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Re: [Boost-users] [shared_ptr] Is it possible for a shared_ptr to
by Max 30 Dec '08

30 Dec '08

Sorry, the solution I presented here is absolutely incorrect. Here is the corrected version. I've tested. //______________SOLUTION_CODE_______________ template<class T> class condition_selector : public std::unary_function<bool, T> { T true_, false_; public: condition_selector(T true__, T false__) : true_(true__), false_(false__) {} T operator()(bool condition) { return condition? true_ : false_; } }; // helper function template<class T> condition_selector<T> make_condition_selector(T true_, T false_) { return condition_selector<T>(true_, false_); } // if(CONDITION), I'll take care of deleting the ptr, or let it be otherwise #define DECLARE_PTR_AUTO_DELETOR_CONDITIONAL(CLASS, VAR_PTR, CONDITION)\ boost::scoped_ptr<CLASS> auto__deletor__for__ ## VAR_PTR (\ make_condition_selector(VAR_PTR, static_cast<CLASS*>(0))(CONDITION)) // I don;t know why this version, using lambda, does not work //#define DECLARE_PTR_AUTO_DELETOR_CONDITIONAL(CLASS, VAR_PTR, CONDITION)\ // boost::scoped_ptr<CLASS> auto__deletor__for__ ## VAR_PTR (\ // boost::lambda::ret<CLASS*>(boost::lambda::if_then_else(_1,\ // VAR_PTR, static_cast<CLASS*>(0)))(static_cast<bool>(CONDITION))) //____________APPLICATION____________ AcDbCircle *pFace =new AcDbCircle (AcGePoint3d::kOrigin, AcGeVector3d::kZAxis, 1.0) ; AcDbCircle *pLeftEye =new AcDbCircle (AcGePoint3d (0.33, 0.25, 0.0), AcGeVector3d::kZAxis, 0.1) ; AcDbCircle *pRightEye =new AcDbCircle (AcGePoint3d (-0.33, 0.25, 0.0), AcGeVector3d::kZAxis, 0.1) ; AcDbArc *pMouth =new AcDbArc (AcGePoint3d (0, 0.5, 0), 1.0, 3.141592 + (3.141592 * 0.3), 3.141592 + (3.141592 * 0.7)) ; // Set the color property. pFace->setColorIndex (2) ; pLeftEye->setColorIndex (5) ; pRightEye->setColorIndex (5) ; pMouth->setColorIndex (1) ; // add the entities to the new block table record es = pBlockTableRecord->appendAcDbEntity (pFace) DECLARE_PTR_AUTO_DELETOR(AcDbCircle, pFace, (es!=Acad::eOk)); if ( es != Acad::eOk ) { //delete pFace ; // all these 'delete ...' not needed any more ... //delete pLeftEye ; //delete pRightEye ; //delete pMouth ; pBlockTableRecord->erase () ; pBlockTableRecord->close () ; return (es) ; } pFace->close () ; // ... ... Sorry for the noise. B/Rgds Max ================================================================================ There seems to be a solution that can make the code a little bit cleaner and easier to maintain. #define DECLARE_PTR_AUTO_DELETOR(CLASS, VAR_PTR)\ boost::scoped_ptr auto__deletor__for__ ## VAR_PTR (VAR_PTR) AcDbCircle *pFace =new AcDbCircle (AcGePoint3d::kOrigin, AcGeVector3d::kZAxis, 1.0) ; AcDbCircle *pLeftEye =new AcDbCircle (AcGePoint3d (0.33, 0.25, 0.0), AcGeVector3d::kZAxis, 0.1) ; AcDbCircle *pRightEye =new AcDbCircle (AcGePoint3d (-0.33, 0.25, 0.0), AcGeVector3d::kZAxis, 0.1) ; AcDbArc *pMouth =new AcDbArc (AcGePoint3d (0, 0.5, 0), 1.0, 3.141592 + (3.141592 * 0.3), 3.141592 + (3.141592 * 0.7)) ; DECLARE_PTR_AUTO_DELETOR(AcDbCircle, pFace); DECLARE_PTR_AUTO_DELETOR(AcDbCirclep, LeftEye); DECLARE_PTR_AUTO_DELETOR(AcDbCircle, pRightEye); DECLARE_PTR_AUTO_DELETOR(AcDbArc, pMouth); // Set the color property. pFace->setColorIndex (2) ; pLeftEye->setColorIndex (5) ; pRightEye->setColorIndex (5) ; pMouth->setColorIndex (1) ; // add the entities to the new block table record if ( (es =pBlockTableRecord->appendAcDbEntity (pFace)) != Acad::eOk ) { //delete pFace ; // all these 'delete ...' not needed any more ... //delete pLeftEye ; //delete pRightEye ; //delete pMouth ; pBlockTableRecord->erase () ; pBlockTableRecord->close () ; return (es) ; } pFace->close () ; if ( (es =pBlockTableRecord->appendAcDbEntity (pLeftEye)) != Acad::eOk ) { //delete pLeftEye ; //delete pRightEye ; //delete pMouth ; pBlockTableRecord->erase () ; pBlockTableRecord->close () ; return (es) ; } pLeftEye->close () ; if ( (es =pBlockTableRecord->appendAcDbEntity (pRightEye)) != Acad::eOk ) { //delete pRightEye ; //delete pMouth ; pBlockTableRecord->erase () ; pBlockTableRecord->close () ; return (es) ; } pRightEye->close () ; if ( (es =pBlockTableRecord->appendAcDbEntity (pMouth)) != Acad::eOk ) { //delete pMouth ; pBlockTableRecord->erase () ; pBlockTableRecord->close () ; return (es) ; } pMouth->close () ; Thanks you all that hepled. B/Rgds Max ------------------------------------------------------------------- 新浪空间——与朋友开心分享网络新生活！(http://space.sina.com.cn/ )

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Re: [Boost-users] [Serialization]Can not export polymorphic types
by Daniel Roberts 30 Dec '08

30 Dec '08

Yes, I understand that. I am sorry I should have been more clear; the base class is abstract. I am able to get the "unregistered class" exception in test_no_rtti.cpp, in load_derived, by removing the serializations using derived class pointers (which register the classes). When execution tries to serialize using the base class pointer, the "unregistered class" exception is thrown. I expect this to not happen because all the classes are registered using BOOST_CLASS_EXPORT. Could BOOST_CLASS_EXPORT not be working? Do you see this when commenting out the derived class serializations in load_derived? Thanks, Daniel Roberts Only polymophic types can be serialized through a base class pointer. Robert Ramey

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Re: [Boost-users] Boost.Lambda, boost::lambda::detail::return_type_deduction_failure?
by stefys 30 Dec '08

30 Dec '08

I have managed to fix this by using ret<>() to specify the type that I want my lambda function to return. Now I have: for_each(vect.begin(), vect.end(), var(str) += ret<string>(_1+constant(", ")) ); And it compiles and works fine.

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Re: [Boost-users] [test] Runtime parameter handling subsystem updated
by Georg Sauthoff 30 Dec '08

30 Dec '08

On 2008-12-24, Gennadiy Rozental <rogeeff(a)gmail.com> wrote: Hi, > I've checked in an update to the runtime parameters handling subsystem. > It's not completely up to my liking yet, but should fare better than old > one. [..] > New command line arguments parser allows: [..] > d) New parameter --help,-? is supported that produces help message with > usage information. Note that usage information is being printed also in > case there was error parsing command line. great, about missing --help and silent parsing of misspelled test options I stumbled across in older version of the utf. > Any comments and suggestions appreciated, Does your runtime parameter sybsystem use the boost program options library? Best regards Georg Sauthoff

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Boost.Lambda, boost::lambda::detail::return_type_deduction_failure?
by stefys 29 Dec '08

29 Dec '08

Hello, I've been trying to use Boost.Lambda in one of my simple applications, but I can't seem to get the following code to compile: for_each(vect.begin(), vect.end(), (var(str) += _1+constant(string(", ")) )); Where vect is a std::vector<std::string> and str is a std::string. I have included these headers: <boost/lambda/lambda.hpp>, <vector>, <string>, <algorithm>. Here is the complete error I'm getting (using MSVC2005): c:\program files\boost\boost_1_36_0\boost\lambda\detail\operator_lambda_func_base.hpp(225) : error C2679: binary '+=' : no operator found which takes a right-hand operand of type 'boost::lambda::detail::return_type_deduction_failure<<unnamed-symbol>>' (or there is no acceptable conversion) with [ <unnamed-symbol>=boost::lambda::detail::return_type_2_arithmetic_phase_3<std::basic_string<char,std::char_traits<char>,std::allocator<char>>,std::basic_string<char,std::char_traits<char>,std::allocator<char>>> ] f:\microsoft visual studio 8\vc\include\xstring(890): could be 'std::basic_string<_Elem,_Traits,_Ax> &std::basic_string<_Elem,_Traits,_Ax>::operator +=(const std::basic_string<_Elem,_Traits,_Ax> &)' with [ _Elem=char, _Traits=std::char_traits<char>, _Ax=std::allocator<char> ] f:\microsoft visual studio 8\vc\include\xstring(895): or 'std::basic_string<_Elem,_Traits,_Ax> &std::basic_string<_Elem,_Traits,_Ax>::operator +=(const _Elem *)' with [ _Elem=char, _Traits=std::char_traits<char>, _Ax=std::allocator<char> ] f:\microsoft visual studio 8\vc\include\xstring(900): or 'std::basic_string<_Elem,_Traits,_Ax> &std::basic_string<_Elem,_Traits,_Ax>::operator +=(_Elem)' with [ _Elem=char, _Traits=std::char_traits<char>, _Ax=std::allocator<char> ] while trying to match the argument list '(std::string, boost::lambda::detail::return_type_deduction_failure<<unnamed-symbol>>)' with [ <unnamed-symbol>=boost::lambda::detail::return_type_2_arithmetic_phase_3<std::basic_string<char,std::char_traits<char>,std::allocator<char>>,std::basic_string<char,std::char_traits<char>,std::allocator<char>>> ] c:\program files\boost\boost_1_36_0\boost\lambda\detail\lambda_functors.hpp(148) : see reference to function template instantiation 'RET boost::lambda::lambda_functor_base<Act,Args>::call<std::basic_string<_Elem,_Traits,_Ax>&,A,const boost::tuples::null_type,const boost::tuples::null_type,const boost::tuples::null_type>(A &,B &,C &,Env &) const' being compiled with [ RET=std::basic_string<char,std::char_traits<char>,std::allocator<char>> &, Act=boost::lambda::arithmetic_assignment_action<boost::lambda::plus_action>, Args=boost::tuples::tuple<std::basic_string<char,std::char_traits<char>,std::allocator<char>> &,boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda::arithmetic_action<boost::lambda::plus_action>,boost::tuples::tuple<boost::lambda::lambda_functor<boost::lambda::placeholder<1>>,boost::lambda::lambda_functor<boost::lambda::identity<const std::basic_string<char,std::char_traits<char>,std::allocator<char>>>>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>, _Elem=char, _Traits=std::char_traits<char>, _Ax=std::allocator<char>, A=std::basic_string<char,std::char_traits<char>,std::allocator<char>>, B=const boost::tuples::null_type, C=const boost::tuples::null_type, Env=const boost::tuples::null_type ] f:\microsoft visual studio 8\vc\include\algorithm(29) : see reference to function template instantiation 'std::basic_string<_Elem,_Traits,_Ax> &boost::lambda::lambda_functor<T>::operator ()<std::basic_string<_Elem,_Traits,_Ax>>(A &) const' being compiled with [ _Elem=char, _Traits=std::char_traits<char>, _Ax=std::allocator<char>, T=boost::lambda::lambda_functor_base<boost::lambda::arithmetic_assignment_action<boost::lambda::plus_action>,boost::tuples::tuple<std::basic_string<char,std::char_traits<char>,std::allocator<char>> &,boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda::arithmetic_action<boost::lambda::plus_action>,boost::tuples::tuple<boost::lambda::lambda_functor<boost::lambda::placeholder<1>>,boost::lambda::lambda_functor<boost::lambda::identity<const std::basic_string<char,std::char_traits<char>,std::allocator<char>>>>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>, A=std::basic_string<char,std::char_traits<char>,std::allocator<char>> ] c:\documents and settings\stefan\my documents\visual studio 2005\projects\simple\simple\simple.cpp(22) : see reference to function template instantiation '_Fn1 std::for_each<std::_Vector_iterator<_Ty,_Alloc>,boost::lambda::lambda_functor<T>>(_InIt,_InIt,_Fn1)' being compiled with [ _Fn1=boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda::arithmetic_assignment_action<boost::lambda::plus_action>,boost::tuples::tuple<std::basic_string<char,std::char_traits<char>,std::allocator<char>> &,boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda::arithmetic_action<boost::lambda::plus_action>,boost::tuples::tuple<boost::lambda::lambda_functor<boost::lambda::placeholder<1>>,boost::lambda::lambda_functor<boost::lambda::identity<const std::basic_string<char,std::char_traits<char>,std::allocator<char>>>>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>>, _Ty=std::string, _Alloc=std::allocator<std::string>, T=boost::lambda::lambda_functor_base<boost::lambda::arithmetic_assignment_action<boost::lambda::plus_action>,boost::tuples::tuple<std::basic_string<char,std::char_traits<char>,std::allocator<char>> &,boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda::arithmetic_action<boost::lambda::plus_action>,boost::tuples::tuple<boost::lambda::lambda_functor<boost::lambda::placeholder<1>>,boost::lambda::lambda_functor<boost::lambda::identity<const std::basic_string<char,std::char_traits<char>,std::allocator<char>>>>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>, _InIt=std::_Vector_iterator<std::string,std::allocator<std::string>> ] Yours sincerely, Steven

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[Serialization]Can not export polymorphic types
by Daniel Roberts 29 Dec '08

29 Dec '08

I made my own test program similar to test_no_rtti.cpp, only simpler. I have one base class and two classes that derive from it. All three classes are registered using BOOST_CLASS_EXPORT. I create an instance of each derived class and serialize them to an xml file. I then reload the file and try to serialize to a base class pointer and an "unregistered class" exception is thrown. I have stepped through my code and most of the boost serialization code and can not find a problem. The xml file looks good after creation but for some reason boost can not serialize it in properly. I have attached my short program. Can someone please tell me what I am doing wrong? Many thanks, Daniel Roberts

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Re: [Boost-users] [Serialization]Serializing from base class pointers clips derived class
by Daniel Roberts 29 Dec '08

29 Dec '08

Thanks for the response. Under closer inspection, the serialize calls are never made for either the derived classes or the base class when using a base class pointer. This is the xml output after save_derived is called: <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <rd1 class_id="0" tracking_level="1" version="0" object_id="_0"> <polymorphic_base class_id="1" tracking_level="0" version="0"></polymorphic_base> </rd1> <rd2 class_id="2" tracking_level="1" version="0" object_id="_1"> <polymorphic_base></polymorphic_base> </rd2> <rb1 class_id_reference="0" object_id_reference="_0"></rb1> <rb2 class_id_reference="2" object_id_reference="_1"></rb2> </boost_serialization> I am not sure where rb1 and rb2 tags come from since the serialize functions never get called. load_derived also does not call the serialize functions when using the base class pointers. I have attached the code I am using. It's identical to test_no_rtti.cpp except for two items. I do not have test_tools.hpp so I commented corresponding functions out and switched to std::ofstream/std::ifstream and xml_oarchive/xml_iarchive. Also, my target is a win32 console application. Please let me know if you have any ideas. Thanks, Daniel Roberts

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[mpl][variant] Visitor with typelists
by Tilo Nitzsche 29 Dec '08

29 Dec '08

What is the best (shortest/most elegant) way to create a visitor for a Variant, where there are subsets of the variant types, for which the operation is the same? typedef boost::mpl::vector<A, B, C> v1; typedef boost::mpl::vector<D, E> v2; typedef boost::mpl::joint_view<v1, v2> v; typedef boost::make_variant_over< v >::type v_union; struct visitor : public boost::static_visitor<int> { int operator()([T in v1] arg) { // do something for A, B, C return arg.a; } int operator()([T in v2] arg) { // do something for D, E return arg.b; } }; Thanks, Tilo

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[thread]Is shared_mutex recursive with respect to shared locks?
by Ken Savela 29 Dec '08

29 Dec '08

In other words, should the following code result in a deadlock? #include <iostream> #include <boost/thread.hpp> int main(int argc, char* argv[]) { boost::shared_mutex smx; boost::upgrade_lock<boost::shared_mutex> lock_one(smx); std::cout << "Locked once." << std::endl; std::cout.flush(); boost::upgrade_lock<boost::shared_mutex> lock_two(smx); std::cout << "Locked again." << std::endl; std::cout.flush(); boost::upgrade_to_unique_lock<boost::shared_mutex> lock_three(lock_two); std::cout << "Write lock." << std::endl; return 0; } This example illustrates the problem I'm having in my app -- I have a situation where a single thread may end up performing more than a single shared lock. When it does so, it hangs on the nested upgrade_lock. Is this the expected behavior?

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Lambda: Accessing fields of 'var'ed variable
by Swidan, Firas 29 Dec '08

29 Dec '08

Hi, I am trying to deal with the following situation: class tr { public: int i; int j; }; vector<tr> v(10); vector<uint> idx(5); for_each(idx.begin(), idx.end(), var(v)[_1].i = 1); This does not compile though, because lambda_functor has no member named i. My understanding is that I need the var before the v (also removing the var results in a compilation error). Am I on the right path? Thanks, Firas. ------------- Dr Firas Swidan, PhD Tel: +972.4.486.6278 E-mail: firas.swidan(a)intel.com<mailto:firas.swidan@intel.com> Intel Israel (74) Ltd. P.O.Box 1659, Haifa 31015, Israel --------------------------------------------------------------------- Intel Israel (74) Limited This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies.

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