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boost how to map between string and operation
by Jack Bryan 13 Jul '10

13 Jul '10

Dear All: I need to bind some strings with some operations boost map. For example, if inputString == "prepareDataVector1" dataVectorRegionRef = prepareDataVector1; loadDataVector.push_back("prepareDataVector1"); else inputString == "prepareDataVector2" dataVectorRegionRef = prepareDataVector2; loadDataVector.push_back("prepareDataVector2");else ... so on I have checked boost lib, map can do mapping of two class, I need to do mapping between string and operations. Any help is appreciated. Jack July 13 2010 _________________________________________________________________ Hotmail has tools for the New Busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:…

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Building 1.39 on aix5.3 xlc V9.0
by Joy Vincent 13 Jul '10

13 Jul '10

Built boost libraries ok. Am getting error when building my app. Here's the error: "/mnt/releases/boost/boost_1_35_0/aix53_64-xlc9-release/include/boost/filesystem/operations.hpp", line 789.72: 1540-1118 (S) The declaration of "end_itr" uses the undefined class "boost::filesystem::basic_directory_iterator<boost::filesystem::basic_path<std::basic_string<wchar_t,std::char_traits<wchar_t>,std::allocator<wchar_t> >,boost::filesystem::wpath_traits> >" when the class must be complete. "/mnt/releases/boost/boost_1_35_0/aix53_64-xlc9-release/include/boost/filesystem/operations.hpp", line 787.21: 1540-0700 (I) The previous message was produced while processing "boost::filesystem::detail::remove_all_aux<boost::filesystem::basic_path<std::basic_string<wchar_t,std::char_traits<wchar_t>,std::allocator<wchar_t> >,boost::filesystem::wpath_traits> >(const basic_path<std::basic_string<wchar_t,std::char_traits<wchar_t>,std::allocator<wchar_t> >,boost::filesystem::wpath_traits> &, file_status)". "/mnt/releases/boost/boost_1_35_0/aix53_64-xlc9-release/include/boost/filesystem/operations.hpp", line 495.28: 1540-0700 (I) The previous message was produced while processing "boost::filesystem::remove_all<boost::filesystem::basic_path<std::basic_string<wchar_t,std::char_traits<wchar_t>,std::allocator<wchar_t> >,boost::filesystem::wpath_traits> >(const basic_path<std::basic_string<wchar_t,std::char_traits<wchar_t>,std::allocator<wchar_t> >,boost::filesystem::wpath_traits> &)". "/mnt/releases/boost/boost_1_35_0/aix53_64-xlc9-release/include/boost/filesystem/operations.hpp", line 729.16: 1540-0700 (I) The previous message was produced while processing "boost::filesystem::remove_all(const wpath &)". "/mnt/releases/boost/boost_1_35_0/aix53_64-xlc9-release/include/boost/filesystem/operations.hpp", line 789.72: 1540-1118 (S) The declaration of "end_itr" uses the undefined class "boost::filesystem::basic_directory_iterator<boost::filesystem::basic_path<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,boost::filesystem::path_traits> >" when the class must be complete. "/mnt/releases/boost/boost_1_35_0/aix53_64-xlc9-release/include/boost/filesystem/operations.hpp", line 787.21: 1540-0700 (I) The previous message was produced while processing "boost::filesystem::detail::remove_all_aux<boost::filesystem::basic_path<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,boost::filesystem::path_traits> >(const basic_path<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,boost::filesystem::path_traits> &, file_status)". "/mnt/releases/boost/boost_1_35_0/aix53_64-xlc9-release/include/boost/filesystem/operations.hpp", line 495.28: 1540-0700 (I) The previous message was produced while processing "boost::filesystem::remove_all<boost::filesystem::basic_path<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,boost::filesystem::path_traits> >(const basic_path<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,boost::filesystem::path_traits> &)". "/mnt/releases/boost/boost_1_35_0/aix53_64-xlc9-release/include/boost/filesystem/operations.hpp", line 727.16: 1540-0700 (I) The previous message was produced while processing "boost::filesystem::remove_all(const path &)". make: 1254-004 The error code from the last command is 1. Stop. Any ideas? Same app builds just fine on aix53 xlc8 and aix61 xlc9 and xlc10. I'm stumped. Thanks

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boost::interprocess, allocators and containers of containers
by Matthew Stump 13 Jul '10

13 Jul '10

I'm attempting to create a buffered queue backed by a memory mapped file. The main data structure is a boost::interprocess::list of boost::interprocess::shared_ptr< Buffer<T> >. Buffer<T> is a struct that has two members: an interprocess_upgradable_mutex and a interprocess::deque. When I attempt to push an item into the deque contained by the struct I get a SIGSEGV in rbtree_best_fit::priv_mark_as_free_block() at line 1153 when using boost 1.43. I'm passing the allocator to the constructor of the deque as instructed in the documentation and I'm using all types which should be boost::interprocess safe. I've spent a couple hours on this one item and I'm not making any progress; I was wondering if someone could please lend me a hand. Source excerpt and backtrace: https://gist.github.com/ff7912d4582d68b825c3 Thanks, Matt Stump P.S. Other helpful criticism of my usage or advice on boost::interprocess would be greatly appreciated.

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apply std::pow to vector or matrix
by Max S. Kaznady 13 Jul '10

13 Jul '10

I followed the UBLAS extensions here: http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl?Examples_-_H… and I figured out how to extend functions like "exp" and "log" to act on a vector. But, those are functions of one argument. What I want is to be able to apply a function with one fixed argument, like std::pow, to a vector for some exponent exp, so I would like the code to look like: vector<double> v( 100 ); double exponent = 2.1; // some exponent value // ... fill v ... std::cout << apply_to_all( v, functor::my_pow<double>(exponent) ) << std::endl; std::cout << apply_to_all<functor::my_pow<double>(exponent) >( v ) << std::endl; OR std::cout << apply_to_all( v, functor::my_pow<double>() , exponent) << std::endl; How can I do this? I tried overloading apply_to_all and writing constructor code, but it didn't work because the return type of the apply function is static. P.S. I tried posting this to ublas lists, but got a message saying that my e-mail address is not registered. I guess that list is only for developers. Thanks, Max

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Memory management of boost::mutex
by Markus Henschel 13 Jul '10

13 Jul '10

Hi, we have a custom memory manager that overrides global new/delete. It is currently not thread safe. Because we require thread safety now I wanted to ad a mutex and some locks around the critical parts. Unfortunately boost::mutex allocates memory itself. So while the memory manager is created it tries to create it's mutex which causes global new to be called which calls the memory manager which is not created yet. I solved this for several data structures inside the memory manager by using custom allocators and by overriding the memory managers new operator to directly call malloc and free for its needs. But I don't see a way to customize memory management in boost mutex. Can it be achieved somehow? Thanks Markus Henschel Lead Programmer YAGER Development GmbH Pfuelstraße 5 10997 Berlin Germany www.yager.de Sitz der Gesellschaft: Berlin | Geschäftsführer: Timo Ullmann, Uwe Beneke Amtsgericht Berlin-Charlottenburg | HRB 78261 | USt-ID-Nr. DE 212404124

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Boost 1.42.0: DateTime ISO Timestamp Parsing Fix
by Peter Klotz 13 Jul '10

13 Jul '10

Boost.DateTime 1.42.0 falsely converts "20100713" into "20100713T201007.300000" using from_iso_string(). Example Code: const boost::posix_time::ptime time=boost::posix_time::from_iso_string("20100713"); std::cout << boost::posix_time::to_iso_string(time) << std::endl; Current Result: 20100713T201007.300000 The error is caused by boost::date_time::split(). The attached patch corrects split() so that an exception is thrown later in parse_delimited_time_duration(). We assume this behaviour to be better than creating a ptime that contains wrong values. Regards, Peter.

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ptr_vector documentation
by Paul Harris 12 Jul '10

12 Jul '10

Hi, Why is it that ptr_vector's documentation has everything EXCEPT the header that I need to include? http://www.boost.org/doc/libs/1_43_0/libs/ptr_container/doc/ptr_vector.html no mention of what headers are required... very frustrating, so either I have to look through all the other documentation and hope I find it, or look for the file on the harddisk, or trial-by-error... this problem seems to be common in boost documentation, is there a good reason why, or is this something that can be improved? thanks Paul

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[ProgramOptions] Hex argument values
by Robert Jones 12 Jul '10

12 Jul '10

Hi All Bit of a newbie to Boost.ProgramOptions... Is there a 'proper' way to specify that an argument has a hex value? I could take it as string and then check, but I'd prefer to let ProgramOptions do it for me. Thanks, Rob.

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[Memory] Problems when calling virtual class function
by Janez Urevc 12 Jul '10

12 Jul '10

Hello, I am doing a research about Monte Carlo Tree Search efficiency on KBNK chess ending. I use framework and algorithm implementation in C++. Since I had some memory leaks, that I couldn't manage to identify, I decided to try Boost's shared_ptr. I reorganized the whole thing to use it, but I encountered a problem, which I cannot solve. The problem occurs, when I try to call class member function, which was declared "virtual" in super class. If I try to call functions, that are not redefined, everything works as expected. Ex.: class Base{ public: int val = 0; virtual void fun(){ /* do something */} }; class Derived : public Base{ public: void fun(){ /*redefined*/} void fun1(){ /*not redefined*/} }; /* ... */ boost::shared_ptr<Base> object(new Derived); object->val = 1; //this works ok object->fun1(); //also works ok object->fun(); //does not work, I get segfault and "<symbol is not available>" error in stack trace I get the same problem if I use boost::shared_ptr<Derived> instead of boost::shared_ptr<Base>. If I change fun() in Base class to non-virtual thing works (then I cannot use polymorphism of course). I use Boost 1.4 on Ubuntu 10.04. Hope someone could help me. JAnez --- Janez Urevc Pod anteno 3a 6320 Portorož Slovenija GSM: +386 (0)40 731 632 email: janez(a)janezek.org blog: http://www.janezek.org skype: slashrsm gtalk: janez(a)janezek.org twitter: slashrsm

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Is there any Template [Meta] Programming Technique available to achieve this?
by A L 12 Jul '10

12 Jul '10

Hi, I am working on a UI system. I have created a prototype factory using the regular pattern. The abstract "product" class (each product class takes only the "name" of the product as the parameter) which is the parent of all the product classes that the proto-factory creates, contains a lonnnnnng enumeration - each product class uses some of the enumerators contained inside the enumeration. Having developed the factory, I have realized that there are various other "thing" that I can "manufacture" using the same approach. So, I want to re-use the proto-factory. For that I need to templatize the product classes and the factory class and need to "manufacture" the proto-factory itself from a proto-factory generator class (another factory, that is). The problem is, the different enumerators/constants required by each product class don't allow me genericize the design. For example, I have an Align class which uses the following enumeration: enum text_align_type { text_align_not_set = -1, text_align_left = align_left_key, text_align_center = align_center_key, text_align_right = align_right_key, text_align_justified = align_just_key }; Now the Align class takes the string "Align" as its constructor parameter and sets one of its values to text_align_not_set using the initialization list. It makes use of all of the above enumeration constants in its validation and so on. Since the proto-factory is creating the products by cloning using the copy constructors of the registered objects, I think a solution would be to pass all these enumeration constants in the constructor of each product class (besides the productName argument which is already being passed to each product class constructor). This way, I will need to create/registered these products only once in the proto-factory registry and subsequent products will then be generated/manufactured (i.e. copy-constructed) from the registered products. PROBLEM ======== Passing enumeration constants in constructors for the sole purpose of validation, etc. seems to be a bit inefficient to me. Yet I also want to re-use the design. I wonder if I could use Boost and its template/meta-programming magic to somehow pass these enumeration constants to each product class without having to pass them in product class constructors. Any ideas? -Asif

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