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[string.algo] find_iterator, gives compile error in Boost 1.53
by gast128 06 Feb '13

06 Feb '13

Hello all, just dl Boost 1.53 and now I get a compile error in 'find_iterator' when using a forward iterator. Probably related to the change 'increment'. It now uses begin() + 1, and the + operator is not defined for the supplied iterator.

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Archive search
by Angelo Moscati 06 Feb '13

06 Feb '13

Hi, I would like to know if there is a way to search the archive before asking questions. Thanks, Angelo

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[program_options] Is it possible to change semantics after add_options() ?
by lukasz kucharski 06 Feb '13

06 Feb '13

Hello, I would like to ask if it is possible to change value_semantic associated with a program_option after it has been created ? I create `program_options` instance and populate it with add_options. Like in the examples provided by the documentation. I would like to change the semantics of a particular option later on. Is this even possible, or is this functionality deliberately disabled. I figured out that one can use options_description::find(), then strip it out `const`ness and dynamic cast to `typed_value_base` and use its methods. My motivation is such a design. I have a set of applications, which have a common subset of command line options/switches. However, they differ a bit in semantics. I.e. default value. I decided to refactor common parts into some `BasicApp` class and I thought I could move common options along with it as `boost::program_options` OO design should naturally support it. And it worked like a charm with `add_options` semantics to add new options. Up to the point I needed to change existing default values. Is there a proper way to do it ? Removing `const` constraint seems a bad approach since it looks like it's left there on purpose. Or my use-case is ill or hopeless. With regards, Łukasz.

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enable_shared_from_this()
by Dominique Devienne 06 Feb '13

06 Feb '13

Can someone please explain why this code: struct Foo : boost::enable_shared_from_this<Foo> {}; Foo* p_foo = new Foo; boost::shared_ptr<Foo> ptr_foo(p_foo->shared_from_this()); is throwing? msvcr100d.dll!_CxxThrowException(void * pExceptionObject, const _s__ThrowInfo * pThrowInfo) Line 157 C++ boost::throw_exception<boost::bad_weak_ptr>(const boost::bad_weak_ptr & e) Line 61 + 0x4d bytes C++ boost::detail::shared_count::shared_count(const boost::detail::weak_count & r) Line 421 + 0x23 bytes C++ boost::shared_ptr<`anonymous namespace'::Foo>::shared_ptr<`anonymous namespace'::Foo><`anonymous namespace'::Foo>(const boost::weak_ptr<`anonymous namespace'::Foo> & r) Line 216 C++ boost::enable_shared_from_this<`anonymous namespace'::Foo>::shared_from_this() Line 49 + 0xf bytes C++ > `anonymous namespace'::test_method() Line 41 + 0xf bytes C++ Since Foo embeds a weak_ptr, why can't it new the pi_ on the spot? (I'm using Boost 1.44). Thanks, --DD PS: On a related note, why doesn't boost::shared_ptr<Foo>(p_foo) (where p_foo is a raw Foo*) implicitly apply the aliasing Ctor, to share the same px, to avoid the classic bug of having several different pn on the same px, since p_foo derives from enable_shared_from_this()? Initially i thought that's what sp_enable_shared_from_this() and pe->_internal_accept_owner() were meant to do, but obviously that's not the case.

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Boost statechart design question
by sidharth shanbhag 05 Feb '13

05 Feb '13

Hi, I am designing an application using Boost statechart and needed some advice. I have multiple objects of the same type/functionality, however they are not related by an inheritance heirachy. The class types have a defined initialization sequence which move from 1 state to another. A few of these state initialization steps are the same eg. Resource X should be initialized as the second step in the sequence. But X can be initialized only once in the process. I am looking at doing the following: - Creating a statechart for every object, to manage its initialization. - Each state machine will maintain the pointer of the class object it has initialized. - A map of object Name -> State Machine will be created to ensure every object is initialized correctly. - Represent resource X as a separate state, which after its initialization will transition to the next state. Is there a potentially better way to do this considering: - There can be multiple objects of different class types - New objects can be added during runtime. Thanks, Sid

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How can I free memory allocated when deserializing with boost::archive::text_iarchive
by Adlai Shawareb 05 Feb '13

05 Feb '13

Thanks for your reply. Here is a code sample: std::istringstream istr; <* put data into istr here *> boost::archive::text_iarchive ia(istr_); Message* p_temp; ia & p_temp; mpBaseIncomingMessage = p_temp; // mpBaseIncomingMessage is of type (Message *) mpIncomingMessage = static_cast<SystemMessage*>(mpBaseIncomingMessage); // mpIncomingMessage is a pointer to a class derived from Message mObjectCallbackMap.process(mpIncomingMessage->mEvent); // execute a callback for this event delete mpIncomingMessage; // delete the allocated memory We then see a crash on either the " mObjectCallbackMap.process..." line or the " delete mpIncomingMessage", but only when certain actions are taken by the system. Any thoughts would be greatly appreciated. Regards, Adlai -----Original Message----- From: Boost-users [mailto:boost-users-bounces@lists.boost.org] On Behalf Of boost-users-request(a)lists.boost.org Sent: Monday, February 04, 2013 1:11 PM To: boost-users(a)lists.boost.org Subject: Boost-users Digest, Vol 3349, Issue 6 Send Boost-users mailing list submissions to boost-users(a)lists.boost.org To subscribe or unsubscribe via the World Wide Web, visit http://lists.boost.org/mailman/listinfo.cgi/boost-users or, via email, send a message with subject or body 'help' to boost-users-request(a)lists.boost.org You can reach the person managing the list at boost-users-owner(a)lists.boost.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Boost-users digest..." Today's Topics: 1. Re: Crediting the Work of Others (Bill Buklis) 2. How can I free memory allocated when deserializing with boost::archive::text_iarchive (Adlai Shawareb) 3. Re: in IOS, thread_info object is being destructed before the thread finishes executing (Nat Linden) 4. Re: Undirected version of dijkstra shortest path on directed graph. (Jeremiah Willcock) 5. Re: Crediting the Work of Others (Algocoders) 6. Re: How can I free memory allocated when deserializing with boost::archive::text_iarchive (Tim Moore) 7. [mpl::integral_c] Compiler Error with Visual Studio 2010 (Christian Henning) 8. Re: [mpl::integral_c] Compiler Error with Visual Studio 2010 (Nathan Crookston) ---------------------------------------------------------------------- Message: 1 Date: Mon, 04 Feb 2013 13:18:47 -0600 From: Bill Buklis <boostusr(a)pbjzone.com> To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] Crediting the Work of Others Message-ID: <51100997.1050909(a)pbjzone.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed On 2/1/2013 1:33 PM, Algocoders wrote: > Dave Abrahams <dave <at> boostpro.com> writes: > >> >> It has come to my attention that this book appears to use the work of >> others without attribution. I'd like to give the authors a chance to >> explain why that appearance is false. From what you can see in >> Amazon's limited preview of the book, one can find numerous instances >> of code lifted from Andrew Sutton's "origin" library. >> Some of the data structures have been renamed or had the case changed. >> Most of the duplication of Origin code comes in Chapter 7 in that >> book. There appear to be no references to Origin in that chapter >> (based on searching through the book in Amazon). >> >> The IndirectlyCopyable text includes unsourced quotes directly from >> http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3351.pdf >> without quotation, and the concepts* diagrams are taken from the same >> document. Is there an attribution on the previous page that we can't >> see from Amazon's limited preview? > Crediting the work of others have been done in the book as mentioned > in the links below: > Preface : > http://www.algocoders.com/sites/default/files/preface_foa_revised.pdf > Acknowledgement : > http://www/algocoders.com/sites/default/files/acknowledgement_foa.pdf > Table of Contents : > http://www.algocoders.com/sites/default/files/toc_foa_revised.pdf > > Chapter 3 : > http://www.algocoders.com/sites/default/files/chapter3_foa.pdf > Chapter 11 : > http://www.algocoders.com/sites/default/files/chapter11_foa.pdf > > We have avoided repetitive mention of original sources in respective > chapters to let not the content be littered with these details again. > Please let us know if we need to attribute in respective chapters too, > we would like to work on it. > Your feedback will be really helpful to guide us as a corrective measure. > > Looking forward for suggestions, > > Cheers, > Algocoders > Only the last link for Chapter 11 actually works and there aren't any acknowledgements presented in that pdf. -- Bill ------------------------------ Message: 2 Date: Mon, 4 Feb 2013 19:46:54 +0000 From: Adlai Shawareb <adlai(a)vytronus.com> To: "boost-users(a)lists.boost.org" <boost-users(a)lists.boost.org> Subject: [Boost-users] How can I free memory allocated when deserializing with boost::archive::text_iarchive Message-ID: <842DD0CD91745A48B9355924E2CF0BEA114FEF3D(a)VYTRONUS-SBS.vytronus.local> Content-Type: text/plain; charset="us-ascii" Hi, Does anyone know how we can free memory that is dynamically allocated by boost::archive::text_iarchive when deserializing an archive? We have tried using 'delete' and free() on the pointer when we finish with it, but it results in a crash. How does Boost dynamically allocate memory, 'new', 'malloc', or other? We tried a shared_ptr, but were getting compile errors related to the include files, and have not gone back to track that down. So if there is a simple way to free the memory that would be best for our application. Thanks, Adlai Shawareb Vytronus, Inc.

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Boost 1.53.0 released!
by Marshall Clow 04 Feb '13

04 Feb '13

Release 1.53.0 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This release contains five new libraries and numerous enhancements and bug fixes for existing libraries. New Libraries: * Atomic: C++11-style atomic<>, from Helge Bahmann, maintained by Tim Blechmann. * Coroutine: Coroutine library, from Oliver Kowalke. * Lockfree: Lockfree data structures, from Tim Blechmann. * Multiprecision: Extended precision arithmetic types for floating point, integer and rational arithmetic from John Maddock and Christopher Kormanyos. * Odeint: Solving ordinary differential equations, from Karsten Ahnert and Mario Mulansky. For details, including download links, see http://www.boost.org/users/news/version_1.53.0 You can also download directly from SourceForge: http://sourceforge.net/projects/boost/files/boost/1.53.0/ To install this release on your system, see http://www.boost.org/doc/libs/release/more/getting_started/index.html Thanks, --The Boost release team Beman Dawes Daniel James Eric Niebler Marshall Clow Rene Rivera Vladimir Prus

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[mpl::integral_c] Compiler Error with Visual Studio 2010
by Christian Henning 04 Feb '13

04 Feb '13

Hi there, shouldn't the following work: #include <boost\gil\gil_all.hpp> using namespace std; using namespace boost; int main() { typedef mpl::integral_c< unsigned char , numeric_limits< unsigned char >::max() > my_max_value_t; return 0; } Visual Studio 2010 gives me: error C2975: 'N' : invalid template argument for 'boost::mpl::integral_c', expected compile-time constant expression I'm a little surprised that this isn't working. Thanks, Christian

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How can I free memory allocated when deserializing with boost::archive::text_iarchive
by Adlai Shawareb 04 Feb '13

04 Feb '13

Hi, Does anyone know how we can free memory that is dynamically allocated by boost::archive::text_iarchive when deserializing an archive? We have tried using 'delete' and free() on the pointer when we finish with it, but it results in a crash. How does Boost dynamically allocate memory, 'new', 'malloc', or other? We tried a shared_ptr, but were getting compile errors related to the include files, and have not gone back to track that down. So if there is a simple way to free the memory that would be best for our application. Thanks, Adlai Shawareb Vytronus, Inc.

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A cool book for c++11 is Published now (Revised Edition)
by Algocoders . 04 Feb '13

04 Feb '13

Hi All, Revised edition of the book : "Foundation of Algorithms in C++11, Volume 1(Revised Edition): Using and Extending C++11, Boost And Beyond" : is available now. @Amazon: http://www.amazon.com/Foundation-Algorithms-Volume-Revised-Edition/dp/14819… @Pothi.com (Indian Edition): http://pothi.com/pothi/book/chandra-shekhar-kumar-foundation-algorithms-c11… This book is vital to understand and extend the C++11 Algorithms by carefully worked out synthesis of language and library features with an eye at future evolution with special emphasis to : - Template Alias - constexpr - copy_backward - requires - std::enable_if : SFINAE - Private Cast - Type Functions - Type Traits - Explicit Template Instantiations and Specializations - Trailing Return Type - auto type specifier - Intermediate Traits Idiom - Value Type Deduction Framework Table of Contents : http://algocoders.com/sites/default/files/toc_foa_revised.pdf Sample Chapter : http://algocoders.com/sites/default/files/chapter1_foa_revised.pdf For more details, please visit the link : http://www.algocoders.com/article/books Have Fun ! Cheers, Algocoders http://www.algocoders.com

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