February 2008 - Boost-users - lists.preview.boost.org

WG: Boost Build
by Klett, Stefan 18 Feb '08

18 Feb '08

Hi fellow list subscribers, The last days I have been busy to build a build-environment for a library project with boost build - I am new to boost and have no previous experience with boost build - what may account for the following problems I ran into The proposed structure of the library project is like this: Project-root | \ \ \ Include src doc examples / | testcase1 testcase2 ... Now I need some help to make bjam perform the following tasks: 1) build the library (this one works already) 2) generate a doxygen based documentation out of the the *.cpp files in src 3) build the testcases in the "testcaseX" directories For the time being I'm lacking the knowledge how to build targets (the above tasks separately - I tried to use the "explicit" keyword but it seems that missed something - bjam works trough all targets given in the Jamroot file which I placed in the "project-root" directory - could somebody please give me an example how to use targets and "explicit" correctly Further I need an hands on example how to get along with the doxygen documentation - my efforts up to now look like this - but this actually seems to do nothing at all Import doxygen : doxygen ; doxygen.doxygen doc : geneva : [ glob include/*.h ] #: requirements <include>include : ; The Question is : how do I extract the information from the files in src and write the doxy docu to doc ? And last but not least : how is the correct syntax for building sources in subdirectories - where have I to put the Jamfiles and how to I tell bjam to look for them ? Many Thanks in advance Best regards Stefan -------------------------------------------------------- Stefan Klett (Dipl. Informatiker) | E-mail: stefan.klett(a)kit.edu Forschungszentrum Karlsruhe / KIT | Web: http://www.fzk.de SCC Steinbuch Centre for Computing| Phone: +49 (0)7247 828649 Hermann-von-Helmholtz-Platz 1 | Fax: +49 (0)7247 824972 D-76344 Eggenstein-Leopoldshafen | Mobile: +49 (0)176 20317250 -------------------------------------------------------------------

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Boost.IOStreams and Custom filters on strings
by Stefan Arentz 18 Feb '08

18 Feb '08

I've written a really simple aggregate_filter that runs the world famous and highly secret ROT13 encryption. This filter works fine when I use a file_sink and file_source. But I really just want to run this on a bunch of string buffers. Unfortunately it does not work, the destination string is always empty. Does anyone understand why? Here's the code, tested against Boost 1.34.1 on OS X 10.5.1: #include <iostream> #include <memory> #include <string> #include <boost/iostreams/copy.hpp> #include <boost/iostreams/device/back_inserter.hpp> #include <boost/iostreams/filter/aggregate.hpp> #include <boost/iostreams/filtering_stream.hpp> template< typename Ch, typename Alloc = std::allocator<Ch> > class basic_rot13_filter : public boost::iostreams::aggregate_filter<Ch, Alloc> { private: typedef boost::iostreams::aggregate_filter<Ch, Alloc> base_type; public: typedef typename base_type::char_type char_type; typedef typename base_type::category category; typedef std::basic_string<Ch> string_type; public: basic_rot13_filter() { } private: typedef typename base_type::vector_type vector_type; void do_filter(const vector_type& src, vector_type& dest) { for (size_t i = 0; i < src.size(); ++i) { dest.push_back(src[i] + 13); } } }; typedef basic_rot13_filter<char> rot13_filter; typedef basic_rot13_filter<wchar_t> wrot13_filter; int main() { std::string src = "SourceText"; boost::iostreams::filtering_istream in; in.push(boost::make_iterator_range(src)); std::string dst; boost::iostreams::filtering_ostream out; out.push(rot13_filter()); out.push(boost::iostreams::back_inserter(dst)); boost::iostreams::copy(in, out); std::cout << dst << std::endl; return 0; }

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boost::serialization and platform portability
by Mark Schlegel 18 Feb '08

18 Feb '08

Boost User list: I have a question about boost::serialization and portability. When I read in the overview for this feature at http://www.boost.org/libs/serialization/doc/overview.html point 7 states that "Data Portability - Streams of bytes created on one platform should be readable on any other". I'm trying to clear up how far portability goes. I've tested serialization on two different hardware platforms (Intel Linux with Boost 1.34.1 and Sparc Solaris with Boost 1.33.1) which have different endians. The archiving writes and reads fine as long as the reading is done on the newer or equal version of Boost. Basically I wrote a serialization file with boost::archive::text_oarchive on the Solaris box and ftped the file to the Linux host and read it in fine. But going the other way (1.34.1 -> 1.33.1) aborted which is understandable because a archive version level change (3 vs 4) existed between those. So is readability assured by serialization as long as you're going from an older or equal version of boost? We can handle our maintaining the very latest boost version in our code and customers would send us their archives for testing and they'd either have the same or older version of boost in their copy. Their code would never be newer than ours. If this is obeyed will their archives always be readable by our code? Mark

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BGL and interactive visualization
by mbn 18 Feb '08

18 Feb '08

Hi, Maybe this is an old topic but I can't find related answers. I have some data containing certain "entities" related to others by one or more attributes. For example, Alice's cat may be connected to Bob's dog because both are named "Bill". Also, they can be connected because they live in the same county. Furthermore, Bob's dog can be connected to Chuck's bird because they are of the same color Something like this: (A'sC)--------------(B'sD)-----------------(C'sB) Name=Bill Color=Beige County=CD The issue is, the attributes connecting entities can be hundreds or even thousands, so creating a graphviz file showing all those connecting attributes in the edges will result in a mess. Instead, I would like to create an application such that only the vertices (with a label inside) and the edges (without nothing) are initially shown, and when the user double clicks on a specific edge then some window can appear showing all the attributes causing X and Y to be connected in the graph. I know I can create the graphs using BGL, but once I have the graphs I do not know what library to use in order to visualize it Can somebody help? Perhaps there is a different/better way of doing the same with a different tool like GraphML + Some Visualization program? Thanks, Mark -- View this message in context: http://www.nabble.com/BGL-and-interactive-visualization-tp15514275p15514275… Sent from the Boost - Users mailing list archive at Nabble.com.

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[boost-users] [bjam BOOST_AUTO_LINK_NOMANGLE]
by chun ping wang 18 Feb '08

18 Feb '08

I want to build msvc library by defining BOOST_AUTO_LINK_NOMANGLE but i also want to specify multithreaded build. Example I want my thing to auto link to boost_python-mt.lib Is their a way to do this. BOOST_AUTO_LINK_NOMANGLE only links to boost_python.lib Thanks.

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random variate_generator, call_traits...
by e r 18 Feb '08

18 Feb '08

Hi All, I have classes A and B as random distributions i.e. they have a member function operator()(UniformRandomNumberGenerator&). I choose to make UniformRandomNumberGenerator a class template instead of a member function template (why? because in my non-simplified code A::operator()(...) is virtual). B has a member variable of type A that it uses for its implementation. Passing UniformRandomNumberGerator& into the nested object's A::operator()(...) causes a reference to reference problem that I solve with call_traits. fine? I want to wrap a boost::variate_generator around UniformRandomNumberGenerator and B. The variate_generator does not pass UniformRandomNumberGenerator& to A::operator()(...) but - i guess - a decorated version of it. so I have to specify A<Decoration> instead of A::<UniformRandomNumberGenerator> and likewise for B. I don't like this manual fix (I have to look at the compiler errors to figure out Decoration). Maybe I could overload A and B's operator()(...) with something like operator()(Decoration<UniformRandomRandomNumberGenerator>) but have not succeeded. Any better suggestion? #include <boost/call_traits.hpp> template<class UniformRandomNumberGenerator> class A{ public: typedef UniformRandomNumberGenerator urng_type; typedef double input_type; typedef double result_type; typedef urng_type argument_type; result_type operator()(argument_type u){return u();}; }; template<class UniformRandomNumberGenerator,template<class> class Impl> class B{ public: typedef UniformRandomNumberGenerator urng_type; typedef Impl<urng_type> impl_type; typedef double input_type; typedef double result_type; typedef typename impl_type::argument_type impl_argument_type; typedef typename boost::call_traits<impl_argument_type>::reference argument_type; result_type operator()(argument_type u){return impl(u);}; private: impl_type impl; }; #include "A.hpp" #include <boost/random.hpp> #include <boost/random/variate_generator.hpp> #include <boost/random/uniform_real.hpp> typedef boost::mt19937 urng_type; typedef boost::uniform_real<> rdu01_type; typedef boost::variate_generator<urng_type&,rdu01_type> urng01_type; typedef A<urng01_type> a0_type; typedef B<urng01_type,A> b0_type; typedef boost::variate_generator<urng01_type&,b0_type> rg0_type; typedef boost::uniform_01<boost::random::detail::pass_through_engine<urng01_type&>,double> pass_through_engine_type; //manual fix, far from ideal typedef A<pass_through_engine_type> a1_type; typedef B<pass_through_engine_type,A> b1_type; typedef boost::variate_generator<urng01_type&,b1_type> rg1_type; int main(){ urng_type urng; rdu01_type rdu01; urng01_type urng01(urng,rdu01); b0_type b0; std::cout << b0(urng01) << std::endl; //OK // rg0_type rg0(urng01,b0); // std::cout << rg0() << std::endl; // Error no match for call to ‘(B<boost::variate_generator<boost::random::mersenne_twister<unsigned int, 32, 624, 397, 31, 2567483615u, 11, 7, 2636928640u, 15, 4022730752u, 18, 3346425566u>, boost::uniform_real<double> >, A>) (boost::uniform_01<boost::random::detail::pass_through_engine<urng01_type&>, double>&)’ candidates are: double B<UniformRandomNumberGenerator, Impl>::operator()(typename boost::call_traits<typename Impl<UniformRandomNumberGenerator>::argument_type>::reference) [with UniformRandomNumberGenerator = boost::variate_generator<boost::random::mersenne_twister<unsigned int, 32, 624, 397, 31, 2567483615u, 11, 7, 2636928640u, 15, 4022730752u, 18, 3346425566u>, boost::uniform_real<double> >, Impl = A] b1_type b1; rg1_type rg1(urng01,b1); std::cout << rg1() << std::endl; //OK return 0; }

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Re: [Boost-users] Another desperate request for help with a simple IOStreams sink and filter
by Chad Walters 18 Feb '08

18 Feb '08

Jonathan, A couple thoughts: 1. One of the first confusions that I naively had when I first approached the library was that classes that had close() methods did not necessarily model Closable. I am not sure if this means that "Closable" is a bad name and should be changed, but it might be worth calling out this distinction more pointedly in the documentation. 2. Perhaps for filtering streams, it would be best to make sure that closing the stream would close all the filters and flush the device. Would that solve this issue? Or is that already the current behavior? Chad Jonathan Turkanis wrote: The problem is that filtering_stream does not model Closable, so close() is a no-op. This is counterintuitive and probably represent a less than ideal design, but when I wrote the library I couldn't think of a satisfactory way to define close() for a filtering stream. You might think that the way to define close() would simply be to close all the filters and devices in the chain. Unfortunately, this is not correct. The reason is that while filters are designed to be reusable, devices are in general one-use only. For example, when a compression filter is closed, it is expected to be in a state where it can be used to compress a fresh stream of data. But when a file is closed, it is not reset to the state it was in when it was first opened: it has to be manually reopened with a new user-provided pathname. So simply closing all the filters and devices in the chain would leave the chain in an unusable state. The closest I could come to defining a non-trivial close() for filtering_streams was to have close() call pop() -- in effect, closing all the filters and discarding the final device. However, my feeling was that this behavior would be considered counterintuitive. I knew this could cause problems with copy, but I decided to wait for user feedback before making any changes. The issue never came up, and I forgot about it until now. It could be that not many are using the library, as you suggest, or that people discovered that you can solve the problem by calling reset() or pop() -- as you heard on the IRC channel -- and never bothered to bring it up on this list. I've created a ticket for this issue: http://svn.boost.org/trac/boost/ticket/1624. At the very least it should be a FAQ. > Is anyone actually using the library? I can't believe I'm the first > finding a bug like this in a 5 year old library. > > S. -- Jonathan Turkanis CodeRage http://www.coderage.com

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Gentoo: recent emerge gives me PIC errors
by Jason Weber 18 Feb '08

18 Feb '08

On my last emerge, I believe I got a new set of boost libs (amd64). Now my project is getting a PIC problem. All my code use compiles with -fPIC, so is this no longer the case with boost on Gentoo and is there a way to turn it on? I tried some various USE flags but nothing seems to make a difference. Or is that not the problem? ccache g++ -fPIC -DFE_USE_SSE=2 -msse2 -march=k8 -pipe -shared -o /mnt/raid/symroot/proj/fe/main/lib/x86_64_linux_debug/libfePlatform.so -DFE_DOUBLE_REAL=0 -ftemplate-depth-60 -ansi -D_REENTRANT -D_POSIX_REENTRANT_FUNCTIONS -DZT_POSIX -pipe -D_DEBUG -g2 -Wall -DGCC_HASCLASSVISIBILITY -fvisibility-inlines-hidden -fvisibility=hidden -Winvalid-pch -I/mnt/raid/symroot/proj/fe/main/ext -I/usr/X11R6/include -I/mnt/raid/sym/root/proj/fe/main/src -I/mnt/raid/symroot/proj/fe/main/lib/x86_64_linux_debug -I/mnt/raid/symroot/proj/fe/main/lab /mnt/raid/symroot/proj/fe/main/obj/x86_64_linux_debug/src/platform/debug.o /mnt/raid/symroot/proj/fe/main/obj/x86_64_linux_debug/src/platform/DL_Loader.o /mnt/raid/symroot/proj/fe/main/obj/x86_64_linux_debug/src/platform/DualString.o /mnt/raid/symroot/proj/fe/main/obj/x86_64_linux_debug/src/platform/Exception.o /mnt/raid/symroot/proj/fe/main/obj/x86_64_linux_debug/src/platform/Result.o /mnt/raid/symroot/proj/fe/main/obj/x86_64_linux_debug/src/platform/String.o /mnt/raid/symroot/proj/fe/main/obj/x86_64_linux_debug/src/platform/System.o /mnt/raid/symroot/proj/fe/main/obj/x86_64_linux_debug/src/platform/SystemTicker.o -ldl -L/mnt/raid/symroot/proj/fe/main/lib/x86_64_linux_debug -ansi -lpthread -lrt -pipe -lm -lc -lcrypt -ldl -lboost_regex-mt -lboost_thread-mt -lboost_filesystem-mt -L/mnt/raid/symroot/proj/fe/main/lib/x86_64_linux_debug -L. -L/home/symhost/sym/bulk/amd64obj/fe/lib/x86_64_linux_debug /usr/lib/gcc/x86_64-pc-linux-gnu/4.1.2/../../../../x86_64-pc-linux-gnu/bin/ld: /mnt/raid/symroot/proj/fe/main/obj/x86_64_linux_debug/src/platform/String.o: relocation R_X86_64_PC32 against `boost::re_detail::perl_matcher<__gnu_cxx::__normal_iterator<char const*, std::basic_string <char, std::char_traits<char>, std::allocator<char> > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >, boost::regex_traits<char, boost::cpp_regex_traits<char> > >::find()' can not be used when making a shared object; recompile with -fPIC /usr/lib/gcc/x86_64-pc-linux-gnu/4.1.2/../../../../x86_64-pc-linux-gnu/bin/ld: final link failed: Bad value collect2: ld returned 1 exit status

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[flyweight] Review summary
by Ion Gaztañaga 17 Feb '08

17 Feb '08

Hi to all, I've just written a summary of the flyweight review that tries to point out the main requests, questions and comments from reviewers and Joaquin's replies to those. If someone thinks I've missed some important point, please let me know. Joaquín is already correcting the pointed issues and thinking about alternatives on the keyed_flyweight issue. I hope we can definitely solve them satisfactorily in a short period of time. Here we go: -------------------------- Beginning of summary -------------------------- ------------------------- *Tim Blechmann’s review:* ------------------------- Design: Good. Suggests using read-write locks to improve concurrency since most operations will be searches. Implementation: fine Documentation: good Usefulness: quite useful to reduce memory footprint. Try to use the library: no Effort: Read documentation and compare it with his own implementation Knowledgeable about the problem domain: yes Accept the library: yes This reviews starts a thread about the correct read-write lock implementation for flyweight: 1) Joaquín points out that the library is based on insert(x) so a good candidate can be: readwrite_lock l(mutex); l.read_lock(); if(h=find(x))return h; else{ l.unlock(); l.write_lock(); h=insert(x); } Unfortunately read-write locks were removed due to a bug so this issue will be put under Future Work section for now. 2) Alberto Ganesh Barbati: suggests using hinted insert to improve performance in cases where find(x) fails and try to get a O(1) insertion. He also suggests using promotion or/and upgradable mutexes. 3) Joaquín thinks promotion/upgradable mutexes are not necessary. Read-write locks/upgradability/hints will need more thinking to maintain current policy orthogonality and the issue needs time. As mentioned, the issue will be revised when rw locks are available in Boost. Review manager note: I think that using “hint” needs atomic convertibility, because the “hint” can be invalidated by an erasure between unlock_sharable() and lock_sharable() and hint insertion does not guard against invalidated hints, but only against non invalidated but non-optimal hints. ------------------------- *John Reid’s review:* ------------------------- Design: Very good. Suggests intermodule_holder as the default holder. Implementation: Ok. Documentation: Clearly written and well thought out. He would like to see more examples and the inclusion of test code. Usefulness: High Used the library: No Effort: A quick read through the tutorial and the examples Knowledgeable about the problem domain: Not a design patterns expert but using C++ for 15 years. Accept the library: yes 1) Joaquín replies that intermodule_holder performs a way more expensive static initialization process than static_holder (needs shared memory). Another reason for not including this is that Boost.Interprocess (on which intermodule_holder depends) is not universally supported. Agrees to improve examples. 2) John suggests documenting intermodule_holder limitations 3) Joaquín agrees documenting these limitations ------------------------- *Marcus Lindblom’s review* ------------------------- Design: Very nice. Comments: namespace should be boost::flyweight. Factory should be called store Implementation: Not looked at thoroughly. Documentation: Great! Comments: the reference page, the first header ("boost/flyweight.hpp") doesn't link to anything? flyweight.hpp page misses to mention the tag argument in the first list of parametrization. Usefulness: High. Used the library: Nope. Effort: Quick reading. (1h) Knowledgeable about the problem domain: Yes Accept the library: Yes 1) Joaquín says that namespace issues are related to compiler bugs and the namespace conforms Boost rules explained at "For those who are really interested in namespaces" at http://tinyurl.com/ywb9n7 Factory name was chosen because most descriptions of the flyweight design pattern use this same terminology: http://tinyurl.com/ys5k3q Agrees to fix documentation problems with Firefox. ------------------------- *Matias Capeletto’s review* ------------------------- Design: Great. Implementation: Quick look. Documentation: Good. Typo spotted. Usefulness: High Used the library: gcc 4.1.3, under Linux Effort: Followed the library progress from the beginning Knowledgeable about the problem domain: Yes Accept the library: Yes 1) Joaquín: Typo fixed David Sankel’s review Design: Very well designed. Suggests a configuration option for equality segmantics. Implementation: He hasn't looked at much code, so I have no opinion here Documentation: Good Usefulness: Good Used the library: No Effort: An in depth study of the documentation Knowledgeable about the problem domain: Not until this review Accept the library: Yes 1) Joaquín says it’s trivial to override the default equality on a per case basis: typedef flyweight<whatever,...> fw_t; inline bool operator==(const fw_t& x,const fw_t& y) { return &x.get()==&y.get(); } ------------------------- *Vicente Botet’s review* ------------------------- Design: Good. Issues: * The tests performed on example5 should be extended with a intermodule_holder specifier. Joaquín’s answer: there is no need for that since it’s only performed in the initialization. * On platforms on which static variables are unique inter DLL the intermodule_holder specifier type can be a static_holder_class. Joaquín’s answer: Ok. * Holder specifier renaming. Maybe static_holder by module_holder, and intermodule_holder by process_holder? Joaquín’s answer: Agrees to revise names but he’s not found good alternatives. * Add an exclusive core specifier Joaquín’s answer: Added to Future Work section. Implementation: Quite good * Minor correction The documentation states that the ..._specifier must be a ..._marker, but this is not needed for the ..._class Joaquín’s anwswer: This ability used to be documented at the reference, but I've just checked and it is no longer there, I'll restore that bit. * refcounted_value is a class that could be public. Why it is declared in the namespace detail. Joaquín’s answer: It is an implementation detail, the user won't ever be exposed to it. * could you explain why detail::recursive_lightweight_mutex is needed and boost::detail::lightweight_mutex is not used directly? Joaquín’s answer: Recursive mutexes are needed when constructing composite complexes with flyweight<>. Documentation: Good. Issues: * Some more elaborated examples suggested. Joaquín’s answer: I'll try to extend the examples section. * intermodule_holder specifier: A reference to a document explaining the problem with platforms not ensuring the unicity of static variables when DLL are used will be welcome. Joaquín’s answer: I'm no expert here, but I'd say that platforms without static var unicity across dynamic modules are the majority rather than the exception. * Reference section: The reference section was much more hard to follow. I think that the interactions between the different classes are very hard to describe using the current style. Joaquín’s answer: It tries to keep the level of formality you find at the C++ standard. The idea is you go to the reference for exact, authoritative information. * An implementation section will help to understand how all this works, describing the interactions between the core and the policies. Joaquín’s answer: I'd much prefer to concentrate on improving the part on extending the library without disclosing too much about how things are assembled internally. * Add performance section Joaquín’s answer: Ok. * Rational: Adding of the map versus set problem explanation.??? Usefulness: Good Used the library: No. Effort: In-depth reading of the docs and implementation Knowledgeable about the problem domain: Yes Accept the library: Yes ------------------------- *Neil Hunt’s review* ------------------------- Design: Good Implementation: Good Documentation: He didn't read it all closely. * Some performance indicators or at least discussion of the tradeoff of extra hashing vs reduced dynamic allocations would be useful. Joaquín’s answer: ok Usefulness: Useful Used the library: No Effort: A moderate investigation. Knowledgeable about the problem domain: Yes Accept the library: Yes ------------------------- *Alberto Ganesh Barbati’s review* ------------------------- Design: Very good. Issues: * It doesn't fully grasp the essence of the flyweight pattern because of a major flaw. The flaw is the fact that an object needs to be created in order to check whether an equivalent flyweight exists or not. Implementation: Well done. Issues: * I strongly disagree with the choice of the term "factory" for a component that actually only acts as a storage. Documentation: Very well written. Issues: * The policies are indeed properly described, but the bare description is not very helpful in showing how to write a new policy Usefulness: Useful if the flaw I described before could be addressed Used the library: gcc 3.4.5 (mingw) Effort: A couple of hours. Knowledgeable about the problem domain: Yes. Accept the library: Reluctantly, the answer is no. He encourages the maintainer to consider addressing the issues I raised here, in which case I am ready to change my opinion. 1) Joaquín’s answer: * Instantiating a flyweight<T> will always create a temporary T (and hopefully just one when we get rvalue refs and variadic templates). The purpose of the library is *not* to avoid constructing expensive objects, it is to reduce memory consumption through object sharing. Collateral benefits include increased performance in object passing around. * GoF introduces a key type K into the pattern that is used to retrieve the actual values of T. So, we have a one-to-one relation KT, i.e. there exists a stateless function f of the form “T f(const K&)”. My analysis led me to conclude that the right approach is to assume that K==T. * Joaquín will investigate the potencial of the LookupFactory (factories that, additionally to the insert memfun, provide a find memfun) pattern, described at http://lists.boost.org/Archives/boost/2008/01/132798.php * I decided to keep "factory" because this component is obviously * related to the element of the same name in GoF and oher descriptions * of the pattern. * I’ll refine the reference section to make it easier write custom policies. 2) Alberto’s answer: I have another case in an project I am working on: in a 3D application, I have heavyweight 3D mesh objects that might be shared among several actors. The key of a 3D mesh is just its filename. I don't want to load an entire mesh into memory just to find out that I have it already. 3) Joaquín proposes the keyed_flyweight: struct character { character(char c):c(c){} char c; }; int main() { // fw_t objects are constructed from chars // but are convertible // to character. typedef keyed_flyweight<char,character> fw_t; // creates an internal character('a') fw_t x1('a'); // same shared value as x1, zero temporary character's fw_t x2('a'); // creates an internal character('b') fw_t x3('b'); } 4) Alberto proposes unifying keyed and non-keyd with just one flyweight class template: * we have two types: key_type for keys and value_type for values. The two types can be coincident (non-keyed proposal) * the constructor of flyweight semantically takes keys, not values * keys (not values) are fed as-is to the factory insert() method: it's up to the factory to determine whether the key is already present and if it's not present to construct the corresponding value. * the insert() method returns a handle * the factory provides a way to extract values from handles * The rest of the design would more or less stays exactly the same. 5) Joaquín’s answer to Alberto’s unified flyweight: I'd rather factories remained dumber so that all this intelligence is implemented in the core because: * STL associative containers are either set-like * (key_type=value_type) or map-like (T != value_type != key_type, because T == mapped_type). * The container would have to deal with a more general notion of key extraction. Boost.MultiIndex can do that, but I don't want to tie flyweight to that lib. Review manager note: The discussion went a bit further but the essence is that Joaquín has proposed alternatives and is ready to further discuss the issue because flyweight won’t be ready until Boost 1.36. I encourage Joaquín, Alberto and other contributors to discuss the issue in the future again. ------------------------- *John Torjo’s review* ------------------------- Design: Ok. Implementation: Ok. http://svn.boost.org/svn/boost/sandbox/flyweight/libs/flyweight/doc/tutoria… I think there could be a simpler way to do this: http://www.entropygames.net/globals.htm Documentation: Very nice Usefulness: Very useful. Used the library: No. Effort: 1.5h Knowledgeable about the problem domain: Yes Accept the library: Yes. ------------------------- *Markus Werle's review* ------------------------- Design: Not reviewed Implementation: Not reviewed Documentation: Good Usefulness: Yes Used the library: No Effort: Moderate Knowledgeable about the problem domain: No Accept the library: Yes ------------------------- *Kevin Sopp’s review* ------------------------- Design: Good. A way to get usage statistics about the flyweights would be nice (Joaquín agrees) Implementation: Good Documentation: Good Usefulness: Good Used the library: Yes Effort: Moderate Knowledgeable about the problem domain: Yes Accept the library: Yes Other accepted suggestions coming from non-review posts: Add assertions to catch static variables destruction ordering problems with flyweight. The refcounted tracking policiy can detect such illegal situations (an entry is destroyed with a refcount!=0). -------------------------- End of summary -------------------------- Ion Gaztañaga - Review Manager -

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Regex Library+ Urgent
by Srinivas Chamarthi 17 Feb '08

17 Feb '08

HI, I have built regex library with stlport using the following command nmake -fvc8-stlport.mak ( I copied vc71-stlport.mak to vc8-stlport and updated vc71 to vc80). It created *boost_regex-vc80-mt-gdp-1_34_1.lib *and dll files. I have defined the two variables in my application in the same order. #define #define __STL_DEBUG #define BOOST_REGEX_DYN_LINK Iam getting the following errors. can any 1 help me ? I am not able to proceed further with my application. I am stuck for last four days. I have seen some posts on this but not able to find the solution. I have defined the boost regex lib path properly. Appreciate your help Error 5 error LNK2019: unresolved external symbol "public: bool __thiscall boost::re_detail::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::match(void)" (?match@?$perl_matcher@PBDV?$allocator@U?$sub_match@ PBD@boost@@@stlp_std@@U?$regex_traits@DV?$w32_regex_traits@D@boost @@@boost@@@re_detail@boost@@QAE_NXZ) referenced in function "bool __cdecl boost::regex_match<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (??$regex_match@ PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@DU?$regex_traits@DV ?$w32_regex_traits@D@boost@@@boost@@@boost@@YA_NPBD0AAV?$match_results@PBDV ?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@0@ABV?$basic_regex@ DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@0@W4_match_flags@ regex_constants@0@@Z) ExprEvaluator.obj Error 6 error LNK2019: unresolved external symbol "private: void __thiscall boost::re_detail::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::construct_init(class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (?construct_init@?$perl_matcher@PBDV?$allocator@U?$sub_match@PBD@boost @@@stlp_std@@U?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@ re_detail@boost@@AAEXABV?$basic_regex@DU?$regex_traits@ DV?$w32_regex_traits@D@boost@@@boost@@@3@W4_match_flags@regex_constants@3@@Z) referenced in function "public: __thiscall boost::re_detail::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags,char const *)" (??0?$perl_matcher@ PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@U?$regex_traits@DV ?$w32_regex_traits@D@boost@@@boost@@@re_detail@boost@@QAE@PBD0AAV ?$match_results@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@2@ABV ?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@2@W4 _match_flags@regex_constants@2@0@Z) ExprEvaluator.obj

2 2

getline from boost::iostream::filtering_streambuf
by Holger Bast 17 Feb '08

17 Feb '08

I want to read line by line from a gzipped document. I first do: std::ifstream file(fileName.c_str()); boost::iostreams::filtering_streambuf<boost::iostreams::input> in; in.push(boost::iostreams::gzip_decompressor()); in.push(documentFile); However, then the obvious: string line; while(std::getline(in, line)) { ... } does not compile. Is there really no getline for filtering_streambuf? If not, what is the best way to write one? I tried reading character by character using boost::iostream::get(in) but that looks terribly inefficient to me, and is not nice code. Thanks for your help, Holger

2 6

Support for the Logic paradigm in C++ (with Castor)
by Naik, Roshan 16 Feb '08

16 Feb '08

This library (Castor) may be of interest to the "paradigm redefining" Boost community also ... -Roshan Naik ------------------------------------------------------------ Castor is a pure C++ Library that introduces the Logic paradigm (LP) into C++. Although LP has been well explored in Computer science, it remains under utilized in main stream software development due to lack of support in popular programming languages. Among the few languages that do support it, Prolog is perhaps the most commonly known. Instead of attempting to embed a Logic interpreter or other heavy weight engine into C++, Castor integrates LP using a few simple library primitives. This unique approach allows a natural and deep integration of declarative code into the language, and also provides the flexibility of combining Logic with other paradigms natively supported by C++ such as OOP, generics etc. STL concepts like iterators ,containers and streams can also be used in declarative code. Castor is an open source library distributed under the MIT license (http://www.opensource.org/licenses/mit-license.php) It is relatively small (under 5k LOC) and can be downloaded for free from http://www.mpprogramming.com For an introductory tutorial on LP and understanding its use in C++ refer to http://www.mpprogramming.om/resources/CastorTutorial.pdf Feedback, comments and contributions are welcome.

6 9

Can not compile 'adj_list_ra_edgelist.cpp'
by yi zhang 16 Feb '08

16 Feb '08

Hi, everyone 'adj_list_ra_edgelist.cpp' is a simple example of bgl, but I can not compile it with gcc 3.4.4 on cygwin/windows xp. Following are the codes: #include <boost/config.hpp> > #include <iostream> > #include <boost/graph/adjacency_list.hpp> > > int > main() > { > using namespace boost; > typedef adjacency_list<vecS, vecS, bidirectionalS, no_property, > property<int, edge_weight_t, property<int, edge_index_t> >, > no_property, vecS> Graph; > > const std::size_t n = 3; > typedef std::pair<std::size_t, std::size_t> E; > E edge_array[] = { E(0,1), E(0,2), E(0,1) }; > const std::size_t m = sizeof(edge_array) / sizeof(E); > Graph g(edge_array, edge_array + m, n); > for (std::size_t i = 0; i < m; ++i) > std::cout << edges(g).first[i] << " "; > std::cout << std::endl; > > return 0; > } The error is located in the line 28, i.e. edges(g).first[i]. I think edges(g).first has the type of adjacency_list::edge_iterator. But how can I understand 'edges(g).first[i]'? Thanks, Timothy Zhang

1 0

Pointers as graph vertex property
by Christian Sturz 15 Feb '08

15 Feb '08

Hi, I've a question about Boost Library Graphs. My Boost Graph is defined as: typedef boost::adjacency_list< boost::vecS, boost::vecS, boost::directedS, boost::property< boost::graph_name_t, std::string >, boost::property< boost::vertex_index_t, ClassA* > > Boost_Graph; So, I want to have a pointer to an entity of class ClassA as vertex property "vertex_index". However, when I try to access this property via a property map boost::property_map< Boost_Graph, boost::vertex_index_t >::type vertexNameMap = get( boost::vertex_index, g ); with vertexNameMap[v] (where v is Vertex_Type) the compiler tells me that the property is not of type 'ClassA*' (as I would expect) but of type 'size_t'. Why? I thought that for the definition of boost::property< boost::vertex_index_t, ClassA* > ClassA* is the template value and defines the type of the property "vertex_index". Any ideas how I can manage it to store pointers as vertex property? Regards, Christian -- Psst! Geheimtipp: Online Games kostenlos spielen bei den GMX Free Games! http://games.entertainment.web.de/de/entertainment/games/free

2 2

boost.xpressive - unicode supported?
by Amit 15 Feb '08

15 Feb '08

Hi, I am wondering whether Xpressive supports Unicode completely, as Regex does through ICU? I found out about Xpressive only recently, and it being header only is obviously a big plus; but my app is all about i18n, and makes use of regex patterns with character category predicates (e.g. [[:P*:]]). I read the docs for Xpressive - while it does claim to support Unicode, they have not provided a list of valid patterns, and unless they have code charts as part of headers, I don't see how they can provide full Unicode support with depending on ICU or something... Any clarification would be extremely helpful. Thanks Amit

2 1

[utility] question about enable_if
by Christian Henning 15 Feb '08

15 Feb '08

Hi there, I'm having a problem with using enable_if. For the sake of simplicity I have created the following test code which compiles fine. #include <string> #include <boost/mpl/and.hpp> #include <boost/utility/enable_if.hpp> using namespace std; using namespace boost; struct reader {}; template< typename String > struct is_string : public mpl::false_ {}; template<> struct is_string<std::string> : public mpl::true_ {}; template< typename Device > struct is_device : public mpl::false_ {}; template<> struct is_device<reader> : public mpl::true_ {}; template< typename String> struct enable_if_helper { typedef typename enable_if< typename is_string< String >::type >::type type; }; template<typename Device > void foo( typename enable_if< typename is_device<Device>::type >::type* ptr = 0 ) {} template<typename String> void foo( typename enable_if< typename is_string<String>::type >::type* ptr = 0 ) { foo<reader>(); } int main(int argc, _TCHAR* argv[]) { foo<std::string>(); return 0; } If I changed the string foo() interface to use the enable_if_helper the code doesn't compile anymore. Why is that? I've changed the foo ( with the string template parameter ) to the following: template<typename String> void foo( typename enable_if_helper< String >::type* ptr = 0 ) { foo<reader>(); } Anyone can help me out here? I'm using Visual Studio 8. Thanks, Christian

2 2

[xpressive] Pattern problems (newbie)
by ope 14 Feb '08

14 Feb '08

Hi, I'try to build a regex for an ibis file, the line I'm interested looks like: [IBIS Ver] 3.2 | Used for template variations" where '|' is an optional comment identifier with the (therefore optional) comments follows. I'm interested in the version self: "3.2" to create a parser using a factory. Using egrep '^\[IBIS Ver]' success. From docs I tested the dynamic regex $ perl -p -e '(\\w+) (\\w+)!' "Hello World" which fails (syntax error at -e line 1, near "+) ") The regex are perl syntax, isn't? What is the regex for my IBIS Ver identifier? Thanks, Olaf

2 1

[iostreams] Question about correct opened file
by ope 14 Feb '08

14 Feb '08

Hi, I've the following code: namespace io = boost::iostreams; bool foo::open( const std::string& file ) { io::filtering_istream is; is.push( my_line_filter() ); is.push( io::file_source( file ) ); // ??? how to check success do { std::string line; std::getline(is, line); std::cout << line << std::endl; } while (!is.eof()); return true; } Well, how can I check that the file is opened correct/the stream is valid? is_open() and good() seems not supported? Or I'm wrong? Giving a wrong name does nothings. Thanks, Olaf

2 2

Linker Errors
by Srinivas Chamarthi 14 Feb '08

14 Feb '08

Hi All, - I have built STL5.1.4 with VC8. - boost against stlport with the following command -> make - fvc8-stlport.mak *It created all the necessary libs and dlls. * I have defined the following in my application. *#define __STL_DEBUG #define BOOST_REGEX_DYN_LINK * But I am still getting the following linker errors. Any one can help me with these errors ? *Appreciate your help in advance* Error 3 error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > >::~match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > >(void)" (__imp_??1?$match_results@ PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@boost@@QAE@XZ) referenced in function "public: static bool __cdecl ExprEvaluator::doesStringMatchRegExpr(char const *,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >)" (?doesStringMatchRegExpr@ExprEvaluator@@ SA_NPBDV?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@boost@@@Z) ExprEvaluator.obj Error 4 error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > >::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > >(class stlp_std::allocator<struct boost::sub_match<char const *> > const &)" (__imp_??0?$match_results@ PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@boost@@QAE@ABV ?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@Z) referenced in function "public: static bool __cdecl ExprEvaluator::doesStringMatchRegExpr(char const *,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >)" (?doesStringMatchRegExpr@ExprEvaluator@@ SA_NPBDV?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@boost@@@Z) ExprEvaluator.obj Error 5 error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::re_detail::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::~perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(void)" (__imp_??1?$perl_matcher@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@ U?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@re_detail@boost@@ QAE@XZ) referenced in function "bool __cdecl boost::regex_match<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (??$regex_match@PBDV?$allocator@U ?$sub_match@PBD@boost@@@stlp_std@@DU?$regex_traits@DV?$w32_regex_traits@ D@boost@@@boost@@@boost@@YA_NPBD0AAV?$match_results@PBDV?$allocator@ U?$sub_match@PBD@boost@@@stlp_std@@@0@ABV?$basic_regex@DU?$regex_traits@DV ?$w32_regex_traits@D@boost@@@boost@@@0@W4_match_flags@regex_constants@0@@Z) ExprEvaluator.obj Error 6 error LNK2019: unresolved external symbol "__declspec(dllimport) public: bool __thiscall boost::re_detail::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::match(void)" (__imp_?match@?$perl_matcher@PBDV?$allocator@U?$sub_match@PBD@boost @@@stlp_std@@U?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@ re_detail@boost@@QAE_NXZ) referenced in function "bool __cdecl boost::regex_match<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (??$regex_match@ PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@DU?$regex_traits@DV ?$w32_regex_traits@D@boost@@@boost@@@boost@@YA_NPBD0AAV?$match_results@PBDV ?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@0@ABV?$basic_regex@ DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@0@W4_match_flags@ regex_constants@0@@Z) ExprEvaluator.obj Error 7 error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::re_detail::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags,char const *)" (__imp_??0?$perl_matcher@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@ U?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@re_detail@boost@@ QAE@PBD0AAV?$match_results@PBDV?$allocator@U?$sub_match@PBD@boost @@@stlp_std@@@2@ABV?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@ D@boost@@@boost@@@2@W4_match_flags@regex_constants@2@0@Z) referenced in function "bool __cdecl boost::regex_match<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (??$regex_match@PBDV?$allocator@U ?$sub_match@PBD@boost@@@stlp_std@@DU?$regex_traits@DV?$w32_regex_traits@ D@boost@@@boost@@@boost@@YA_NPBD0AAV?$match_results@PBDV?$allocator@ U?$sub_match@PBD@boost@@@stlp_std@@@0@ABV?$basic_regex@DU?$regex_traits@DV ?$w32_regex_traits@D@boost@@@boost@@@0@W4_match_flags@regex_constants@0@@Z) ExprEvaluator.obj thanks & regards Srinivas Chamarthi

1 0

DebuggerVisualizers update
by Filip Konvička 14 Feb '08

14 Feb '08

Hi Boost, I've just updated the Debugger Visualizers wiki at http://svn.boost.org/trac/boost/wiki/DebuggerVisualizers The main change is that the visualizer files are now all available at https://svn.boost.org/svn/boost/sandbox/boost_docs/subprojects/DebuggerVisu… and, thanks to the effort and interest of Jon Fogh, there is a new visualizer for boost::interprocess::offset_ptr. Enjoy, Filip

1 0

Serialization hash_map
by christophe loustaunau 14 Feb '08

14 Feb '08

Hello, Recently I have used Boost for serialization. Unfortunatly it doesn't work with hash_map. I work with Visual 8, and Visual 8 used the dinkumware version of std lib. In order to make things working I have modified three files of boost : in the folder config/stdlib : dinkumware.hpp : BOOST_HAS_HASH is not defined.(why ?). in the folder serialization : hash_collections_load_imp.hpp : In this file I have made these changes : template<class Archive, class Container, class InputFunction> inline void load_hash_collection(Archive & ar, Container &s) { s.clear(); // retrieve number of elements unsigned int count; unsigned int item_version(0); // unsigned int bucket_count;; ar >> BOOST_SERIALIZATION_NVP(count); // if(3 < ar.get_library_version()){ // ar >> BOOST_SERIALIZATION_NVP(bucket_count); // ar >> BOOST_SERIALIZATION_NVP(item_version); // } // #if ! defined(__MWERKS__) // s.resize(bucket_count); // #endif InputFunction ifunc; while(count-- > 0){ ifunc(ar, s, item_version); } } } // namespace stl } // namespace serialization } // namespace boost hash_collections_save_imp.hpp : In this file I have made these changes : template<class Archive, class Container> inline void save_hash_collection(Archive & ar, const Container &s) { // record number of elements unsigned int count = s.size(); ar << BOOST_SERIALIZATION_NVP(count); // make sure the target type is registered so we can retrieve // the version when we load // if(3 < ar.get_library_version()){ // const unsigned int bucket_count = s.bucket_count(); // ar << BOOST_SERIALIZATION_NVP(bucket_count); // const unsigned int item_version = version<BOOST_DEDUCED_TYPENAME Container::value_type>::value; // ar << BOOST_SERIALIZATION_NVP(item_version); // } BOOST_DEDUCED_TYPENAME Container::const_iterator it = s.begin(); while(count-- > 0){ // note borland emits a no-op without the explicit namespace boost::serialization::save_construct_data_adl( ar, &(*it), boost::serialization::version< BOOST_DEDUCED_TYPENAME Container::value_type >::value ); ar << boost::serialization::make_nvp("item", *it++); } } } // namespace stl } // namespace serialization } // namespace boost With this changes Serialization of hash_map works well. Maybe you could make a : #if (!defined dinkumware ) ..... # endif In theses two files in order to make the serialization of hash_map with dinkumware working. Thanks for your time and your so good library ! -- Christophe Loustaunau.

1 0

tuple<...involves template par...>
by e r 14 Feb '08

14 Feb '08

Hi, I have the following: template<typename T> class A: public std::unary_function<const boost::tuple<double,const T&>&, void>{ public: typedef typename std::unary_function<const boost::tuple<double,const T&>&, void> parent_type; typedef typename parent_type::argument_type argument_type; void operator()(argument_type t)const{ t.get<0>(); //error: expected primary-expression before ')' token t.get<1>(); //error: expected primary-expression before ')' token }; }; Similar code without the template (i.e. fix say T = double) works fine. Anybody, pls help. Thanks.

6 6

[lambda] Compilation problem because of EXCEPTION
by Knut Hunstad 13 Feb '08

13 Feb '08

Hi! I haven't used boost much yet, but have been looking into lambda expressions. I am working within a huge system, where one of the include files has a macro definition for EXCEPTION. Which is also used as an enum value in boost/lambda/detail/arity_code.hpp (within namespace boost::lambda): enum { NONE = 0x00, // Notice we are using bits as flags here. FIRST = 0x01, SECOND = 0x02, THIRD = 0x04, EXCEPTION = 0x08, RETHROW = 0x10}; Using common names such as this in a general library seems a bit risky to me. Any header before "boost/lambda.hpp" which defines macros for any of these enum values, will cause trouble. I don't have insight enough in boost to suggest the correct solution (or to conclude that I have to fix the problem in my own code and let boost::lambda remain unchanged :-). For me right now the fix was simply replacing the (4) occurences of this EXCEPTION with LAMBDAEXCEPTION in the boost files. Where do I go to put this up as a fix-suggestion? I would like to avoid having to remember this replace every time I upgrade boost... Best regards, Knut Hunstad Vianova Systems AS Norway

2 1

[Interprocess] gcc 3.2 support?
by Matt Wharton 13 Feb '08

13 Feb '08

Greetings, So, I appear to have hit a stumbling block with GCC 3.2 and Boost.Interprocess (the latest from the release branch which I _believe_ to be the latest 1.35). Specifically, when I try to build the following code, I get numerous compilation errors (they appear to be template related). ---------------------- #include <boost/interprocess/managed_shared_memory.hpp> int main() { return 0; } ------------------------- Is there any way to get this work under my older GCC version or am I out of luck? Thanks in advance! -Matt

3 2

Re: [Boost-users] XML Serialization and the Generation of a W3C Schema
by Joseph Fradley 13 Feb '08

13 Feb '08

Robert, Fair enough, I'll see if I can make something useful in the amount of time I have. Joe > I don't. I guess its up to you. > > Robert Ramey > > Joseph Fradley wrote: > > Hello, > > > > I've seen a few postings on how a XSD generating archiver would be > > written and a posting for a google code project on it. But I can't > > seem to find any implementations. > > > > Does anybody know of any implementations? > > > > Joe >

2 1