December 2008 - Boost-users

Re: [Boost-users] [bind] Need Help - Function Composition
by loadcom 19 Dec '08

19 Dec '08

Hello Watanabe, Your code works well. And it's much more generic and elegant than the original version. Thank you so much! Best regards 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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boost test + MFC
by Andrew Wan 19 Dec '08

19 Dec '08

Does anyone know how to use boost test library with MFC programs? All the examples & documentation only covers CONSOLE programs. Would be good if there was an MFC example.

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Re: [Boost-users] [boost] tweaking the review process
by David Abrahams 19 Dec '08

19 Dec '08

on Wed Dec 17 2008, Fabio Fracassi <f.fracassi-AT-gmx.net> wrote: > David Abrahams schrieb: >> on Mon Dec 15 2008, John Phillips <phillips-AT-mps.ohio-state.edu> wrote: > [...] >>> I don't know if I was the first to do this, but I have done it. Looking at the >>> current contents of the instructions to review managers, either they have changed >>> since I started managing reviews or I somehow hallucinated extra words to add the > user >>> list to the lists that should receive an announcement of the review. >> >> An announcement is one thing; instructing people to post their reviews >> in the same list is a different thing entirely. >> > > You don't have to, it happens almost automatically if you are not > careful. Many people write their Review as a reply to the original > announcement, and if you are not extra careful to remove the user list > from the recipients your review gets send to both lists. The poster of the announcement should make it clear how to post a review. I never liked the idea of reviews showing up in the list with the subject "Review period for Boost.XXXX begins today" anyway. Also s/he can set the Reply-To: field. -- Dave Abrahams BoostPro Computing http://www.boostpro.com

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Re: [Boost-users] Building the Boost.Test fails
by Gennadiy Rozental 18 Dec '08

18 Dec '08

Maruvekere, Praveen (Contractor) wrote: > Hi Group, > > Any idea what should be the fix for this problem I know that the > template declaration in the class shown below may be problematic What is the version of Boost? What compiler r u using? What r u building? How do you run build? Gennadiy

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[multi_array] Create view at runtime
by loadcom 18 Dec '08

18 Dec '08

Hello, I'm using boost::multi_array of boost 1_36_0 with VS2003SP1. I hope I could determine the number of dimensions of a view of a given multi_array at runtime, or something like this: typedef boost::multi_array<int, 5> array_t; typedef typename array_t::index_range range_t; array_t array; // ... bool f; array_t::array_view<_>::type view = grid[boost::indices[f? range_t() : 11] [f? range_t(1,2): range_t()][rang_t]]; I'll be appreciated to have any kind of help. 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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[Boost.Graph] Accessing edge properties via an edge_iterator
by Julius Ziegler 18 Dec '08

18 Dec '08

Hello list, I wonder what is the fastest method to access edge properties of an adjacency_list when iterating over edges. Actually, the only way I know of for accessing properties is via operator[]: typedef boost::adjacency_list<listS, vecS, boost::directedS, NodeProperty, EdgeProperty > Graph; Graph g; for( tie( ei, ei_end ) = edges( graph ); ei != ei_end; ++ei ) { g[*ei]=something; } From this I conclude, that the right EdgeProperty is stored in some associative container, with edge_descriptor being the key-type. Or does edge_iterator store any information besides a pair<vertex_descriptor, vertex_descriptor>? What is the time complexity of this look_up? To me it feels that there should be a faster way to access properties via an edge_iterator, and by browsing the source I found that edge_iterator has a member function get_property(), however, since it returns void*, and I did not find anything in the documentation, I'm not sure if it is there for this purpose. Thank you very kindly for any hints, Julius

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[bind] Need Help - Function Composition
by loadcom 18 Dec '08

18 Dec '08

Hello all, I'm using boost::bind to get elegant code. Thank the author for the great lib. I'm posting because I ran accross a small problem with the following code. My intention of the code is to find the element of a container with the least abs value of a member (i_). template <typename Arg, typename Result> class less_by_func : public std::binary_function<Arg, Arg, bool> { typedef boost::function<Result(Arg)> fn_t; typedef less_by_func<Arg, Result> self_t; fn_t func_; less_by_func() {} // not open public: less_by_func(const self_t& src) : func_(src.func_) {} explicit less_by_func(const fn_t& func) : func_(func) {} template <typename Arg, typename Result> explicit less_by_func(const less_by_func<Arg, Result>& src) : func_(src.func_) {} bool operator()(const Arg& lhs, const Arg& rhs) const { return func_(lhs) < func_(rhs); } }; // helper function template<typename F> less_by_func<typename F::argument_type, typename F::result_type> make_less_by_func(F func) { return less_by_func<typename F::argument_type, typename F::result_type>(func); } struct A { int i_; A() : i_(0) {} explicit A(int i) : i_(i) {} void set(int i) { i_ = i; } int get() const { return i_; } }; std::vector<A> a_list; a_list.push_back(A(10)); a_list.push_back(A(222)); a_list.push_back(A(-100)); int min_abs = std::min_element(a_list.begin(), a_list.end(), min2max::make_less_by_func( boost::function<int(A)>( boost::bind<int>( std::ptr_fun(&std::abs<int>), boost::bind(&A::i_, _1) ) ) ) )->i_; std::cout << min_abs << std::endl; This code works fine, what I don't understand is why I couldn't remove the explicit construction of a boost::function<int(A)> object and let compiler do the implicit conversion(construction) silently. That means the following code doesn't work: int min_abs = std::min_element(a_list.begin(), a_list.end(), min2max::make_less_by_func( boost::bind<int>( std::ptr_fun(&std::abs<int>), boost::bind(&A::i_, _1) ) ) )->i_; The following code doesn't get compile neither: std::stable_sort(a_list.begin(), a_list.end(), make_less_by_func(boost::bind(&A::i_, _1))); I know a more verbose version like this will also work: int min_abs = std::min_element(a_list.begin(), a_list.end(), boost::bind(std::less(), boost::bind(std::ptr_fun(&std::abs), boost::bind(&A::i_, _1)), boost::bind(std::ptr_fun(&std::abs), boost::bind(&A::i_, _2)) ) )->i_; But I just want the code to be as elegant as possible. :-) My environment is: boost_1_36_0 + VS2003sp1 Thanks for any hints. with best regards 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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[process] How to exec multiple shell commands
by Konstantin Litvinenko 18 Dec '08

18 Dec '08

Hi! I have successfully used boost.process but now stuck with a problem. I need to execute 2 commands in one shell invocation. Both windows and linux allow do that, but I can't figure out how to do it with help of boost.process. Is there interface to do that? PS. I am using old boost.process. I have download process-is-0.4.zip from the vault and didn't find solution for my problem.

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Boost::thread and Dr. Watson
by Francesco Nesci 18 Dec '08

18 Dec '08

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Thread scope
by Birju Prajapati 18 Dec '08

18 Dec '08

Hi, I've seen that when a newly created thread goes out of scope, it keeps running - this suggests to me that they are heap allocated, but can't find anywhere in the documentation that confirms this. Can someone confirm or deny this, and show me where in the docs it is if confirmed? Many thanks, Birju Schneider Trading 4th Floor, 25 Copthall Avenue London EC2R 7BP -------------------------------------------------------- Message from: Birju.Prajapati(a)schneidertrading.com Message to: boost-users(a)lists.boost.org Attached files: 0 This e-mail and any files transmitted with it are confidential, may be legally privileged, and are for the sole use of the intended recipient. Copyright in this e-mail and any accompanying document created by us is owned by us. If you are not the intended recipient of this e-mail or any part of it please telephone our IT Department at the number shown above or by e-mail at info(a)schneidertrading.com. You should not use or disclose to any other person the contents of this e-mail or its attachments (if any), nor take copies. This e-mail is not a representation or warranty and is not intended nor should it be taken to create any legal relations, contractual or otherwise. Schneider Trading Associates Ltd (Registration No. 3692131) is incorporated in England and Wales and the registered office is at 25 Copthall Avenue, London EC2R 7BP. The company is authorised and regulated by the Financial Services Authority

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