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[wave] Custom I/O handling (include paths, etc.)?
by Anteru 03 May '11

03 May '11

Hi, I'm trying to adopt Wave as my custom preprocessor for a project. So far, things work fine, but there is one problem with Wave: I need to override all I/O functions, in particular, reading from files and opening files. Reading is easily changed by the input policy, but I couldn't find a way to register an include handler hook. There's found_include_directive, but nothing that allows me to get in-between wave and the filesystem. In my case, I on-demand construct some data which I want to be able to #include (i.e. #include <generated>) and some files are stored in resources/compressed files (#include <zip/file.h>). My include handler can open them, but how can I tell Wave to ask my include handler whether it can find a file instead of using boost::filesystem? Cheers, Anteru

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[Review] Boost.Convert library has ended
by Edward Diener 03 May '11

03 May '11

The review period for the Boost.Convert library has officially ended. I will continue to read posts about the library while I make my review decision, so please do not stop discussing the library as appropriate because the review period has ended. I have received one personal request for a late review, and I am willing to accept any other requests for a late review to be made through Wednesday and posted to the mailing list, but I will not consider any other late review in my decision unless someone requests it of me personally. I know this is a fine line between an official review and just comments about what others have said before, but I need to make my decision based on some finite set of reviews and their subsequent discussion. I would like to thank everyone who has officially reviewed Boost.Convert as well as all who have made subsequent comments. The more input received, the easier it becomes for me as a reviewer to make a final decision. I would also like to thank the implementer of the Boost.Convert library, Vladimir Batov, for his willingness to address issues, answer criticism, and engage in discussion about his library. My review decision should be made and posted to the mailing list no later than by the end of Sunday, May 8.

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Pass data to states, in boost state chart
by jusva2010 03 May '11

03 May '11

Hi All, Is there any way I can pass data to state event handler? Any pointers really appreciated. Thanks in advance Justin -- View this message in context: http://boost.2283326.n4.nabble.com/Pass-data-to-states-in-boost-state-chart… Sent from the Boost - Users mailing list archive at Nabble.com.

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Adapt rule's attribute to my own Boost::Spirit::Qi
by Egor Popov 03 May '11

03 May '11

Hello, everyone. There is a problem of attribute transfomation: I need to transfom rule's generated attribute to my own structure. I tried to parse mathematical formula and store it in std::vector in reverse Polish notation. Formula have form: math = as_string(*digit) >> (alpha) >> +(char_('+' | '-') >> math); rule<Iterator, std::string, space_type> math; Question #1: what type is it? I think that fusion::vector<std::string, char, std::vector<fusion::vector<char, std::string> > > but it seems it is not so. Question #2: how can I convert this structure, to mine (std::vector<std::string>)? -- View this message in context: http://boost.2283326.n4.nabble.com/Adapt-rule-s-attribute-to-my-own-Boost-S… Sent from the Boost - Users mailing list archive at Nabble.com.

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[Multi-index] : code fail to compile with VS2010 and boost 1.46.1. Proposed workaround
by Mathieu Peyréga 03 May '11

03 May '11

Hello, I had some code using boost 1.46.1 Multi-index library that used to compile and work very well with VS2008. I recently turned to VS2010 and some code is not compiling anymore. The problem is located in the boost_1_46_1\boost\multi_index\composite_key.hpp file and the compiler complains about not being able to distinguish between ambiguous overloads... I had to modify the composite_key.hpp file and have following changes : line 1001 : //return operator()(x,make_tuple(cref(y))); return operator()(x,make_tuple(boost::cref(y))); line 1036 : //return operator()(make_tuple(cref(x)),y); return operator()(make_tuple(boost::cref(x)),y); In order to explicitely add the boost namespace for cref. With those changes, it do compile and works very well. Can those changes in composite_key.hpp break something else ? Is there another workaround I would have missed ? I'm suspecting some conflict with new TR1 things i'm not very familiar with... Best regards, Mathieu Peyréga

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[Spirit][Date_Time] Parsing of boost date_time (segfault)
by Vitaly Budovski 03 May '11

03 May '11

Hi, I had a go at building a binary parser to output a date/time object. Unfortunately, I ran into some serious issues. One of my grammars causes the application to segfault when compiled with gcc, but not in clang. I'm not sure if this is a bug in gcc, boost, or simply a programming error. Please see attached file. Is there a better way to achieve what I need (final output should be ptime object)? All suggestions welcome :) Thanks, Vitaly

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[Serialization - 1.46.1] : Suggestion
by Mathieu Peyréga 03 May '11

03 May '11

Hello, Here is a small feature suggestion : I've been modifying the nvp.hpp file and added after line 142 the following macro definition : // Added by Mathieu Peyréga #define BOOST_SERIALIZATION_BASE_OBJECT_TEMPLATE_NVP(name,templateparameter) \ boost::serialization::make_nvp( \ BOOST_PP_STRINGIZE(name)BOOST_PP_STRINGIZE(templateparameter), \ boost::serialization::base_object<name<templateparameter> >(*this) \ ) // Which enables "easier" serialization for case like the following where the is multiple heritage and one of the base class is a template. Do you think this is the good way to go ? Best regards, Mathieu Peyréga /*************************************************************************************************** Short example of the BOOST_SERIALIZATION_BASE_OBJECT_TEMPLATE_NVP macro ***************************************************************************************************/ class C_Battery : public C_PhysicalElement, public C_GenericDatabaseObject<C_Battery> { public: C_Battery(void); C_Battery(C_Battery const& obj); C_Battery& operator=(C_Battery const& obj); virtual ~C_Battery(void); Boolean operator==(C_Battery const& other) const; Float64 getTensionPerElement(void) const; Float64 getCapacityPerElement(void) const; Float64 getFaradicEfficiency(void) const; Float64 getUnloadDeepness(void) const; Float64 getVolumicInstallationCost(void) const; Float64 getNumberOfCycles(void) const; Float64 getMonthlySelfLosses(void) const; void setTensionPerElement(Float64 const& value); void setCapacityPerElement(Float64 const& value); void setFaradicEfficiency(Float64 const& value); void setUnloadDeepness(Float64 const& value); void setVolumicInstallationCost(Float64 const& value); void setNumberOfCycles(Float64 const& value); void setMonthlySelfLosses(Float64 const& value); void loadFromCSVDatabase(C_CSVFileParser const& parser, Int32 recordIndex); protected: friend class C_GenericDatabaseObject<C_Battery>; Float64 m_TensionPerElement; // Tension par élément en Volts Float64 m_CapacityPerElement; // Capacitée par élément en A*h Float64 m_FaradicEfficiency; // Rendement faradique Float64 m_UnloadDeepness; // Profondeur de décharge Float64 m_VolumicInstallationCost; // Cout d'installation en euro/dm3 Float64 m_NumberOfCycles; // Nombre de cycles à la profondeur autorisée Float64 m_MonthlySelfLosses; // Auto décharge mensuelle friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(C_PhysicalElement); ar & BOOST_SERIALIZATION_BASE_OBJECT_TEMPLATE_NVP(C_GenericDatabaseObject,C_Battery); ar & BOOST_SERIALIZATION_NVP(m_TensionPerElement); ar & BOOST_SERIALIZATION_NVP(m_CapacityPerElement); ar & BOOST_SERIALIZATION_NVP(m_FaradicEfficiency); ar & BOOST_SERIALIZATION_NVP(m_UnloadDeepness); ar & BOOST_SERIALIZATION_NVP(m_VolumicInstallationCost); ar & BOOST_SERIALIZATION_NVP(m_NumberOfCycles); ar & BOOST_SERIALIZATION_NVP(m_MonthlySelfLosses); } }; BOOST_CLASS_VERSION(C_Battery, 1)

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Re: [Boost-users] Thread Safety of shared_ptr
by Kevin Frey 03 May '11

03 May '11

> shared_ptr< Session >* is not a shared ptr, it is a RAW ptr to shared_ptr< Session>. Yes, I know this. The pointer you call the RAW pointer is owned only by one object. It doesn't make the implementation wrong. My issue concerns the addref/decref behaviour that occurs simultaneously within two different threads.

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Re: [Boost-users] Thread Safety of shared_ptr
by 乔志强 03 May '11

03 May '11

shared_ptr< Session >* sp_Session = new shared_ptr< Session >( new Session ); shared_ptr< Session >* is not a shared ptr, it is a RAW ptr to shared_ptr< Session>. So you should: 1. use shared_ptr of shared_ptr: shared_ptr<shared_ptr< Session > > sp_Session ( new shared_ptr< Session >( new Session )) ; 2. or use shared_ptr directly: shared_ptr< Session > sp_Session( new Session ); I think you should use 2. > ------------------------------ > > Message: 7 > Date: Tue, 3 May 2011 10:46:39 +1000 > From: "Kevin Frey" <kfrey(a)hardcat.com> > To: <boost-users(a)lists.boost.org> > Subject: Re: [Boost-users] Thread Safety of shared_ptr > Message-ID: > <95C19A2ED65BF54CB79DF1F9D6A488E0013E3351(a)hcmail1.MEL01.hardcat.com.a > u> > > Content-Type: text/plain; charset="us-ascii" > > > Actually, I am not sure with this statement. Destructor is only called > if shared count reaches zero. I don't think that this can happen, that a > dtor is called in one thread and the other thread is still able to > increment the shared count even from the weak_ptr. I remember reading > weak_ptr's source and saw that it is also protected again such a case. > > > > I have taken the example at face value, but in hindsight the examples > could be a lot better because there is no context to describe the > circumstances of how the shared_ptrs are instantiated. > > > > For example, is p allocated globally, and p2 & p3 allocated at the > beginning of their respective threads? If so, example 4 becomes > meaningless because Thread B cannot force p2 out of scope since it would > only go out of scope once thread A exits, since thread A controls the > scope of p2. If thread B were to force p2 "out of scope" then p2 would > have to be a shared_ptr< >*, dynamically allocated., and subsequently > deleted by Thread B. But it is not represented that way. > > > > Unfortunately none of this helps solve my original question, which given > the direction this thread is proceeding, I will re-state in pseudo-code > that approximates the *actual* situation occurring in my program: > > > > Earlier on: > > > > shared_ptr< Session >* sp_Session = new shared_ptr< Session >( new > Session ); > > > > Dependent_Class* dep = new Dependent_Class( shared_ptr< Session >& > shared_ptr_session ); > > In Dependent_Object::Dependent_Object( ) > > this->sp_Session = new shared_ptr< Session >( shared_ptr_session ); > > Now, simultaneously: > > > > Thread A: > > Dependent_Class* dep2 = new Dependent_Class( shared_ptr< Session>& > shared_ptr_session ); > > In Dependent_Object::Dependent_Object( ) > > this->sp_Session = new shared_ptr< Session >( shared_ptr_session ); > > > > Thread B: > > In Dependent_Class::~Dependent_Class( ): // the cleanup of dep > > delete this->sp_Session; > > > > So, we have: > > > > 1. A shared object (pointed to by a shared_ptr) that is presently > in existence with a reference count of at least 2. > > 2. One thread A creating another shared_ptr to the shared object, > attempting to increment the reference count. > > 3. Another thread B simultaneously destroying a *different* > shared_ptr which is connected to the same underlying shared object, > decrementing the reference count. > > > > Note that the shared object is *not being destroyed* here, just the > reference counts are being manipulated. > > > > Will shared_ptr handle this situation correctly? > > > > Thanks > > > > Kevin > > >

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boost as shared library - linux
by Krzysztof 02 May '11

02 May '11

When I try to use libboost_program_options.so in my program it gives me a message: error while loading shared libraries: libboost_program_options.so.1.46.1: cannot open shared object file: No such file or directory I tried to do the command "ldconfig -n" and substitute to LD_LIBRARY_PATH the dir where it is located - the message remains the same. The boost library directory is in my home folder. How to overcome this? -- Regards Krzysztof J.

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