January 2006 - Boost-users - lists.boost.org

Re: [Boost-users] Getting started with Boost: what did you need to know?
by Toby Smith 13 Feb '06

13 Feb '06

> I'm giving a talk about getting started with Boost > (https://www.cmpevents.com/SDw6/a.asp?option=G&V=3&id=271893) and I > thought it would be a good idea to solicit input from those who have > recently gone through the process. What do you wish someone had > explained to you? With what did you need hand-holding? Based on this > feedback I expect to make some improvements to the Boost website, > also. Any information you can give me will be much appreciated. Personally, my biggest problem with getting started with boost was realizing that I should get started in the first place. I'd had friends & coworkers mention boost, but to the new visitor, the website (as clean and readable as it is) doesn't do a good sell job for the product. It starts off well, saying that there's some sort of libraries to be had in here somewhere. But the first eight links the reader encounters have nothing to do with explaining why it is you might want to use these libraries. The ninth link, "Background information page," finally gives us a teaser, claiming our productivity will increase, but we still don't know why. Only the intrepid explorer who delves into the tiny "Documentation" link on the main page will be rewarded with a catalog of functionality. In short, I think the main page, the page that should be grabbing the casual surfer's attention, should at least highlight some of the functionality the consumer can expect from boost (cross-platform serialization, anyone? How about containers done right, or a well- designed thread package?), instead of devoting real estate and reader attention to links to random unix distros. Cheers, tob

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Unable to figure out how to get zlib support in iostreams on windows
by cheesy4poofs 10 Feb '06

10 Feb '06

Hi, I've posted this on the boost build forums, but never got a response, so I'm hoping someone in this group can help me. I've spent several days banging my head with iostream zlib support on windows. For the life of me, I cannot figure out how to get this to compile. This is on a windows XP machine with Microsoft VS 2003. I've installed the zlib source at C:\dev\zlib and set the appropriate command line arguments (I believe anyway) to point to it. However, it continues to give me an error of "unknown dependent target <@boost!libs!iostreams!build>libboost_zlib.lib" If I remove the zlib command line arguments, the boost library builds fine. Can anyone please explain what I'm doing wrong? I'm sure it is something simple, but I cannot figure it out. I looked at the jam file regarding this and it seems to indicate that it will compile zlib automatically. But apparently that isn't happening. The complete output from the command window follows. Thanks in advance for any help! Scott bjam "-sTOOLS=vc-7_1" "-sNO_COMPRESSION=0" "-sNO_ZLIB=0" "-sZLIB_SOURCE=C:\Dev\zlib" "-sZLIB_INCLUDE=C:\Dev\zlib" stage ****************************************************** Building Boost.Iostreams with bzip2 support disabled. To enable bzip2, consult the Boost.Iostreams documentation ****************************************************** --------------------------------------------------------------------- *** If you don't need Boost.Python, you can ignore this section *** *** pass --without-python to suppress this message in the future *** skipping Boost.Python library build due to missing or incorrect configuration couldn't find Python.h in "c:/Python24/include" You can configure the location of your python installation by setting: PYTHON_VERSION - The 2-part python Major.Minor version number (e.g. "2.2", NOT "2.2.1") - currently "2.4" PYTHON_ROOT - automatically configured from PYTHON_VERSION if not otherwise set ; currently "c:/Python24" The following are automatically configured from PYTHON_ROOT if not otherwise set: PYTHON_LIB_PATH - path to Python library object; currently "c:/Python24/libs" --------------------------------------------------------------------- Building Boost.Regex with the optional Unicode/ICU support disabled. Please refer to the Boost.Regex documentation for more information (and if you don't know what ICU is then you probably don't need it). unknown dependent target <@boost!libs!iostreams!build>libboost_zlib.lib

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A problem with '^' and '$' in boost regex
by Alan Huang 09 Feb '06

09 Feb '06

Hi, In boost document I saw that the '^' matches all the blank chars in the begin of line and the '$' matches all the blank chars in the end of line. Just like regex( "^abc$" ) can't match the string " abc ". What's wrong? -- Yours Sincerely, Alan Huang

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Getting started with Boost: what did you need to know?
by David Abrahams 07 Feb '06

07 Feb '06

I'm giving a talk about getting started with Boost (https://www.cmpevents.com/SDw6/a.asp?option=G&V=3&id=271893) and I thought it would be a good idea to solicit input from those who have recently gone through the process. What do you wish someone had explained to you? With what did you need hand-holding? Based on this feedback I expect to make some improvements to the Boost website, also. Any information you can give me will be much appreciated. Thanks, -- Dave Abrahams Boost Consulting www.boost-consulting.com

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[boost-users] [parameter] Error using positional arguments
by Cromwell Enage 06 Feb '06

06 Feb '06

In one of my projects the header files contain code like the following: #ifndef BOOST_PARAMETER_RANDOM_EXAMPLE_HPP #define BOOST_PARAMETER_RANDOM_EXAMPLE_HPP #include <boost/type_traits/remove_const.hpp> #include <boost/random/uniform_int.hpp> #include <boost/random/variate_generator.hpp> #include <boost/parameter.hpp> namespace example { BOOST_PARAMETER_KEYWORD(tag, rng_engine) BOOST_PARAMETER_KEYWORD(tag, min) BOOST_PARAMETER_KEYWORD(tag, max) BOOST_PARAMETER_KEYWORD(tag, factor) BOOST_PARAMETER_KEYWORD(tag, addend) struct foo_parameters : boost::parameter::parameters< boost::parameter::required<tag::rng_engine> , boost::parameter::required<tag::min> , boost::parameter::required<tag::max> , boost::parameter::optional<tag::factor> , boost::parameter::optional<tag::addend> > { }; BOOST_PARAMETER_FUN(unsigned int, foo, 3, 5, foo_parameters) { typedef typename boost::remove_const< typename boost::parameter::binding< Params , tag::rng_engine >::type >::type RNGEngine; typedef boost::uniform_int<unsigned int> RNGDist; typedef boost::variate_generator<RNGEngine, RNGDist> RNG; RNGEngine rng_engine = p[example::rng_engine]; RNG rng(rng_engine, RNGDist(p[min], p[max])); return rng() * p[factor | 10] + p[addend | 5]; } } // namespace test #endif // BOOST_PARAMETER_RANDOM_EXAMPLE_HPP The following snippet would then exemplify typical user code: #include <iostream> #include <boost/ref.hpp> #include <boost/random/mersenne_twister.hpp> #include "boost_parameter_random_example.hpp" int main() { boost::mt19937 rng; std::cout << "Named: " << example::foo( example::rng_engine = rng , example::min = 12 , example::max = 24 ) << std::endl; // Ok std::cout << "Unnamed: "; std::cout << example::foo(rng, 12, 24); // error std::cout << std::endl; return 0; } MinGW reports: 'static const T& boost::random::detail::ptr_helper<T&>::ref(const T&) [with T = const boost::mt19937]' and 'static T& boost::random::detail::ptr_helper<T&>::ref(T&) [with T = const boost::mt19937]' cannot be overloaded When I wrap boost::ref around rng, the program runs fine. I'm curious as to why I get this error only when specifying positional arguments. Have I run afoul of something fundamental, such as the forwarding problem? Cromwell D. Enage __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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[parameters] Runtime enumeration of parameter list
by Neil Hunt 05 Feb '06

05 Feb '06

>From a post about using strings as an indexing mechanism: "David Abrahams" <dave(a)boost-consulting.com> wrote in message news:ubqzqz3sw.fsf@boost-consulting.com... <snip> >> Since all are known at compile time I'm sure it must be easy to do >> this. I'm pretty sure when someone shows me the obvious solution I >> will be very embarrassed, but until then I can do this with a >> std::map at runtime, but not at compile time. > I'm pretty sure the parameter library is a good -- if not perfect -- > match for your problem. Since I've pointed at it twice now, if you're > not embarrassed yet, I'll stop pushing ;-) I too am quite interested in this process of compile time indexing. Let me think out loud (visibly?). Question at the bottom. I have often used this pattern of access for a vector of a known size (contrived example): enum TabIndices { PERSON_TAB, ADDRESS_TAB, EMPLOYER_TAB, TAB_COUNT }; Window windows[TAB_COUNT]; ... display_window( TabIndices tab_index ) { windows[tab_index].display(); for( int i = 0; i < (int)TAB_COUNT; ++i ) { if( i != (int)tab_index ) windows[i].hide(); } } ... display_window( PERSON_TAB ); Let me have go at converting this to use the parameter keyword system for indexing by using an ArgumentPack. BOOST_PARAMETER_KEYWORD(tag, PERSON_WINDOW) BOOST_PARAMETER_KEYWORD(tag, ADDRESS_WINDOW) BOOST_PARAMETER_KEYWORD(tag, EMPLOYER_WINDOW)XXXX windows( ( PERSON_WINDOW = Window(), ADDRESS_WINDOW = Window(), EMPLOYER_WINDOW = Window() ) ); ... template<class keyword> display_window( keyword tab_index) { windows[tab_index].display(); for( YYYY ) { if( *iterator != tab_index ) windows[iterator].hide(); } } ... display_window( PERSON_TAB ); My two immediate problems are how to declare the type of the ArgumentPack that would actually hold the window objects. (XXXX) And secondly, how to iterate over the windows at runtime. (YYYY). I guess the main thrust of the question is "Does the parameters library support runtime enumeration?" or should I be looking at MPL? Neil

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[serialization] suggestion for the extension of the functionality
by Seweryn Habdank-Wojewódzki 02 Feb '06

02 Feb '06

Hello I would like to ask for consideration of some new functionality for boost::serialization. If I have a stream and I do not want to close the stream at the end of serialization I have to make easy, but nasty trick using stringstream as a buffer between my stream and serialized stream. More concrete example. I'am using easy library for sockets. Connection is represented as stream and after connection I do not want to close it. So when I try to use serialization though the socket, serialisation is hanging - it is waiting for the end of the stream, but there is no end of stream because it is socket. It will be useful just to add to library one fuction for manual sending data - "simulation" of the end of stream. To avoid or closing socket either using stringstreams buffers. Below is example code for this problem - this code is using buffers, but IMHO better will be that inside library will be functionality for such a situation. Best regards, Seweryn Habdank-Wojewódzki. Ps. Full code I can send if will be needed. void do_server() { string message("Hello Socket!\nHelloWorld!"); // create class instance const gps_position g(35, 59, 24.567f); try { TCPSocketWrapper sockserver; // listen on some port sockserver.listen(IPportnumber); cout << "server is ready" << endl; // accept connection from client TCPSocketWrapper sock(sockserver.accept()); cout << "accepted connection from: " << sock.address() << endl; // make the stream around the socket wrapper TCPStream stream(sock); bool oncemore = true; int command; while (oncemore) { // read the command stream >> command; switch (command) { case 1: { cout << "command 1" <<endl; // ------------------------------------------------ // buffer // ------------------------------------------------ std::ostringstream s; { boost::archive::text_oarchive oa(s); // write class instance to archive oa << g; } //------------------------------------------------------------------ // buffer //------------------------------------------------------------------ stream << s.str() << endl; } break; default: cout << "END command" << endl; oncemore = false; break; } } } catch (const SocketRunTimeException &e) { cout << "socket exception: " << e.what() << endl; } } void do_client() { string message; // ... some time later restore the class instance to its orginal state gps_position newg; try { TCPClientStream stream(IPserveraddress, IPportnumber); bool oncemore = true; int command; while (oncemore) { cout << "1. request for a serialized object" << endl; cout << "other - end" << endl; cin >> command; stream << command << endl; switch (command) { case 1: { // ------------------------------------------------ // buffer // ------------------------------------------------ std::string line; std::getline(stream, line); istringstream s(line); // ------------------------------------------------ // buffer will be filled // ------------------------------------------------ { boost::archive::text_iarchive ia(s); ia >> newg; } cout << "received: " << newg << endl; } break; default: oncemore = false; break; } } } catch (const SocketRunTimeException &e) { cout << "socket exception: " << e.what() << endl; } } -- |\/\/| Seweryn Habdank-Wojewódzki `\/\/

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[date_time] Constructing a ptime with __int64
by Christian Henning 01 Feb '06

01 Feb '06

Hi there, is it possible to construct a ptime with an __int64. The internal representation is of the same type. I couldn't find anything on this issue. Thanks in advance, Christian

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Compiling boost with vacpp 8.0 as 64bit on AIX5.3ml3 of power5
by Kamil Marcinkowski 01 Feb '06

01 Feb '06

Hello, I need to compile boost as a 64 bit program using vacpp 8.0 compiler, on AIX 5.3ml3, power5, p5-550 and p5-595. I can compile boost with vacpp in 32bit mode fine, but all my attempts at compiling it 64 bit have not resulted with any success so far. The vacpp toolset does not offer any options and does not allow for any options or configuration variables. I do not understand the syntax of the vacpp-tools.jam file or (bjam in general) and cannot edit the file with any success. I just need the following flags passed to the compiler: <cxxflags> -q64 <linkflags> -q64 <arflags> -q64 Thanks, Kamil Kamil Marcinkowski Westgrid System Administrator kamil(a)ualberta.ca University of Alberta site Tel.780 492-0354 Research Computing Support Fax.780 492-1729 Academic ICT (formerly CNS) Edmonton, Alberta, CANADA University of Alberta "This communication is intended for the use of the recipient to which it is addressed, and may contain confidential, personal, and/or privileged information. Please contact us immediately if you are not the intended recipient of this communication. If you are not the intended recipient of this communication, do not copy, distribute, or take action on it. Any communication received in error, or subsequent reply, should be deleted or destroyed."

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trying to install Boost 1.33.1 on Solaris 5.9 + SunStudio 11
by Xavier.Abulker＠fimat.com 01 Feb '06

01 Feb '06

Hello, I'm trying to install Boost 1.33.1 on a Sun Solaris 5.9 Sunpro 11 and after the command: bjam "-sTOOLS=sunpro" install I receive the error message: >> Assertion: (../lnk/init.cc, line 1032) while processing /ftx/opt/SUNWspro/prod/include/CC/Cstd/rw/messages.cc at line 0. >> Assertion: (../lnk/init.cc, line 1032) while processing /ftx/opt/SUNWspro/prod/include/CC/Cstd/rw/messages.cc at line 0. Do you know how I can solve this problem? It looks like Sun has released a patch to solve the error "Assertion: (../lnk/init.cc, line 1032)" but I can't find it for solaris 5.9 + Studio 11 Regards Xavier ************************************************************************* Ce message et toutes les pieces jointes (ci-apres le "message") sont confidentiels et etablis a l'intention exclusive de ses destinataires. Toute utilisation ou diffusion non autorisee est interdite. Tout message electronique est susceptible d'alteration. La FIMAT et ses filiales declinent toute responsabilite au titre de ce message s'il a ete altere, deforme ou falsifie. ******** This message and any attachments (the "message") are confidential and intended solely for the addressees. Any unauthorised use or dissemination is prohibited. E-mails are susceptible to alteration. Neither FIMAT nor any of its subsidiaries or affiliates shall be liable for the message if altered, changed or falsified.

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