February 2009 - Boost-users - lists.preview.boost.org

[iterator] - does there exist an opposite of Function Output Iterator?
by Michael Fawcett 06 Feb '09

06 Feb '09

http://www.boost.org/doc/libs/1_37_0/libs/iterator/doc/function_output_iter… Shows a unary function being adapted as an OutputIterator. Does Boost have something that does the opposite, i.e. takes an OutputIterator and adapts it as a unary function object? In my own code I currently have: template <typename OutputIterator> struct output_iterator_function { explicit output_iterator_function(OutputIterator i) : iter(i) { } template <typename T> void operator()(const T &v) { *iter++ = v; } OutputIterator iter; }; template <typename OutputIterator> output_iterator_function<OutputIterator> make_output_iterator_function(OutputIterator i) { return output_iterator_function<OutputIterator>(i); } If this doesn't already exist in Boost.Iterator, it seems like it would nicely complement the already existing function_output_iterator. --Michael Fawcett

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glibc detected corrupted doubly-linked list (unit test)
by Ross Boylan 05 Feb '09

05 Feb '09

I get error shown below when I try to test my program. It appears to be coming directly out of the unit test framework, though this is after a test, and so my code could have done something. Can anyone help me determine what is going on or how to fix it? Valgrind shows the error, but it's source is mysterious. This was generated on Debian GNU/Linux etch with 64 bit Xeon and gcc. The same tests run fine on Debian testing with 32 bit AMD and OS-X on 64 bit powerpc (although I think the older version of the OS on the machine is mostly 32 bit). *** glibc detected *** corrupted double-linked list: 0x00000000005fd2a0 *** Program received signal SIGABRT, Aborted. 0x00002affd559207b in *__GI_raise () from /usr/lib/debug/libc.so.6 Current language: auto; currently c (gdb) where #0 0x00002affd559207b in *__GI_raise () from /usr/lib/debug/libc.so.6 #1 0x00002affd559384e in *__GI_abort () from /usr/lib/debug/libc.so.6 #2 0x00002affd55c85f9 in __libc_message () from /usr/lib/debug/libc.so.6 #3 0x00002affd55cd9cc in malloc_consolidate () from /usr/lib/debug/libc.so.6 #4 0x00002affd55cf789 in _int_malloc () from /usr/lib/debug/libc.so.6 #5 0x00002affd55d116d in *__GI___libc_malloc () from /usr/lib/debug/libc.so.6 #6 0x00002affd518f93d in operator new () from /usr/lib/libstdc++.so.6 #7 0x00002affd516e5d1 in std::string::_Rep::_S_create () from /usr/lib/libstdc++.so.6 #8 0x00002affd516ef8b in std::string::_Rep::_M_clone () from /usr/lib/libstdc++.so.6 #9 0x00002affd516f895 in std::string::reserve () from /usr/lib/libstdc ++.so.6 #10 0x00002affd51690a5 in std::basic_stringbuf<char, std::char_traits<char>, std::allocator<char> >::overflow () from /usr/lib/libstdc++.so.6 #11 0x00002affd516da8d in std::basic_streambuf<char, std::char_traits<char> >::xsputn () from /usr/lib/libstdc++.so.6 #12 0x00002affd5163512 in std::operator<< <std::char_traits<char> > () from /usr/lib/libstdc++.so.6 #13 0x00002affd4fbb175 in boost::unit_test::results_collector_t::test_unit_finish () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #14 0x00002affd4fb8180 in boost::unit_test::framework_impl::visit () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #15 0x00002affd4fc9f1b in boost::unit_test::traverse_test_tree () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #16 0x00002affd4fb72d8 in boost::unit_test::framework::run () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #17 0x00002affd4fc2b35 in main () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #18 0x00002affd557f4ca in __libc_start_main () from /usr/lib/debug/libc.so.6 #19 0x000000000040420a in _start () at ../sysdeps/x86_64/elf/start.S:113 -- Ross Boylan wk: (415) 514-8146 185 Berry St #5700 ross(a)biostat.ucsf.edu Dept of Epidemiology and Biostatistics fax: (415) 514-8150 University of California, San Francisco San Francisco, CA 94107-1739 hm: (415) 550-1062

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Citing Boost libraries
by Niko Vuokko 05 Feb '09

05 Feb '09

Hi, I remembered once seeing an entry on the website saying how one should cite the Boost project. Now however I can't find it when I'd need it. Thus, is 'Boost Project, http://www.boost.org' enough or is there some policy on citing? Niko Vuokko

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Any restriction on adding a boost/sandbox library to dmoz (open directory)?
by er 05 Feb '09

05 Feb '09

Hello, Are there any restrictions on adding a boost/sandbox library that I wrote under the boost license to dmoz (open directory project) to facilitate online searches?

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Re: [Boost-users] proto: analytical-only math functions
by Hicham Mouline 05 Feb '09

05 Feb '09

> ----- Original Message ----- > From: "Eric Niebler" <eric(a)boost-consulting.com> > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] proto: analytical-only math functions > Date: Thu, 05 Feb 2009 08:40:05 -0800 > > > Hicham Mouline wrote: > > Hi Eric, > > > > Thank you for the LHS grammar. I have made the changes you suggested in the > > attached files. > > > > The main header <math.h> (I'll change this name later) includes constants > > (c0 ... c100), variables(x0... x100 and x y z S r q v t), basic functions > > from <cmath> and general functions defined by the user, with dimensions 0 to > > 100. > > > > Question1: With PP, I define constants c0 to c100, as non-const because I > > let the user initialize them to a integer variables or literals or floating > > point variables or literals. > > I don't understand, but it probably doesn't matter. PP is boost.preprocessor. I forgot attached files don't appear in the mailing list. template <unsigned int subscript> struct constant_tag {}; proto::terminal< constant_tag<0> >::type c0 = {{}}; // with preprocessor, i define c0 ... c100 I don't want lib users, in a first use, to have to define constant names nor variable names themselves. > > Does the non-constness matter? They are defined in a header file included by > > users of the library. > > You'll have linker trouble if two translation units include that header. You > should define them in a .cpp file and mark them as extern in the header. Right. Could i define them const and still assign values (like arithmetic literals) to them later on? > > > Queestion3: I made dimension_of a numerical metafunction with an embedded > > value member. > > OK, that's reasonable. > > > What is the convenience > > of making metafunctions numerical? > > I don't know what you're asking. I'm just asking about a general advice re whether to make metafunctions numerical whenever possible. > > Question4: What is a quick way to test fundef_lhs_grammar does what I > > intend? > > When I want to test a grammar, I define two functions like this: > > template<typename E> > void assert_matches( E const & ) > { > BOOST_MPL_ASSERT((proto::matches<E, fundef_lhs_grammar>)); > } > > template<typename E> > void assert_not_matches( E const & ) > { > BOOST_MPL_ASSERT_NOT((proto::matches<E, fundef_lhs_grammar>)); > } > > Then in main(), I can create expressions and pass them to one of these > functions. Either it matches or it doesn't, and I can find out at compile time. > Great, will do. I'll leave the grammar of the RHS of = operator till later. My next question is about my constants. I want to allow this example of syntax: c35 = any expression of integral or floating point literals, of c++ runtime variables of integral or fp type (no bool no enums) of _other_ constants Later, a constant will be either undefined, or defined. if undefined, evaluations of expressions with that constant will keep that constant in, otherwise, the constant will be replaced by its value How do I write the grammar that allows any expression, but just with those 4 possibilies (c35)? regards,

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boost::lambda: how to create indirect functor
by ＠ 05 Feb '09

05 Feb '09

prerequisites: struct C { void func(int i) {} }; void indirect(boost::function<void(C*)> f) { static C c; f(&c); } I need a functor that takes int and calls "indirect" passing there &C::func bound with that int. I imagine a solution like: boost::function<void(int)> result_functor = bind(indirect, bind(&C::func, protect(_1), _1)); receiving compilation error: "could not deduce argument" deep inside lambda library thanks -- View this message in context: http://www.nabble.com/boost%3A%3Alambda%3A-how-to-create-indirect-functor-t… Sent from the Boost - Users mailing list archive at Nabble.com.

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Re: [Boost-users] [boost] [SVG Plot] What happened to this library?
by Marc Viala 05 Feb '09

05 Feb '09

Hello, I have just checked out the latest release of SVG Plot library from https://svn.boost.org/svn/boost/sandbox/SOC/2007/visualization/ and tried to compile one source example w/ VC++ 7.1 against Boost 1.37.0 but the compilation failed. The file source is "1d_simple.cpp" from the of SVG Plot example directory. The compilation of the source file fails with the following error: 'svg_color_constant' unknown identifier in file svg_color.hpp @ line37 Did I miss something? Best regards, Marc Viala > -----Message d'origine----- > De : boost-bounces(a)lists.boost.org > [mailto:boost-bounces@lists.boost.org] > De la part de Paul A. Bristow > Envoyé : jeudi 5 février 2009 10:35 > À : boost(a)lists.boost.org > Objet : Re: [boost] [SVG Plot] What happened to this library? > > > -----Original Message----- > > From: boost-bounces(a)lists.boost.org [mailto:boost- > bounces(a)lists.boost.org] > On > > Behalf Of Joel > > Sent: 04 February 2009 23:45 > > To: boost(a)lists.boost.org > > Subject: [boost] [SVG Plot] What happened to this library? > > > > Paul A. Bristow <pbristow <at> hetp.u-net.com> writes: > > > 3 I am close to updating the documentation (and enhanced code) > > > for the > GSoC > > > 2007 SVG plot project by Jake Voytko - including Doxygenation and > > > John Maddock's auto indexing. The code is in a useful (but > > > unpolished) state > and > > > I am confident it will allow neat graphs to display data like > time_series > > > with minimal programming effort. The SVG files produced are tiny, but > high > > > quality, and can be viewed with quality browsers. > > > Is there a URL for this current version of the code? A quick look > > on > google > > only found me Jake's site which is from August 2007: > > > > http://www.jakevoytko.com/code.php > > That is way out of date. > > There is the latest version on SVN > > https://svn.boost.org/svn/boost/sandbox/SOC/2007/visualization/ > > but I am still actively working on it (especially the docs) so use at > your own risk (peril even!). > > Feedback welcome of course. > > > Also, will there be boost graph support? > > Not unless you provide it ;-) > > Paul > > --- > Paul A. Bristow > Prizet Farmhouse > Kendal, UK LA8 8AB > +44 1539 561830, mobile +44 7714330204 > pbristow(a)hetp.u-net.com > > > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost

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ASIO sockets and stream buffers
by Jeff Diewald 05 Feb '09

05 Feb '09

I'm having trouble with trying to connect my TCP sockets up to a stream buffer, and need some help. I've already opened my sending socket, or accepted a connection to get a new receiving socket, and I want to send messages back and forth. What I'd like to write is something like: void sendMessage(boost::asio::ip::tcp::socket* s) { ?? some stream type ?? str(s); str << ... write stuff ... << flush(); str >> ... read stuff ...; } I can't seem to find the right stream type that takes my existing socket. Does such a creature exist in the ASIO library? Help! Thanks in advance, Jeff Diewald JEOL USA

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Re: [Boost-users] boost and std collisons in c++0x
by Daniel Lidström 05 Feb '09

05 Feb '09

Hello, here is how I have solved this problem where I work: Create a header for each class that you want to use, that exists in both boost and std::tr1. For example, here's our local shared_ptr.h: #if !defined(SHARED_PTR_H__20080527T1436) #define SHARED_PTR_H__20080527T1436 #if defined(_MSC_VER) && _MSC_VER>=1500 && defined(_HAS_TR1) // Visual Studio 2008 TR1 version #include <memory> namespace GFLUtils = std::tr1; #else // Boost version #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> namespace GFLUtils = boost; #endif #endif If you also have to rely on VC6 (as we do) then you can't selectively import parts from a namespace (using boost::shared_ptr doesn't work). But if you only use more modern compiler, you can do this: #if !defined(SHARED_PTR_H__20080527T1436) #define SHARED_PTR_H__20080527T1436 #if defined(_MSC_VER) && _MSC_VER>=1500 && defined(_HAS_TR1) // Visual Studio 2008 TR1 version #include <memory> namespace GFLUtils { using std::tr1::shared_ptr; using std::tr1::enable_shared_from_this; } #else // Boost version #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> namespace GFLUtils { using boost::shared_ptr; using boost::enable_shared_from_this; } #endif #endif Hope this helps! Regards, Daniel Lidström Stockholm, Sweden _____ From: Ein Held [mailto:held_ein@yahoo.de] Sent: Wednesday, February 04, 2009 1:23 PM To: boost-users(a)lists.boost.org Subject: [Boost-users] boost and std collisons in c++0x Hello I would like to know more about boost's general attitude towards c++0x and the collisions of boost with std. As of now, we move both, ::boost- and ::std-namesspace in the global namespace via using xxx. This is exactly what we want - boost and the stl are both such fundamental libraries that using an explicit namespace specifier everytime we want to use content of these namespaces is not accaptable. This would just blow the code and make it unreadable. Once we move up to c++0x, we will not be able to keep this way of coding up. ::std::tr1 is merged into ::std and so the former tr1 classes will collide with the boost ones if explicit namespace identifiers are missing. I would like to stress the fact that code, perfectly fine to the boost documentation, will fail to compiler most likely. #include <iostream> //This one might include <array> using namespace std; #include <boost/array.hpp> using namespace boost; array<int,1> blub; //fail Is there anything planned to prevent this happen? Thank you

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[Accumulator] Build error in using BOOST::accumulator on WXP VC8
by dhruva 05 Feb '09

05 Feb '09

Hello, I am using BOOST::accumulator from 1.37. I get the following warning in the build on WXP using VC8 (MSVC 2005). I am exploring to find out where the problem could be, posting to find is someone has experienced this problem. Since our build treats warnings as errors, I am stuck. ...include\boost/fusion/container/vector/detail/deref_impl.hpp(46) : warning C4003: not enough actual parameters for macro 'index' -dhruva -- Contents reflect my personal views only! Add more friends to your messenger and enjoy! Go to http://messenger.yahoo.com/invite/

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