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SQL library with full embedded SQL-syntax
by Dmitri Lyfar 19 Mar '07

19 Mar '07

Hi I would like to participate in Google Summer of Code in this year. I reviewed boost projects for last years and found an interesting project, I think. If you go to the link below you will see a short description for that library: http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl?Google_Summe… The goal of this post is to define the main library features, which will be useful for users. Is that library useful for C++ community? If you are using(or have ever used) similar C++ libraries for work with SQL: which of features do you want to have? Also I want to notice one of the biggest beauty of that approach: you can get the compiler to type-check the SQL-expression, what do you think about that? Thank you. Best regards, Lyfar Dmitriy

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[ping] The review of Intrusive library started March 12
by Joaquín Mª López Muñoz 19 Mar '07

19 Mar '07

As we approach the mid review of Ion Gaztañaga's Intrusive library, I would like to encourage you to consider submitting your review reports. So far we've received three reviews only, I hope more Boost members step in and contribute to this global effort which constitutes the cornerstone of Boost renowned quality standards. If you love and use Boost, remember that active involvement is a nice way of repaying the benefit you have obtained from this community. If you plan to submit a review before the deadline but are still working on it, I'd appreciate receiving a short notice so that I can estimate the final number of reviewers. Also, if you'd like to do a review but can't do it on time, please let me know so as to consider the possibility to ask for a period extension. The Review Manager, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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[fusion] How to create an object of my fusion generated type?
by Christian Henning 19 Mar '07

19 Mar '07

Hi there, I'm still playing with my vector of types example. Please see what I'm doing: #include <vector> #include <boost/mpl/assert.hpp> #include <boost/mpl/equal.hpp> #include <boost/mpl/list.hpp> #include <boost/mpl/transform.hpp> #include <boost/fusion/algorithm/transformation/transform.hpp> #include <boost/fusion/algorithm/iteration/for_each.hpp> #include <boost/fusion/sequence/adapted/mpl.hpp> #include <boost/fusion/sequence/container.hpp> #include <boost/fusion/sequence/conversion/as_list.hpp> using namespace std; using namespace boost; template <typename T> struct add_vector { typedef std::vector<T> type; }; struct A; struct B; struct C; struct create_empty_vec { template< class T > void operator()( T& t ) const { return std::vector<T>(); } }; struct add_one { template< class T > void operator()( T& vec ) const { vec.push_back( T() ); } }; int main() { typedef mpl::list< A, B, C > _types_; typedef mpl::transform1< _types_, add_vector<mpl::_1> >::type _mpl_list_of_vectors_; typedef fusion::result_of::as_list<_mpl_list_of_vectors_>::type _fusion_list_of_vectors_; _fusion_list_of_vectors_ vectors; fusion::for_each( vectors, create_empty_vec() ); return 0; } I have no idea why this code doesn't compile. My compiler (VC7.1) complaints: test.cpp C:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\vector(795) : error C2036: 'std::vector<_Ty>::pointer' : unknown size with [ _Ty=boost::mpl::aux::resolve_bind_arg<boost::mpl::bind1<boost::mpl::quote1<add_vector,boost::mpl::void_>,boost::mpl::lambda<boost::mpl::_1,boost::mpl::void_>::result_>::apply<boost::mpl::aux::resolve_bind_arg<boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>::apply<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::bkwd_state3,boost::mpl::deref<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::iter2>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na>::a1,boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boos t::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::bkwd_state3,boost::mpl::deref<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::iter2>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na>::type>::a1,boost::mpl::aux::resolve_bind_arg<boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>::apply<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::bkwd_state3,boost::mpl::deref<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_ tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::iter2>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na>::a1,boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::bkwd_state3,boost::mpl::deref<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::iter2>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na,boost::mpl::na>::type ] C:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\vector(791) : while compiling class-template member function 'void std::vector<_Ty>::_Tidy(void)' with [ _Ty=boost::mpl::aux::resolve_bind_arg<boost::mpl::bind1<boost::mpl::quote1<add_vector,boost::mpl::void_>,boost::mpl::lambda<boost::mpl::_1,boost::mpl::void_>::result_>::apply<boost::mpl::aux::resolve_bind_arg<boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>::apply<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::bkwd_state3,boost::mpl::deref<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::iter2>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na>::a1,boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::m pl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::bkwd_state3,boost::mpl::deref<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::iter2>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na>::type>::a1,boost::mpl::aux::resolve_bind_arg<boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>::apply<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::bkwd_state3,boost::mpl::deref<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mp l::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::iter2>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na>::a1,boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::bkwd_state3,boost::mpl::deref<boost::mpl::aux::reverse_fold_impl<3,boost::mpl::begin<_types_>::type,boost::mpl::end<_types_>::type,boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::state,boost::mpl::bind2<boost::mpl::lambda<boost::mpl::inserter<boost::mpl::clear_impl<boost::mpl::aux::list_tag>::apply<_types_>::type,boost::mpl::push_front<boost::mpl::na,boost::mpl::na>>::operation>::type,boost::mpl::_1,boost::mpl::bind1<boost::mpl::lambda<add_vector<boost::mpl::_1>>::type,boost::mpl::_2>>,boost::mpl::arg<1>>::iter2>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na>::type,boost::mpl::na,boost::mpl::na,boost::mpl::na,boost::mpl::na>::type [snip] Any help is appreciated, Christian

1 1

Boost Conference Reminder
by David Abrahams 19 Mar '07

19 Mar '07

Just a quick note to remind you that the official website for BoostCon'07 is up and registration is open: http://www.boostcon.com Space is limited, so register early to be sure you'll get in. See http://www.boostcon.com/registration for registration information. I'm really thrilled at the quality of the program (http://www.boostcon.com/program) we've assembled. On most days I'm going to have a hard time choosing among the simultaneous sessions! I look forward spending a week with you, immersed in Boost, at one of the most beautiful meeting sites in the world (http://www.boostcon.com/location/site) See you at BoostCon! -- Dave Abrahams Boost Consulting www.boost-consulting.com

1 0

[fusion] How to use transform Metafunction?
by Christian Henning 19 Mar '07

19 Mar '07

Hi there, since there is no example in the docs and no test for it. I was wondering how to use fusion's transform metafunction. Here is what I want to do. template <typename T> struct add_vector { typedef std::vector<T> type; }; struct A; struct B; struct C; int main() { typedef fusion::list< A, B, C > types; typedef fusion::transform< types, add_vector<> >::type vector_of_types; return 0; } The compiler is complaining that there are too few parameters for add_vector. In MPL you would just add _1 as the template parameter. But this doesn't work for fusion. So, how do I use it? Thanks, Christian

3 5

[lexical_cast] lexical_cast<int>("1e4") == 1
by n.torrey.pines＠gmail.com 19 Mar '07

19 Mar '07

lexical_cast<int>("1e4") == 1 // because of the way streams work of course I think that in the interests of robustness, and unless a better solution can be found, lexical_cast<> should be secialized for some types. Another solution might be to make sure that the whole string argument got consumed (rejecting things like "123 " )

5 4

which type of smart pointer to use?
by Vaclav 19 Mar '07

19 Mar '07

Hello, When I reset the main pointer to an object, I want all other pointers pointing to that object to be reset as well. Which type of smart pointer should I use? Example: boost::shared_ptr<MySillyClass> mySharedPtr1(new MySillyClass("test")); boost::shared_ptr<MySillyClass> mySharedPtr2 = mySharedPtr1; mySharedPtr1.reset(); if(mySharedPtr2.use_count() > 0) { TRACE("still used\n"); } else { TRACE("not used anymore\n"); } I am getting message "still used". I understand that is the normal behavior of boost::shared_ptr. Is there a smart pointer type that would print the second message? Reason: When I am done with an object, I would reset the main pointer to it and do not want other references to that object to be able to do anything with it. Thanks for advice! Vaclav

3 3

MPL map error on g++
by Santosh Joseph 18 Mar '07

18 Mar '07

My code compiles on visual studio 8, but on g++ 3.3.2 (linux) and with g++ 3.4.4 (cygwin) it chokes with the following error: In function `void convertToScctsOpt()': optionmanager.cpp:119: error: expected init-declarator before "ScctsType" optionmanager.cpp:119: error: expected `, ' or `;' before "ScctsType" optionmanager.cpp:120: error: `ScctsType' undeclared (first use this function) Is some special command line argument needed? thanks for any help. #define BOOST_MPL_CFG_NO_PREPROCESSED_HEADERS #define BOOST_MPL_LIMIT_MAP_SIZE 50 #include <boost/mpl/map.hpp> #include <boost/mpl/at.hpp> #include <boost/mpl/pair.hpp> namespace bm = boost::mpl; typedef bm::map< bm::pair<Type1, MappedType1>, . . . bm::pair<Type41, MappedType41> > TypeToTypeMap; template<typename SoapType> inline void convertToScctsOpt() { typedef bm::at<TypeToTypeMap,SoapType>::type ScctsType; } ____________________________________________________________________________________ Now that's room service! Choose from over 150,000 hotels in 45,000 destinations on Yahoo! Travel to find your fit. http://farechase.yahoo.com/promo-generic-14795097

2 1

Boost.Interprocess shared_memory.hpp
by Jean-Christophe Roux 17 Mar '07

17 Mar '07

Hello, I installed boost-1_35 this morning from cvs, which I believe contains the interprocess library. I took the interprocess doc from the vault. In the doc, there is at the end of the chapter "Shared Memory" a "Simple Example" that I am unable to compile because it contains the line: #include <boost/interprocess/shared_memory.hpp> but that file does not exist in my boost-1_35 folder. In /usr/local/include/boost-1_35/boost/interprocess, I have managed_shared_memory.hpp shared_memory_object.hpp but no shared_memory.hpp Maybe I am missing something obvious... Maybe the library from 1_35 and the docs from the vault are not compatible? Thanks for helping me out here. Jean-Christophe

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[boost-users][quickbook] Trying to get many sections onto one page
by Darren Garvey 17 Mar '07

17 Mar '07

Hello, I have a situation like this: [section Section 1] ... [endsect] [section Section 2] ... [endsect] and I'd like the generated html to have the layout of an article document-type but for it all to lie on one page. Obviously cut/paste is easy enough, but I'm wondering what the correct way to do this automatically is. Regards, Darren

2 2