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

BOOST_STRONG_TYPEDEF
by Jono Poff 08 Aug '14

08 Aug '14

Hi, compiling this program with g++ 4.7.1 ... #include <boost/serialization/strong_typedef.hpp> BOOST_STRONG_TYPEDEF(uint32_t, LINKID_T) int main() { LINKID_T lid = 0xffddee33; return 0; } I get error: conversion from 'unsigned int' to non-scalar type 'LINKID_T' requested Looking at the header, the strong typedef struct defines assignment from uint32_t to LINKID_T ... D & operator=(const T & rhs) { t = rhs; return *this;} ... so what gives? Cheers, Jono -- ------------------------------ This email, including any attachments, is only for the intended recipient. It is subject to copyright, is confidential and may be the subject of legal or other privilege, none of which is waived or lost by reason of this transmission. If you are not an intended recipient, you may not use, disseminate, distribute or reproduce such email, any attachments, or any part thereof. If you have received a message in error, please notify the sender immediately and erase all copies of the message and any attachments. Unfortunately, we cannot warrant that the email has not been altered or corrupted during transmission nor can we guarantee that any email or any attachments are free from computer viruses or other conditions which may damage or interfere with recipient data, hardware or software. The recipient relies upon its own procedures and assumes all risk of use and of opening any attachments. ------------------------------

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BOOST_STRONG_TYPEDEF ...ps
by Jono Poff 08 Aug '14

08 Aug '14

Sorry, forgot to say Boost 1.55.0 Jono -- ------------------------------ This email, including any attachments, is only for the intended recipient. It is subject to copyright, is confidential and may be the subject of legal or other privilege, none of which is waived or lost by reason of this transmission. If you are not an intended recipient, you may not use, disseminate, distribute or reproduce such email, any attachments, or any part thereof. If you have received a message in error, please notify the sender immediately and erase all copies of the message and any attachments. Unfortunately, we cannot warrant that the email has not been altered or corrupted during transmission nor can we guarantee that any email or any attachments are free from computer viruses or other conditions which may damage or interfere with recipient data, hardware or software. The recipient relies upon its own procedures and assumes all risk of use and of opening any attachments. ------------------------------

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Geometry layout (packing) algorithm?
by Belcourt, Kenneth 07 Aug '14

07 Aug '14

Hi, I’m looking for an algorithm that will take a largish number (i.e. 10^5) 2d or 3d polygons (mostly parallel-pipeds, e.g. squares and boxes) and partition them into non-overlapping groups where each group contains some number of polygons that might abut along an edge or face, but not overlap. Each box can be represented by a collection of line segments so I thought geometry might have what I’m looking for but I didn’t see anything in a quick scan of the documentation. Does this so called packing (layout) algorithm sound like something already in Boost, Geometry or other library? I have an implementation but what looking to see what other options exist. Thanks. — Noel Belcourt

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[boost] [1.56.0] Release Candidate 3 available
by Marshall Clow 07 Aug '14

07 Aug '14

We've created a third release candidate to fix a one more issue with Boost.Range. The files for 1.56.0 RC3 are available at: http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. The files (and associated md5s) are: MD5 (./boost_1_56_0_rc3.7z) = b7a72a6a6f487fa445333b4e115c6171 MD5 (./boost_1_56_0_rc3.tar.bz2) = a744cf167b05d72335f27c88115f211d MD5 (./boost_1_56_0_rc3.tar.gz) = 8c54705c424513fa2be0042696a3a162 MD5 (./boost_1_56_0_rc3.zip) = fc16da21d641e03715a4144cb093964e Thanks! -- The release managers

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[date-time] boost::time_duration wrapping
by Justin Muncaster 07 Aug '14

07 Aug '14

Hello, I’m having issues with wrapping of boost::time_duration derived types. I can’t find anywhere in the documentation for when the time_duration types are supposed to wrap around. I have attached some sample source code below. The output is: SecCount = 80000000 is OK. Strange Stranger Problematic SecCount = 80000001 is STRANGE. I expect the output to be SecCount = 80000000 is OK. SecCount = 80000001 is OK. The problem we ran into had to do with seconds and milliseconds having different maximum permissible values. Any idea why boost::posix_time::seconds goes negative at 0x80000001 while milliseconds is not until much later? Thanks, Justin // // test.cpp // #include <boost/date_time.hpp> #include <iostream> using namespace std; using namespace boost::posix_time; //------------------------------------------------------- //------------------------------------------------------- void Strange(long SecCount) { long MilliCount = 1000 * SecCount; bool IsStrange = false; if (SecCount >= 0 && seconds(SecCount).is_negative()) { cout << "Strange" << endl; IsStrange = true; if (!milliseconds(MilliCount).is_negative()) { // If seconds wraps, why doesn't milliseconds? cout << "Stranger" << endl; IsStrange = true; } } if (seconds(SecCount) != milliseconds(MilliCount)) { cout << "Problematic" << endl; IsStrange = true; } if (!IsStrange) { cout << "SecCount = " << SecCount << " is OK." << endl; } else { cout << "SecCount = " << SecCount << " is STRANGE." << endl; } } //------------------------------------------------------- //------------------------------------------------------- int main() { cout << hex; Strange(0x80000000); Strange(0x80000001); return 0; }

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Re: [Boost-users] [ASIO] directory monitor ASIO extension
by Brian Wood 06 Aug '14

06 Aug '14

Niall Douglas writes > * Works reliably on Microsoft Windows (hard), Linux (slightly > easier), BSD and OS X (easiest by far of the lot). > I believe you. Having considered some of your previous comments in a different thread, on kqueue, I ported my code generator from Linux to BSD. I only found relief from a problem I was having by doing so. > Paul Kirth presented on this at C++ Now 2014. It is a surprisingly > tough engineering problem, and requires a design approaching ideal > for it to work at all. Are videos from that conference available yet? -- Brian Ebenezer Enterprises - In G-d we trust. http://webEbenezer.net

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[ASIO] directory monitor ASIO extension
by Szymon Gatner 06 Aug '14

06 Aug '14

Hi, I am going through code of directory monitor ASIO extension by Boris Schäling (http://www.highscore.de/boost/dir_monitor.zip) and I am wondering: what is the benefit of making this piece of code / library an ASIO extension. It just feels like it could be easier to use and implement if it wasn't? I hope I am missing something tho and looking here for enlightenment ;) Regards, Szymon Gatner

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why lockfree/queue.hpp requires has_trivial_assign and has_trivial_destructor to template type T
by 何子杰Hzj_jie 06 Aug '14

06 Aug '14

hi, all,as new to boost, i am looking for a solution to combine boost::lockfree::queue with std::function, i.e. boot::lockfree::queue<std::function>, but unfortunately, the implementation of the lockfree queue required the T to be trivial assignable and trivial destructible.with some basic investigation to the implementation of boost::lockfree::queue, the assignment operator is using when pop or unsynchronized_pop, it calls detail::copy_payload, which is using operator= or constructor and operator=. though overloaded assignment operator may use more time and cause the pop function to wait for longer time, i do not see it would block the logic.for the destruction, queue implementation always calls pool.template destruct instead deallocate, which means even for a default destructor, it will also be called. so is this a defect or by-design behavior of the lockfree queue? thank you in advanced. .Hzj_jie

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[msm] State Machine and Dependency Injection
by Kris 05 Aug '14

05 Aug '14

Hi, Recently I have implemented Dependency Injection library, which I proposed to boost last week (http://boost.2283326.n4.nabble.com/is-there-any-interest-in-a-dependency-in…) Right now I wanted to shared how dependency injection might be integrated with Boost.MSM (eUML) and would really glad for any feedback. Boost.MSM is a great library, unfortunately actions/guards have to have empty constructor and whole logic has to be handled via Finite State Machine. Such approach is hard to maintain and test, so would be great to have possibility to implement action/guards without FSM dependency and with proper dependency injection instead. More information: http://krzysztof-jusiak.github.io/di/boost/libs/di/doc/html/di/examples/int… Hello World: class guard : public euml_action<guard> { public: guard(shared_ptr<data> data = nullptr, shared_ptr<other_data> = nullptr); // default constructor is required by eUML template<typename TEvent> bool operator()(const TEvent&) const; // no FSM dependency }; class action : public euml_action<action> { public: action(shared_ptr<data> data = nullptr, shared_ptr<other_data> = nullptr); // default constructor is required by eUML template<typename TEvent> void operator()(const TEvent&); // no FSM dependency }; class state_machine_ : public state_machine_def<state_machine_> { public: using initial_state = state1; BOOST_MSM_EUML_DECLARE_TRANSITION_TABLE(( state1() + event() [guard()] / action() == state2() ), transition_table) }; using state_machine = back::state_machine< state_machine_ , back::use_dependency_injection // Boost.DI dependency injection policy >; auto sm = di::make_injector().create<state_machine>(); // create state machine / actions, guards and their dependencies will be injected via DI framework sm.process_event(event()); Hot it works? * we do implement actions/guards with any dependencies we need * we add use_dependency_injection policy in state machine definition * we create state machine using dependency injection framework library What MSM with DI actually give us? * actions/guards are really easy to test / code doesn't require FSM dependency - loosely coupled * signature change of actions/guards may not require binding configuration changes (if it's not an interface or it's an interface already bound) * FSM is just a declarative abstraction - we don't need to test it * we can use all DI goods for controlling how dependencies will be injected - see https://github.com/krzysztof-jusiak/di Project (with workings tests): https://github.com/krzysztof-jusiak/msm Comparison between usage of Boost.MSM with DI and without it: http://krzysztof-jusiak.github.io/di/boost/libs/di/doc/html/di/examples/int… Looking forward to hear from you. Any feedback is more than welcome. Cheers, Kris -- View this message in context: http://boost.2283326.n4.nabble.com/msm-State-Machine-and-Dependency-Injecti… Sent from the Boost - Users mailing list archive at Nabble.com.

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[1.56.0] Release candidates available
by Marshall Clow 04 Aug '14

04 Aug '14

Release candidate files for 1.65.0 are available at http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. The files (and associated md5s) are: MD5 (boost_1_56_0_rc1.7z) = 0ac22b92b24209286d48e4c41925cd9f MD5 (boost_1_56_0_rc1.tar.bz2) = 5b5bfa99244b1ac5737323decceb19c2 MD5 (boost_1_56_0_rc1.tar.gz) = 2047cdd4e09cda34e7f10fec0f821175 MD5 (boost_1_56_0_rc1.zip) = 0c544f6acc85550b15cdc9221f2ac0c9 Thanks! -- The release managers

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