February 2007 - Boost-users - lists.preview.boost.org

[multi_array] operator= requires resize - why?
by Markus Werle 04 Jun '12

04 Jun '12

Hi! IMHO the behaviour of operator= for multi_array is a little bit broken. A lot of preconditions required: template <typename ConstMultiArray> multi_array_ref& operator=(const ConstMultiArray& other) { [...] // make sure the dimensions agree assert(other.num_dimensions() == this->num_dimensions()); assert(std::equal(other.shape(),other.shape()+this->num_dimensions(), this->shape())); Besides the fact that I get mad about … [View More]

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Design for boost::serialization of STL iterators.
by Carlo Wood 23 May '09

23 May '09

On Sat, Mar 11, 2006 at 11:45:36PM +0200, Peter Dimov wrote: > Carlo Wood wrote: > > > 1) WHY does boost::serialization not support serialization > > of iterators? > > It's very hard, if not impossible, in general. It is either impossible or possible. When it is possible, it can't be hard :p I think that at the moment of serialization, the actual container needs to be known. So, only concentrating on the syntax of the code that serializes an iterator, the following … [View More]cannot work: ar & iter; However, the container will be known at that point (or at least, we might as well assume that). Therefore, I could imagine a syntax like: ar & foobar(container, iter); where 'foobar' is some template function (that will be part of boost::serialization in the future). Lets start with the last one (have to start somewhere). In order to deserialize the iterator (and taken into account that we already have the container) -- which makes me think that it might be better to pass a functor to operator& above. In other words, (at least for writing), use: template<class Container> struct Foobar { Foobar(Container const&, typename Container::const_iterator& iter) : M_container(container), M_iter(iter); private: Container const& M_container; Container::const_iterator& M_iter; }; and then assign to M_iter, whatever we find in M_container. > If you have access to the container to which the iterator i refers: > > a) if the container is a map, you can serialize i->first, then on > deserialization look up the key in the map using .find(); > > b) if the container is a sequence, and it has the same contents on > deserialization as it does on serialization, you can serialize the index of > the element - distance( c.begin(), i ). I don't think that it is a requirement that the whole container has to be read: either it's a map or set, in which case later insertions will not invalidate the container, or it is a vector, in which case we use an index, from which we can construct the end iterators before the whole container is reconstructed. Therefore, the following syntax can work imho: ar & FooBar(container, iter); Would you agree? There are a zillion questions and implementation details open - but I'd like to get anyones feedback about this type of interface for iterators before continuing. Current questions: What is a good name for Foobar? Am I right when I think that Foobar needs to be declared in boost::serialization? Now the hard part (for me) is that part that involves the internals of the boost library. At the moment one tries to serialize an iterator, it is possible (though not necessarily) that the object that the iterator points to is already serialized. In the case that we are dealing with an associative container (map or set etc), we don't want to store the contents of the object (or key part, in the case of a map) again: I'd like to just store that once, and store a reference in the archive at the other place. How can I make the library store an object only the first time and the store a reference the second time? This would be for an object of arbitrary type thus. I think that it is only feasible to do this when it's actually the same object (same memory address), which is the case; but while storing the object element of the container, the address of it isn't stored as well, is it? Is there a way to make: std::set<SomeData> s; [...] ar << s; Store the address of s (&s) along with the contents of s? And would that then automatically cause the library to not store that same object again when I do: std::set<SomeData>::iterator iter = s.find(...); [...] ar << *iter; Because then, &*iter would again be the same memory address as what was stored before. -- Carlo Wood <carlo(a)alinoe.com> [View Less]

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[BGL] citing the Boost Graph Library
by Alejandro Marcos Aragón 06 May '09

06 May '09

Can anyone point me how to cite the Boost Graph Library in a paper? Is there any information in the boost website? Thank you all, Alejandro Aragón

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Boost Graph Library and Boehm Garbage Collector
by FBSL 08 Sep '08

08 Sep '08

Hello I am having trouble to garbage-collect adjacency_list<>. I have instanciated it with correctly garbage-collected vectors and lists (I have copied vecS and listS definitions, and added Boehm GC's default allocator so that they are garbage-collected). In my application I need to dynamically allocate many graphs, but it does not work, there is a (big) memory leak. Unfortunately, there is no template argument in adjacency_list<> to specify Boehm GC's allocator. Does anyone … [View More]

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[statechart] history transitions make state-local-storage "un-cool"
by Mick Hollins 26 Jun '08

26 Jun '08

Apologies if this has been discussed before, but I couldn't find any mention of it: I am currently using the history facility of boost::fsm. I've discovered that when I re-enter a state, X, via a history transition I don't actually re-enter the same instance of X that I was in before, but instead enter a newly constructed instance of X. I just checked the UML spec regarding history transitions and it says that "Any necessary entry actions are performed", so given that boost::fsm uses … [View More]

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Re: [Boost-users] cross compiling boost for ARM
by Hughes, James 12 Aug '07

12 Aug '07

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of remi > Sent: 05 January 2007 14:44 > To: boost-users(a)lists.boost.org > Subject: [Boost-users] cross compiling boost for ARM > > > hi! > > I want to cross compile boost for an ARM processor. > For a pxa 270. but when i try to cross compile boost with > arm-linux-g++ , it dosen't work ... a proble with jam... > … [View More]

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[Serialization] Problem serialization of derived classes
by Andreas Willich 09 Aug '07

09 Aug '07

Hi there! I have a problem with the code in the attachment. I followed the documentation and the examples, but I did not get the code to work. Gcc produces a lot of failures that something is already instantiated in header files of the serialization library. Has someone a idea what I am doing wrong? My gcc version is 4.1.1-r3 and I am working on a gentoo x86 box. Andreas Willich

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[lambda][1.33.1] Lambda warnings after installing VS2005 SP1
by john.wismar＠autozone.com 01 Aug '07

01 Aug '07

I have just installed Service Pack 1 for VS2005, and am now getting a warning in some code using lambda::bind. There wasn't a warning previously, but I don't know if the issue is due to an update to the C++ standard library, a legitimate warning that they weren't flagging before, or a spurious warning. It looks like the issue is that I'm passing a function pointer, to bind. Is this a warning I should just ignore, or is this a legitimate issue? Thanks for your help! Here's a sample app,… [View More]

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BGL: INTERNAL COMPILER ERROR in VC7.1
by Yariv Tal 10 Jun '07

10 Jun '07

This one was already posted by Nicholas Burlett awhile back (see http://lists.boost.org/MailArchives/boost-users/msg06534.php) but I have some new info that may help. The problem: ========= When compiling code that uses the boost.graph library the VC7.1 compiler shouts: c:\boost_1_32_0\boost\mpl\aux_\preprocessed\plain\apply_wrap.hpp(48) : fatal error C1001: INTERNAL COMPILER ERROR As Nicholas already noted, this seems to be due to some compiler problem with the boost.graph … [View More]

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[BGL-Python] __len__ and __iter__ for property maps
by George Sakkis 21 May '07

21 May '07

I'm trying to build BGL-Python from SVN. I managed to build it successfully on Windows (VC 8.0) but I'm having problems with gcc 3.4 on Linux; although it does compile, it doesn't expose in Python two property map methods, __len__ and __iter__. I think I narrowed it down to the non-selection of a template specialization: // boost/graph/python/property_map.hpp namespace boost { namespace graph { namespace python { namespace detail { / * skip other stuff */ template<typename Class, … [View More]

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read_graphviz question
by Jeffrey Holle 26 Apr '07

26 Apr '07

I'm using the post 1.31.1 version of boost, which has a much nicer read_graphviz function. I'm wondering if there is a way to "ignore" unwanted properties, something akin to sending them to /dev/null. My present experience is that if an unexpected property is found, an exception is thrown. Is there a way to express that a given property is to be ignored? Better yet, is there a way to say that all unexpected properties are to be ignored?

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[boost::wave] MSVC 8 warning
by Ovanes Markarian 27 Mar '07

27 Mar '07

Hello, I would like to address this issue to boost::wave authors. First of all great lib! Many thanks! During the compilation with MSVC8 Express Edition I get a warning: c:\boost\include\boost-1_33_1\boost\wave\cpp_context.hpp(112) : warning C4355: 'this' : used in base member initializer list c:\boost\include\boost-1_33_1\boost\wave\cpp_context.hpp(106) : while compiling class template member function 'boost::wave::context<IteratorT,LexIteratorT>::context(const std::… [View More]

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[BGL] Reading GraphML
by Jens Müller 25 Mar '07

25 Mar '07

I tried to read a GraphML file using Douglas' code and the following: std::auto_ptr<boost::dynamic_property_map> string2string_gen(const std::string& name, const boost::any&, const boost::any&) { typedef std::map<std::string,std::string> map_t; typedef boost::associative_property_map< std::map<std::string, std::string> > property_t; map_t* mymap = new map_t(); // hint: leaky memory here! property_t … [View More]property_map(*mymap); std::auto_ptr<boost::dynamic_property_map> pm( new boost::detail::dynamic_property_map_adaptor<property_t>(property_map)); return pm; } int main(int argc, char* argv[]){ // create a typedef for the Graph type using namespace boost; typedef boost::adjacency_list<vecS, vecS, directedS> Graph; Graph g; std::ifstream input(argv[1]); boost::dynamic_properties properties(&string2string_gen); typedef graph_traits<Graph>::vertex_descriptor Node; typedef property_map<Graph, vertex_index_t>::type NodeID_Map; NodeID_Map node_id = get(vertex_index, g); boost::read_graphml(input, g, properties); } but when running it I get: Unrecognized attribute `xmlns' of element `graphml'. Ignoring... Unrecognized attribute `xmlns:y' of element `graphml'. Ignoring... Unrecognized attribute `xmlns:xsi' of element `graphml'. Ignoring... Unrecognized attribute `xsi:schemaLocation' of element `graphml'. Ignoring... Unrecognized attribute `yfiles.type' of element `key'. Ignoring... Unrecognized attribute `yfiles.type' of element `key'. Ignoring... Unrecognized element `y:ShapeNode' Unrecognized element `y:Geometry' Unrecognized element `y:Fill' Unrecognized element `y:BorderStyle' Unrecognized element `y:NodeLabel' Unrecognized element `y:Shape' terminate called after throwing an instance of 'boost::bad_any_cast' what(): boost::bad_any_cast: failed conversion using boost::any_cast /bin/sh: line 1: 31380 Abgebrochen ./src/graphml2 Core0bis10_1000.graphml The file contains nodes like this (what a bloat ...): <node id="n1"> <data key="d0" > <y:ShapeNode > <y:Geometry x="2.457598996954175" y="498.06375265283157" width="10.0" height="10.0"/> <y:Fill color="#FF0000" transparent="false"/> <y:BorderStyle type="line" width="1.0" color="#000000" /> <y:NodeLabel x="3.0" y="3.0" width="4.0" height="4.0" visible="true" alignment="center" fontFamily="Dialog" fontSize="12" fontStyle="plain" textC olor="#000000" hasBackgroundColor="false" hasLineColor="false" modelName="internal" modelPosition="c" autoSizePolicy="content"></y:NodeLabel> <y:Shape type="rectangle"/> </y:ShapeNode> </data> </node> I am not even really interested in the d0 properties ... What can I do? [View Less]

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[Serialization] issue with portable_binary_oarchive
by Dan Leibovich 16 Mar '07

16 Mar '07

Hi, I am trying to use the portable binary archive example. I need to serialize only integers and strings. I tried it on linux and solaris5.8. The result binary stream is not the same and deserialization fails. I used hex viewer and notice that the files are very similar except for some few differences which results from endienness issues. Can it be that the metadata is written differently on each platform. This is happens when I serialize derived class through a pointer to base class. (I … [View More]

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[statechart] - problem with sc::transition<> -> invalid use of 'boost::statechart::detail::no_context::no_function [with Event = jm::ffcp::ev_init]' to form a pointer-to-member-func
by Oliver.Kowalke＠qimonda.com 15 Mar '07

15 Mar '07

Hello, I get following error: /opt/boost/include/boost-1_33_1/boost/statechart/transition.hpp:33: error: invalid use of 'boost::statechart::detail::no_context::no_function [with Event = jm::ffcp::ev_init]' to form a pointer-to-member-function /opt/boost/include/boost-1_33_1/boost/statechart/transition.hpp:33: note: a qualified-id is required if I try to compile: #ifndef JM_FFCP_UNINITIALIZED_H #define JM_FFCP_UNINITIALIZED_H #include <boost/mpl/list.hpp> //#include <boost/… [View More]

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[Threads] Conditions and avoiding lengthy mutex locks (background loading for a game)
by Peter Mackay 11 Mar '07

11 Mar '07

Hello, I'm trying to use the Boost Threads library to help me implement a background loading system for a game I'm writing. I want to enqueue load requests while the main game thread is running, and have a separate thread load the data and pass back the appropriate objects. Currently when I enqueue a new request, I notify a 'something to do' condition, which my loading thread waits on. The trouble is, when I notify it, the loader could be loading in the background, and has a lock on the … [View More]

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[fusion2/phoenix2] polymorphic function objects return type
by Chris Weed 05 Mar '07

05 Mar '07

Hi, I have been looking at fusion2 and phoenix2, and I noticed fusion2 suggests using "result" as polymorphic function objects return type, but the phoenix2 documentation suggests "apply" in the examples. Are these two different things, will they be merged, or am I missing something? Thanks, Chris

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[Iterator, MSV8] iterator_adaptor fails with undefined class
by Kris Braun 04 Mar '07

04 Mar '07

Hi there, I'm using Boost 1.33.1. The following code compiles with MSVC7.1, but not with MSVC8: class Path { private: typedef std::vector< Path > PathList; public: class iterator : public boost::iterator_adaptor< iterator, PathList::const_iterator > { ... } MSVC8 gives this error: boost/type_traits/is_pod.hpp(34) : error C2139: 'fledge::Path' : an undefined class is not allowed as an argument to compiler intrinsic type trait '__is_pod' Any recommendations on a … [View More]

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[BGL] - filesystem graph
by Shams 04 Mar '07

04 Mar '07

Hi, I would like to know how to "best" represent a filesystem using BGL. In this case the filesystem I want to describe is the unix/linux filesystem and its various paths from the root node "/". My questions: 1. What kind of graph is this filesystem and what is best to use in BGL to describe this? 2. How can I also best describe symbolic links (symlinks) and what kind of graph would this be, does this graph defer from the above? 3. How can I describe the metadata of a file (including … [View More]

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(no subject)
by gzahl＠arcor.de 01 Mar '07

01 Mar '07

Hi, > Hello Manuel, >> Hi, >> >> Im defining a class with a multi_index_container as base. >> When i construct a instance of this class, and the >> multi_index_container is called, the program crashes. It even >> crashes, when i dont use it as a base class. > [...] >> This compiles just fine, but if i run the code i get the >> following backtrace after a Sigmentation Abort. It happens, >> when the queue::queue() is called. Someone a … [View More]idee whats it >> about? Im new to boost::multi_index, so maybe i misunderstud >> something? Thank you > > Well, what you're doing is AFAICS correct, so you shouldn't > be getting this crash. You haven't provided a complete > test program showing producing the crash, so I wrote one > myself after what you've shown and tried it locally, no > problems here. Could you please try the attached jung.cpp > file? Does it crash also? If it doesn't then there's more > to your program than you have described, maybe you can > send compilable program showing the issue. If jung.cpp > crashes, then could you please provide the following info? The Testprogramm jung.cpp does not crash on my machines (im testing on a ubuntu 6.10 and a debian 3.1 system, both working with g++ 4.0.2) I will try to get a example which reproduces my error, but in the meantime i was thinking about the libc stuff. Maybe this is the real problem thing? i changed to 4.0.2 from a 3.x version just some weeks ago, so maybe here is the problem, because some lib im using is not compiled with 4.0.2? is there a way i can get the compiler version a library was compiled with? > > 1. What system are you running this on? > 2. The stacktrace mentions a failed assertion in libc.so. Can > you see the source code that's causing the assertion? Maybe > it sheds some light. Im not sure about, where to see this sourcecode? scoped_lock(lightweight_mutex & m): m_(m.m_) { pthread_mutex_lock(&m_); } these are the lines alst mentioned in the backtrace "/usr/local/include/boost/detail/lwm_pthreads.hpp:72" from #5. But this is not what you meant, right? > 3. Can you try the attached lock.cpp file? Crash/no crash? > I didnt tried, because example worked fine. > Looking forward to your response, Thanks for help so far. I hope we can fix it soon. Ill go on, cut some working code out, which reproduces the error. > Joaquín M López Muñoz > Telefónica, Investigación y Desarrollo Manuel Jung Viel oder wenig? Schnell oder langsam? Unbegrenzt surfen + telefonieren ohne Zeit- und Volumenbegrenzung? DAS TOP ANGEBOT JETZT bei Arcor: günstig und schnell mit DSL - das All-Inclusive-Paket für clevere Doppel-Sparer, nur 44,85 inkl. DSL- und ISDN-Grundgebühr! http://www.arcor.de/rd/emf-dsl-2 [View Less]

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[signals] dropping ThreadingModel template parameter
by Frank Mori Hess 01 Mar '07

01 Mar '07

It seems that now that we drop locks before running slots, we can get by with using boost/detail/lightweight_mutex.hpp for our mutex. Since it is header-only, and apparently compiles to a null mutex if the compiler is in single-threaded mode, I don't see much need for a ThreadingModel template parameter on the signal class any more. I'm dropping it from thread_safe_signals. -- Frank

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boost::variant question
by Digvijoy Chatterjee 01 Mar '07

01 Mar '07

Hi, i have a boost::variant holding some C++ types which have to be inserted into the database : boost::variant<int, std::string, double > dbColumnValueVar; before i insert the value_type into the database I need to call a processing function which is overloaded for every datatype used in the variant ie. each of these functions are defined process ( int ); process ( std::string ); process ( double); template <class T> process(T); ..... what i do not understand is how do i use … [View More]

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[the Boost Graph library] no matching function : vertices(const Graph& g)
by Gerd Menche 01 Mar '07

01 Mar '07

Dear Boost users, I have come across this strange problem: After designing an interface to a library dealing with molecules (OpenBabel). I get the following compiler error: /usr/include/boost/graph/breadth_first_search.hpp: In function void boost::breadth_first_search(const VertexListGraph&, typename boost::graph_traits<G>::vertex_descriptor, Buffer&, BFSVisitor, ColorMap) [with VertexListGraph = OpenBabel::OBMol, Buffer = boost::queue<OpenBabel::OBAtom*, std::deque<… [View More]

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boost 1.33.1 + qt 3.3.7 free on linux
by misiu 01 Mar '07

01 Mar '07

Hello, I'm developing standard c++ application with boost libs: any, thread, file_system, lambda, regex and everything is fine. Then I'm adding Qt for GUI and on MS Windows still fine but on Linux I got very strange problem: compilation and linking without problems (even no warnings) but just after start program hangs (even not showing GUI window) but not crushes (no core dumped). Without boost dependent parts Qt program works fine and boost parts without Qt work fine as well. What do … [View More]

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[type_traits] is_function
by Cromwell Enage 28 Feb '07

28 Feb '07

Assuming a compiler supports is_function, will this metafunction check for the presence of member functions in a class? For example: struct Foo { void bar(); }; struct Baz { }; Given the right template argument, will is_function detect the bar() function in Foo but return false_ for Baz? If so, what is the right template argument? If not, are there any known workarounds? Cromwell D. Enage … [View More]

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[Boost-Users][serialization] Floating point precision
by jsanga＠cox.net 28 Feb '07

28 Feb '07

Is there a way to specify the precision of doubles when writing to xml_oarchive? Refer to the output snippet below. <Control class_id="3" tracking_level="0" version="1"> <Type>0</Type> <LowMZ>5.0499999999999998</LowMZ> <HiMZ>5.0999999999999996</HiMZ> I would like 5.05 and 5.1 for Low and High. Stepping through the code with the debugger I ended up in basic_text_oprimitive::save( const double t). … [View More]

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[Boost.MultiIndex] Problem using dataelement from derived class as key
by Manuel Jung 28 Feb '07

28 Feb '07

Hi, Im having a problem. I derive class B from class A. class a has the member A::id. I want to use this one as key for my MultiIndexContainer. But i get the following compiling errors: test.cpp:41: Fehler: Templateargument »&A::id« konnte nicht in »unsigned int B::*« umgewandelt werden test.cpp:42: Fehler: Templateargument 2 ist ungültig test.cpp:43: Fehler: Templateargument 1 ist ungültig test.cpp:44: Fehler: Templateargument 2 ist ungültig Sorry it on german. A testfile for … [View More]

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[boost][circular_buffer] problem using copy contructor
by Andreas Rose 28 Feb '07

28 Feb '07

Hello, I'm new to circular_buffer. After reading the documentation i expect the following should work: const int c = 5; boost::circular_buffer<int> cb1(c); assert(cb1.capacity() == c); boost::circular_buffer<int> cb2(cb1); assert(cb2.capacity() == c); //failed, capacity() returns 0 But it does'nt work. After looking into the code of circular_buffer, i think the copy c'tor should be changed into something like this: circular_buffer(const circular_buffer<T, Alloc>& … [View More]

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Problem using regex library in Windows/cygwin
by Diego Molla 28 Feb '07

28 Feb '07

Hi, I have a problem using the Boost regex library. I have isolated the problem to the attached piece of code. For some reason the output returned by the function that uses regex is garbage. I have tested the same program on a Linux version of boost and it works fine. I wonder if the problem is on the Windows installation. Could someone using Windows or Cygwin test this and tell me if it works? I've just re-installed the cygwin version (1.33.1-3) and I still get the same error. … [View More]

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[graph] patch to automatically build libbgl-viz.so and libbgl-viz.a
by David Baird 28 Feb '07

28 Feb '07

Hi, I'm interested in helping make the BGL easier to use right out-of-the-box. But, I'm not an expert at Boost (or Jamfiles) yet, so please guide me if this is wrong. I tried to patch the Jamfile so that it automatically builds the Graphgiz parser libraries (libbgl-viz.so and libbgl-viz.a). I only tested Jamfile (not Jamfile.v2) on some Gentoo boxes with gcc-4.1.1 and gcc-3.3.5 and it worked nicely. Some other future improvements I would like to do are to improve the Graphviz parser (to be … [View More]

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[program_options] unsigned variables silently cast
by Torrey Pines 28 Feb '07

28 Feb '07

Hi With the current implementation, unsigned variables accept negative values, that get silently cast. E.g. on my platform, if "--length" expects size_t, --length -32 assigns it a value 4294967264 without warnings or errors. This behavior surprised me, and I'm using a workaround (parsing an int, and checking its range manually). However, is this an intended feature of the library? Thanks

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[program_options] disable partial matches
by Torrey Pines 28 Feb '07

28 Feb '07

Hi With the current implementation, the user does not have to supply the full option names, e.g. "--he" is as good as "--help", unless there is an ambiguity. Is there any way to disable this, i.e. allow only full matches? Thanks

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[program_options] checking the presence of required arguments
by Torrey Pines 28 Feb '07

28 Feb '07

Hi My program has a bunch of required arguments. I grouped them into one options_description: options_description required("Required options"); required.add_options() /* .... */ ; // ... options_description desc("Allowed options"); desc.add(required).add(other); I'd like to check that all required arguments are in fact supplied without having to do if(vm.count("arg1") == 0) { cerr << "usage error: arg1 is required\n"; return 1; } for each of them. Any suggestions? Thanks

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boost::any template argument deduction
by Digvijoy Chatterjee 28 Feb '07

28 Feb '07

Hi, I have a function template like : template <class A> A what_type ( const boost::any &operand ){ A a; a = boost::any_cast<a>(operand); return a; } The idea is to provide the client code an easy way extract the type hidden by the boost::any value, Now there is no way to make the compiler deduce the type to return from an expression like below: std::string s = "hello"; boost::any a = s; some_op( what_type(a) ); //calls some_op(string &); … [View More]

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[MPL] Problem with vector
by Daniel 28 Feb '07

28 Feb '07

Hi, I have few Adapter classes. Each of them provide typedef operations which specifies which operations that Adapter supports (vector_c, with 0 or 1 at appropriate positions). I want to assert that two Adapters support different operations. However, my code doesn't compile. Any ideas? Daniel template<unsigned int N1, unsigned int N2> struct Adapter { typedef vector_c<unsigned int, N1, N2> operations; }; template<class TAdapter1, class TAdapter2> struct Check { … [View More]

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[signals] slot<Signature>, slot::track() and bind syntactic sugar
by Frank Mori Hess 27 Feb '07

27 Feb '07

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I've added template parameters to the slot class in thread_safe_signals for specifying its signature, as slot<Signature> or slot1<R, T1>, etc. So now slots can be bound to each other. I've also dropped the automatic discovery of tracked objects, and added slot::track() functions. There is now some syntactic sugar for bind, if a slot constructor is called with more than one argument, then the arguments will automatically be … [View More]

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[multi index] warning when used in copy constructor: should be explicitly initialized
by Christoph 27 Feb '07

27 Feb '07

Using gcc with option -W I get the following warning when using a Boost.MultiIndex container inside a copy constructor: /usr/local/include/boost-1_33_1/boost/multi_index_container.hpp: In copy constructor 'boost::multi_index::multi_index_container<Value, IndexSpecifierList, Allocator>::multi_index_container(const boost::multi_index::multi_index_container<Value, IndexSpecifierList, Allocator>&) [with Value = ListenMonitor::ListenZeile, IndexSpecifierList = boost::multi_index::… [View More]

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Possible bugs in date_time package
by Gregory J. Sharp 27 Feb '07

27 Feb '07

I'm trying to use the date_time/ptime module to parse strings. Platform: MacOS X 10.4.7 on Intel Compiler: gcc 4.0.1 I have three potential bugs, so far. Perhaps I'm unreasonable in hoping that the following strings should be acceptable to time_from_string. 1. time_from_string( "2006-12-06" ) != time_from_string( "2006-12-06 00:00:00" ) 2. time_from_string( "2006/12/06" ) throws an exception (probably related to 1) even though time_from_string( "2006,12,06" ) doesn't throw. 3. … [View More]

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multi_index uses serialization?
by Javier Gonzalez 27 Feb '07

27 Feb '07

Hi, I have a simple question. Isn't there a way to create multi_indices without using the serialization library? I don't intend to stream them! thanks, Javier Gonzalez

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State of the Endian library
by Mateusz Loskot 27 Feb '07

27 Feb '07

Hi, What's the state of the Endian library announced [1] by Beman Dawes? Is there any plan to include it to the Boost collection? May be it's already there, but I can not find it? [1] http://thread.gmane.org/gmane.comp.lib.boost.devel/143279 Cheers -- Mateusz Loskot http://mateusz.loskot.net

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shared_ptr and RTTI
by Florin Trofin 27 Feb '07

27 Feb '07

Hello, A few years back, boost::shared_ptr did not require RTTI. I recently discovered that it does now. I understand that there are some benefits that RTTI brings to the new implementation, but I would have expected that there is some compile flag that can be turned on/off. Florin.

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[BGL] How to use an array in bundled property?
by Shufei Fan 27 Feb '07

27 Feb '07

I defined an double array inside bundled vertex property, and have trouble finding ways of accessing it. Neither can I find any where in the document an example on it. Your input will be much appreciated! my graph is defined as follows: struct Node{ // this is hard to access double mode[3]; }; struct Edge{ //no problem access them double nPixels; unsigned short nTh;}; typedef boost::adjacency_list< boost::vecS, boost::vecS, boost::bidirectionalS, Node, Edge> Graph; //… [View More]Graph object colGraph Graph colGraph; I have no problem with accessing the 'nPixels' in Edge property, boost::property_map<Graph, double Edge::*>::type ew = get(&Edge::nPixels, *colGraph);//edge weight But I am in a great deal of trouble finding ways of accessing 'mode' in Node property. //compiler error here boost::property_map<Graph, double Node::*>::type nm = get(&Node::mode, *colGraph);//node modeerror message is : //---------------------------------------------------- c:\...\xxx.cpp(236) : error C2440: 'initializing' : cannot convert from 'boost::property_map<Graph,Property>::type' to 'boost::bundle_property_map<Graph,Descriptor,Bundle,T>' with [ Graph=boost::adjacency_list<boost::vecS,boost::vecS,boost::bidirectionalS,Node,Edge>, Property=double (Node::* )[3] ] and [ Graph=Graph, Descriptor=boost::property_map<Graph,double Node::* >::descriptor, Bundle=Node, T=double ] No constructor could take the source type, or constructor overload resolution was ambiguous//---------------------------------------------------- neither the following works(I added '[3]' in the parameter list): boost::property_map<Graph, double Node::*[3]>::type nm = get(&Node::mode, *colGraph);//node mode This time errors are raised in the 'property.hpp' file, they are: //---------------------------------------------------- c:\Boost\include\boost-1_33_1\boost\pending\property.hpp(40) : error C2825: 'PropertyTag::kind': cannot form a qualified name c:\Boost\include\boost-1_33_1\boost\graph\properties.hpp(198) : see reference to class template instantiation 'boost::property_kind<PropertyTag>' being compiled with [ PropertyTag=double Node::* [3] ] c:\shufei\VCProjects\edison\segm\GA.cpp(236) : see reference to class template instantiation 'boost::property_map<Graph,Property>' being compiled with [ Graph=Graph, Property=double Node::* [3] ]c:\Boost\include\boost-1_33_1\boost\pending\property.hpp(40) : error C2039: 'kind' : is not a member of 'operator``global namespace'''c:\Boost\include\boost-1_33_1\boost\pending\property.hpp(40) : error C2146: syntax error : missing ';' before identifier 'type'c:\Boost\include\boost-1_33_1\boost\pending\property.hpp(40) : error C2955: 'boost::type' : use of class template requires template argument list c:\Boost\include\boost-1_33_1\boost\type.hpp(14) : see declaration of 'boost::type'c:\Boost\include\boost-1_33_1\boost\pending\property.hpp(40) : fatal error C1903: unable to recover from previous error(s); stopping compilation//----------------------------------------------------thanks, _________________________________________________________________ Connect to the next generation of MSN Messenger http://imagine-msn.com/messenger/launch80/default.aspx?locale=en-us&source=… [View Less]

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faq How to compile graph?
by fcvcnet 27 Feb '07

27 Feb '07

Hi all, I know BGL just a few days. I need yours help. Now I only want to use the graph in the boost1.33.1 , how can I compile the only one component graph in vc6 or vs2005. So much thanks to your detail reply. Thanks again.

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[lambda] beginner's woes
by Imre Palik 27 Feb '07

27 Feb '07

Hi, I try to use boost::lambda in the following function: string build_headers(shared_ptr<connection> conn, vector<wstring> headers) { if (headers.empty()) return ""; return accumulate(++headers.begin(), headers.end(), string(1, '\'') + conn->quote(headers[0]) + '\'', (_1 + ", '" + bind(&connection::quote, var(conn), _2) + '\'')); } and wisual studio gives me the following error message error C2664: 'boost::… [View More]

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[signals] slot with no SlotFunction template parameter
by Frank Mori Hess 26 Feb '07

26 Feb '07

I'm implementing a more feature-full slot class with some of the things that have been discussed recently. In particular, it is templated only on signature. It uses a templated constructor to store the slot function in a pimpl object that is templated by both signature and slot function type. So now I'm about to rip out the SlotFunction parameter everywhere from thread_safe_signals, as there no longer seems to be any need for it. I feel like I might be overlooking something though. … [View More]

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[signals] thread-safe post-disconnect() cleanup
by Frank Mori Hess 26 Feb '07

26 Feb '07

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 We could implement a thread-safe post-disconnect callback by using the existing tracking functionality. That is, the connection body could hold a "cleanup" shared_ptr with a custom deleter. The custom deleter would run the user's cleanup callback. A weak_ptr copy of the cleanup shared_ptr would be kept just like it was any other tracked object. When disconnect() is called, the cleanup shared_ptr would be reset. If the signal is being … [View More]

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Re: [Boost-users] [boost::any] - reference vs pointer
by Benjamin Winkler 26 Feb '07

26 Feb '07

References can not be copied. Thus, you can't make boost::any contain a reference (which is what mean when you write boost::any<double&>, I assume). In your example, msgargs.push_back(dref) calls the any-constructor any(const T&) with T being double, and this copies the value, not the reference itself. When you call msgargs.push_back(dptr), it calls the any(const T&) with T being double*. The value is copied again, only this time, the value is a pointer. Benjamin Winkler &… [View More]

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[FileSystem] Getting modified date and time from a file?
by Lawrence Spector 26 Feb '07

26 Feb '07

Does boost provide a portable way to do this? I didn't see an obvious way; I was hoping others might have ideas. Thanks in advance, Lawrence

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[program_options] Documentation of configuration file format?
by Tarjei Knapstad 26 Feb '07

26 Feb '07

I can't seem to find any documentation on what kind of file formats are accepted when calling boost::program_options::parse_config_file(...) Am is missing it or is it missing? :) -- Tarjei

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BoostCon'07 Registration Now Open
by info＠boostcon.com 26 Feb '07

26 Feb '07

The following message is a courtesy copy of an article that has been posted to comp.lang.c++.moderated,comp.std.c++,comp.lang.c++ as well. I'm pleased to announce that the official website for the inaugural Boost conference is up and registration is open: http://www.boostcon.com Due to the very high quality of the submissions we've received, our program committee has been able to assemble a lineup of speakers and topics the likes of which I haven't seen anywhere (http://www.boostcon.… [View More]

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