost::totally_ordered et al. (even as a private base) appears to be polluting the namespace in which the client class appears. Something like this: class C : boost::totally_ordered<C> { ⋯ } ; using std::make_shared; ⋮ auto p= make_shared<C>(args); this complains that it finds boost::make_shared via argument-dependent lookup, as well as the expected std::make_shared.

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Re: [Boost-users] Race in boost::condition_variable::wait
by Éric Malenfant 23 Dec '15

23 Dec '15

Not sure I understand your question. Unless I'm missing something, the guard in condition_variable::wait does not release the mutex, it is simply there to ensure that it is reacquired on exit. The mutex is released by pthread_cond_wait (atomically with the wait on the condition). Éric Malenfant Le 2015-12-22 8:30 PM, "Chris Stankevitz" <chrisstankevitz(a)gmail.com> a écrit : Hi, Regarding boost::condition_variable::wait (listed below with an obvious modification), It seems to me that there is a race condition because the following operations are not atomic: 1) unlocking of "m" 2) waiting on "cond". Can someone explain to me why boost::condition_variable::wait is not racing the user code in the example below? Thank you, Chris === inline void condition_variable::wait(unique_lock<mutex>& m) { int res=0; { thread_cv_detail::lock_on_exit<unique_lock<mutex> > guard; detail::interruption_checker check_for_interruption(&internal_mutex,&cond); guard.activate(m); #ifdef ENCOURAGE_DEADLOCK boost::this_thread::sleep_for(boost::chrono::seconds(100)); #endif do { res = pthread_cond_wait(&cond,&internal_mutex); } while (res == EINTR); } } === #define ENCOURAGE_DEADLOCK #include <boost/thread.hpp> int main() { boost::mutex Mutex; boost::condition_variable Condition; bool Quit = false; boost::thread Thread([&] { boost::unique_lock<boost::mutex> Lock(Mutex); while (!Quit) { Condition.wait(Lock); } }); boost::this_thread::sleep_for(boost::chrono::seconds(1)); boost::lock_guard<boost::mutex> Lock(Mutex); Quit = true; Condition.notify_all(); return 0; } _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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[boost][iterator] Regarding Ticket #11847
by Gagan Kumar 23 Dec '15

23 Dec '15

Hi, I am new and I wanted to contribute. The ticker #11847 says,"reference typedef no longer available in parent class of iterator_facade" but actually I think reference is available in class iterator_facade itself(boost/iterator/iterator_facade.hpp). But still we are not able to use reference in class simple_iterator : public boost::iterator_facade<simple_iterator<T>, T, boost::forward_traversal_tag> and then after a while I saw this http://stackoverflow.com/questions/1643035/propagating-typedef-from-based-t… >From my side I can only solve this kind of problem by using typename boost::iterators::iterator_facade<simple_iterator<T>, T, boost::iterators::forward_traversal_tag>::reference; or using alternative of reference as T& dereference() const { return *m_iter; } //T& instead of reference, as stated in Ticket Can somebody please tell me or guide me to a better way to solve this problem. Regards Gagan Kumar

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Boost 1.60.0 has been released
by Marshall Clow 23 Dec '15

23 Dec '15

Release 1.60.0 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 release contains one new library and numerous enhancements and bug fixes for existing libraries. New Libraries * VMD: Variadic Macro Data library, from Edward Diener For details, including download links, see http://www.boost.org/users/news/version_1.60.0 You can also download directly from SourceForge: http://sourceforge.net/projects/boost/files/boost/1.60.0/ Tom Kent has made pre-built windows binaries, and they are available at: https://sourceforge.net/projects/boost/files/boost-binaries/1.60.0/ 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 Vladimir Prus Rene Rivera Marshall Clow Eric Niebler Daniel James Beman Dawes

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Race in boost::condition_variable::wait
by Chris Stankevitz 23 Dec '15

23 Dec '15

Hi, Regarding boost::condition_variable::wait (listed below with an obvious modification), It seems to me that there is a race condition because the following operations are not atomic: 1) unlocking of "m" 2) waiting on "cond". Can someone explain to me why boost::condition_variable::wait is not racing the user code in the example below? Thank you, Chris === inline void condition_variable::wait(unique_lock<mutex>& m) { int res=0; { thread_cv_detail::lock_on_exit<unique_lock<mutex> > guard; detail::interruption_checker check_for_interruption(&internal_mutex,&cond); guard.activate(m); #ifdef ENCOURAGE_DEADLOCK boost::this_thread::sleep_for(boost::chrono::seconds(100)); #endif do { res = pthread_cond_wait(&cond,&internal_mutex); } while (res == EINTR); } } === #define ENCOURAGE_DEADLOCK #include <boost/thread.hpp> int main() { boost::mutex Mutex; boost::condition_variable Condition; bool Quit = false; boost::thread Thread([&] { boost::unique_lock<boost::mutex> Lock(Mutex); while (!Quit) { Condition.wait(Lock); } }); boost::this_thread::sleep_for(boost::chrono::seconds(1)); boost::lock_guard<boost::mutex> Lock(Mutex); Quit = true; Condition.notify_all(); return 0; }

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Not for publishing
by Soul Studios 22 Dec '15

22 Dec '15

To whoever it is that's been blocking my posts to the mailing list - with the exception of this email, please stop. I have chronic fatigue syndrome, and I feel like I'm fighting an uphill battle against the lack of documentation around actually doing documentation for boost. I would've understood if I'd said anything reasonably offensive, but I don't think I did.

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