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boostcon slides online
by Ares Lagae 08 Jun '07

08 Jun '07

One of the previous posts in this list made me wondering. Wouldn't it be nice to have the slides from the boostcon talks online? Best regards, -- Ares Lagae Computer Graphics Research Group, Katholieke Universiteit Leuven http://www.cs.kuleuven.be/~ares/

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[integer] Request: long long (64 bits) support for int_t and uint_t
by Niels Dekker - mail address until 2007-11-30 08 Jun '07

08 Jun '07

I would like to have "long long" and "unsigned long long" supported by boost::int_t and boost::uint_t. E.g., on Win32, VC++, I would expect int_t<64>::least to get me a long long. Are there plans to add this kind of support? Otherwise, should I submit my request as a ticket to svn.boost.org/trac/boost ? It looks like "long long" support can be added quite easily, as I already did so on my local copy of boost/integer.hpp. -- Niels Dekker http://www.xs4all.nl/~nd/dekkerware Scientific programmer at LKEB, Leiden University Medical Center

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boost::bind as composite
by Boris 08 Jun '07

08 Jun '07

Hi, I have two predicates f1 and f2 and I want to construct the predicate f4 = f1 && f2 using boost::bind. Unfortunately I observe a strange behaviour of boost::bind I can not explain. struct Test { int a; int b; }; Test t = { 1, 2 }; typedef boost::function< bool (Test const&) > Fn; Fn f1 = bind( &Test::a, _1 ) == 1; assert (f1( t )); // Ok Fn f2 = bind( &Test::b, _1 ) == 3; assert (!f2( t )); // ok Fn f3 = bind( std::logical_and< bool >(), bind( &Test::a, _1 ) == 1, bind( &Test::b, _1 ) == 3 ); assert (!f3( t )); // Ok Fn f4 = bind( std::logical_and< bool >(), f1, f2 ); assert (!f4( t )); // assertion failed Why does the predicate f4 behave different from f3? Thanks, Boris

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[parameter] A few usage questions
by John Maddock 08 Jun '07

08 Jun '07

I have a few usage questions for the Boost.Parameter library: 1) If I want to have a function called "policy" that's declared using BOOST_PARAMETER_FUNCTION can I access the types of the arguments both from within the functions body and for the functions return type: BOOST_PARAMETER_FUNCTION( (return-type-computed-from-arguments), policy, tag, // 3. namespace of tag types (optional // optional parameters, with defaults (domain_error, *, throw_on_error) ) (deduced (optional (precision, *, boost::mpl::int_<53>()) ) ) ) { // what type are the arguments? } I realise I can do this with an argument pack, but then either my users will have to call the function with an extra set of parenthesis, or I will have to write a bunch of forwarding functions myself - which itself generates a "what the is the return type" problem. >From within the body of the BOOST_PARAMETER_FUNCTION generated function it appears that I can use the name "Args" to refer to the type of the argument pack, and maybe in the return type as well? But this isn't documented, so can I rely on it? 2) All the arguments I want to pass are actually going to end up being used in meta-programs: for symbolic values, I can make each one a unique enum type, and use the type of the argument (even though it's actually passed as a value) to generate my metacode. But I have one optional argument where I require the value to be an arbitrary compile time constant, the only interface I can come up with at present is something like: policy(_digits10 = mpl::int_<10>()); But I'd really like to be able to write: policy(_digits10 = 12); and have the "12" converted to mpl::int_<12> "by magic", but I can't think of any magic that could be applied here... anyone any ideas? Thanks, John.

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[boost::variant] does 'incomplete<T>' still exist?
by jono 08 Jun '07

08 Jun '07

hi. i read a tutorial at http://electra.lbl.gov/stuff/variant/doc/tutorial.html which says a boost::variant type can be declared with an incomplete type in its typelist by using incomplete<T>. i'm using boost 1.33.1 & i can't find incomplete<T> anywhere. does it still exist? the tutorial is dated '14 February 2003'. can variants use incomplete types? i want to have a variant represent a type which has a variant member. can i do that? i'm working on a kind of envelope/letter idiom for dispatching operations on values. cheers jono

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Re: [Boost-users] port of GameDev SDL lib in Boost?
by Christian Henning 08 Jun '07

08 Jun '07

Hi there, I think there is something wrong with the timer. Whenever I run the code ( see below ) it slows down for whatever reason. Is that a known problem? When I look at the output the frequency is certainly not 10 times a second. #include <windows.h> #include <iostream> #include <sdl.h> using namespace std; Uint32 time_elapsed( Uint32 interval, void* param ) { cout << interval << endl; return ++interval; } int main( int argc, char* argv[] ) { SDL_Init( SDL_INIT_VIDEO | SDL_INIT_TIMER ); SDL_TimerID id = SDL_AddTimer( 100, &time_elapsed, NULL ); SDL_Event event; while( SDL_PollEvent( &event ) >= 0 ) { ::Sleep( 100 ); } return 0; }

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[signal] Invoking connect with same argument a second time allowed?
by Boris 08 Jun '07

08 Jun '07

Is it allowed to call connect() with the same argument (slot) a second time (without disconnecting in between)? I've been checking the documentation at http://www.boost.org/doc/html/boost/signalN.html#id1033842-bb but couldn't find any answer. I assume it is allowed (it doesn't throw any exception et al.) but don't want to build a software based on assumptions really. ;-) Boris

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wave: preprocessing Visual C++ 2005 stl
by Ludovic Aubert 07 Jun '07

07 Jun '07

Hello boost wave users, I have written a sample program which uses boost wave and I am trying to run it on its own source code. The environnement (especially the stl) is Microsoft Visual C++ 2005. Since typically an include file like "vector" will be preprocessed many times (once for every compilation unit), I am saving all the preprocessed tokens in a map<string, map<tuple<int,int>,string> > token, so that token[path][make_tuple(line,col)] = value. Then for each path I am using a forward iterator to spit out all the values into a buffer. The major trouble I have is with the macros #define STD_BEGIN namespace std { #define STD_END } defined in the file "yvals.h" Somehow, STD_BEGIN and STD_END are replaced by blanks and I get "namespace std{}" at the end of the files instead. Looks like the line and col for these items are wrong ... I would like to know if someone has already successfully preprocessed the stl delivered with Visual C++ 2005. Thank you in advance for your reply Ludovic Aubert

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Filesystem Exception
by Surya Kiran Gullapalli 07 Jun '07

07 Jun '07

Hello all, I'm creating a directory using boost::filesystem::create_directory function. When i looked at the documentation, It said, Throws: basic_filesystem_error<Path> if Effects fails for any reason other than because the directory already exists. Now when i catch the exception like this try { boost::filesystem::create_directory (path) } catch (boost::filesystem::basic_filesystem_error <boost::filesystem::path>& e) { cout << e.what() << endl ; } e.what() returns the string boost::filesystem::create_directory. What i expect is why the create_directory failed. How can i get the string describing the problem. Thanks in advance, Surya

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Re: [Boost-users] port of GameDev SDL lib in Boost?
by Christian Henning 07 Jun '07

07 Jun '07

My current version is more or less ready to use. you can check it here: http://gil-contributions.googlecode.com/svn/trunk/gil_2/boost/gil/extension… Let me know what you think. I'm not so sure if you can put your callback timer under the boost license. Maybe somebody else knows the answer. Christian On 6/6/07, fanzhe cui <fanzhe.cui(a)goldiom.com> wrote: > Christian, > > Boost is very widely accepted and utilized by game developers, and on the > web GameDev.net there are many many articles about various boost sub lib. > But I haven't seen many discussions about SDL lib on this boost mail list > from boost users/developers. SDL is very convenient cross-platform C++ > development platform that can be used not only game developers but also by > other developers. It has easy-to-use classes of multithreads, mutex, event > queues, timer callbacks, semaphores, key board input handling, audio, video, > to name a few. Most of these functionalities are available from Boost lib. > But I haven't seen good timer callback available from Boost lib (anybody can > correct me if I am not so informed of Boost timer). > > I tried to extract the timer functions (classes) from the SDL lib into an > individual timer lib, and the work is still in progress. I am not sure other > users in the list are interested in knowing about porting SDL timer to > Boost. So if you can tell me your email of this email list, I can send you > the project file. > > What exactly I did was that I included the relevant source files from SDL > package, and compile it with testing program. I was able to get the exe file > but the project also generated a library file in addition to the exe file. I > am confused by the fact that the project generating TimerTest.lib, that I > don't want t. Rather, I wanted to link them with TimerTest not intended to. > I checked the project configuration file, and there is no setting that will > generate a library file. I think it might be set in the program source code, > but I did not find it. > > I am interested in your idea of implement SDL wrapper in boost lib. Thank > you! > > Best regards, > Fanzhe Cui > +++++++++++++++++++++++++++ > Goldiom Systems LLC > - Information and Communication Technology Provider > Email: fanzhe.cui(a)goldiom.com > Tel: 973-210-4254 > www.goldiom.com > > > -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Christian Henning > Sent: Wednesday, June 06, 2007 10:06 AM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] port of GameDev SDL lib in Boost? > > Fanzhe, I have been working on a sdl wrapper for boost::gil. It lets > you draw on a canvas and react to event such as a timer event. I was > thinking of outsourcing this portion so people can use just that. The > good thing is the sdl is supporting almost the same platforms as boost > does. The bad thing probably is the license sdl is using, LGPL. > > If you want I can give you a pointer for the code. > > Christian > > On 6/6/07, fanzhe cui <fanzhe.cui(a)goldiom.com> wrote: > > Yes, I was referring to that library and more info could be found from the > > web: http://www.libsdl.org/. > > The problem with the boost timer that you mentioned is that it provides > the > > time elapsed, but not the interface like provided by SDL lib. Particularly > > the kind of timer callback function that is available in SDL lib is not > > available in Boost lit. > > > > Best regards, > > Fanzhe Cui > > > > ++++++++++++++++++++++ > > Goldiom Systems LLC > > - Information and Communication Technology Provider > > Email: fanzhe.cui(a)goldiom.com > > Tel: 973-210-4254 > > www.goldiom.com > > > > -----Original Message----- > > From: boost-users-bounces(a)lists.boost.org > > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Tarjei Knapstad > > Sent: Wednesday, June 06, 2007 4:02 AM > > To: boost-users(a)lists.boost.org > > Subject: Re: [Boost-users] port of GameDev SDL lib in Boost? > > > > On 6/6/07, fanzhe cui <fanzhe.cui(a)goldiom.com> wrote: > > > I have been using both Boost lib and GameDev SDL lib in same projects. > > Both > > > of the lib have very good platform independency. But they have some > > > functionalities overlapping each other and I would like to use only one > of > > > them. The timer lib in GameDev SDL is very easy to use and I hope such > lib > > > or functionally similar one exists in Boost lib. I had a look at boost > > > archive on previous discussion on implementing Boost timers and feel > that > > > there is still no good implementation of timer in Boost lib (correct me > if > > I > > > am wrong). Anybody in this email list had a look at GameDev timer and > have > > > considered implementing such a lib in Boost? > > > > > > > Are you referring to the Simple Direct Medialayer? > > > > http://lazyfoo.net/SDL_tutorials/lesson12/index.php > > > > What's wrong with/missing in boost::timer ? > > > > http://boost.org/libs/timer/index.html > > > > -- > > Tarjei > > _______________________________________________ > > Boost-users mailing list > > Boost-users(a)lists.boost.org > > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > > > > > > _______________________________________________ > > Boost-users mailing list > > Boost-users(a)lists.boost.org > > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

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