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[gsoc] boost.heap update
by Tim Blechmann 29 Jul '10

29 Jul '10

hi all, i've uploaded a new snapshot of boost.heap. it includes some of the proposed changes and i have also added a benchmark sections. during the final time for the gsoc, i'd like to get the library ready for a review ... therefore, i uploaded a new snapshot [1] and an updated documentation [2]. feedback welcome ... cheers, tim [1] http://tim.klingt.org/code/attachments/download/31/boost_heap_280710.tar.gz [2] http://tim.klingt.org/boost_heap -- tim(a)klingt.org http://tim.klingt.org Cheat your landlord if you can and must, but do not try to shortchange the Muse. It cannot be done. You can't fake quality any more than you can fake a good meal. William S. Burroughs

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Phoenix3 port to proto complete
by Thomas Heller 29 Jul '10

29 Jul '10

Ladies and Gentlemen, I proudly announce that the port of phoenix3 is completed! All testcases pass! (some with minor modifications) So, What is next? Here is my proposed schedule: - fix some minor issues - improve boost.bind compatibility: make all boost.bind testcases pass - implement all boost.lambda testcases and make them pass, as far as it is reasonable - add support for C++0x lambdas - make interoperability testcases for std::function, boost::function - adapt the documentation - clean up code (some parts are a little messy as of now) - improve compile time Did I miss something? This is a very tight schedule, I may not be able to finish all points during the GSoC period. Any help will be appreciated. Additionally a review of the current code is highly appreciated to point out some defects that might exist. The code can be checked out at: https://svn.boost.org/svn/boost/sandbox/SOC/2010/phoenix3 I will be happy to answer your questions! Additionally I would like to thank Joel de Guzman and Eric Niebler for their great assistance and initial designs! Best Regards, Thomas Heller

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review request for boost.context
by Oliver Kowalke 29 Jul '10

29 Jul '10

Hello John, hello Ronald, could you add boost.context to the review queue please. boost.context allows to switch between execution contexts. The state of the context which will be left is saved and maybe resumed later. It is a kind of POSIX ucontext (fallback on POSIX platforms for boost.context) but provides assembler for some platforms (faster and some platforms doesn't implement POSIX ucontext because it is deprecaded -> ARM). thanks an best regards, Oliver

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[Boost] [Thread] Query: Stack Size
by Alapkumar Sinha 29 Jul '10

29 Jul '10

Hi, How can I change the default stack size for each new thread being created? Secondly is there a mechanism to set the stack size while creation? I read somewhere that the default stack size is 8MB which is heavy for my application. Please suggest. Regards, Alap ________________________________ This Email may contain confidential or privileged information for the intended recipient (s) If you are not the intended recipient, please do not use or disseminate the information, notify the sender and delete it from your system. ______________________________________________________________________

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[Interprocess] Query on Message queue
by Alapkumar Sinha 29 Jul '10

29 Jul '10

Hi, I have a requirement to have message type based receiving functionality, like the one provided by linux ipc "ssize_t msgrcv(int msqid, struct msgbuf *msgp, size_t msgsz, long msgtyp, int msgflg); " But the messagequeue implementation in boost only allows to set a priority of the message and does not provide a mechanism to wait on a messagequeue based on message type. Can someone tell me if there is a way out to get the above functionalities through boost as well. Regards, Alap ________________________________ This Email may contain confidential or privileged information for the intended recipient (s) If you are not the intended recipient, please do not use or disseminate the information, notify the sender and delete it from your system. ______________________________________________________________________

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[serialization] Padding for base64 dataflow iterators ?
by Timothy Madden 29 Jul '10

29 Jul '10

Hello Could the documentation page for dataflow iterators in the serialization library please state that: 1. using base64 iterators will /not/ add the padding '=' characters in the encoded data, that are present in the canonical encoding in RFC4648 (The Base16, Base32, and Base64 Data Encodings) ? 2. binary string to be encoded should be null-terminated, or the iterators will not pad the input stream of bits with 0s to reach a multiple of 6 bits, but rather use whatever bits follow after the last encoded byte in memory ? Just so the user knows she either has to ensure padding, or otherwise she should not expect the result to exactly follow the RFC, and the result might not be suitable for data interchange between applications, etc ... Or maybe the examples could be changed to include padding, which would be even better ... :) Thank you, Timothy Madden

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[placeholders]
by Andrzej Krzemienski 29 Jul '10

29 Jul '10

Hi, I have a problem with Boost.Bind placeholders. Namely, once I include the <boost/bind.hpp> it automatically brings placeholders _1, _2, .. into scope and I cannot use placeholders from other libraries like Spirit.Qi any more. I.e. I can but I need to qualify them like qi::_1, qi::_2, which is annoying. I include <boost/bind.hpp> in a precompiled header, so I have no option of not including it. Boost.Bind could define them in namespace boost::bind_placeholders and we could control their visibility with namespace using directive. This is what Spirit does, and it is cute. I guess I would not be able to convince anyone that Bind should do the same. But would it be possible to define placeholders _1, _2, ... as something more generic in Boost, unrelated to any particular library? Then boost::bind, would treat it as its own placeholders, Spirit semantic actions would treat them as its own placeholders, but they would be exactly same placeholders. Regards, &rzej

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[interprocess] cmake files on trunk
by Eric Niebler 28 Jul '10

28 Jul '10

Looks like some CMake build files were inadvertently committed to boost trunk (changeset https://svn.boost.org/trac/boost/changeset/64331) I say "inadvertent" because there's no way these files can work in isolation, considering that all other CMake support has been removed from boost trunk. Ion, can you please remove these files? Thanks, -- Eric Niebler BoostPro Computing http://www.boostpro.com

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thread_safe_ptr class interest request
by Philippe Vaucher 28 Jul '10

28 Jul '10

Hello, I've made a thread_safe_ptr class available at http://codepad.org/PxDEGaFm The idea is to use it like so: std::string data = "Hello world;"; thread_safe_ptr<std::string> data_ptr(&data); void thread1() { data_ptr->resize(3); } void thread2() { *data_ptr = "yeah"; } boost::thread t1(&thread1); boost::thread t2(&thread1); t1.join(); t2.join(); Do you see an obvious show-stopper for me not to continue developping this class? What's still to be done is worry about ownership of objects, my idea is to eventually somewhat model it after boost::shared_ptr that way it's easier to pass those around. When I'll be satisfied with the result, my plan is to "boostify" it (namespaces, license etc) and maybe propose it for inclusion in the smart pointer library. What are your thoughts? Philippe

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[serialization] patching 1.43 for the version numbering issue
by Ryan Gallagher 28 Jul '10

28 Jul '10

Hi Robert, As we were discussing the other day, I'd like to just patch my 1.43 release to fix the serialization library versioning issue so that my archives created with it won't need to have the utility run on them for 1.44+ to understand them. I just want to verify with you that changing the version number in serialization/src/basic_archive.cpp is all that's needed. In your recent trunk change you increased the version for 1.44 to '8': https://svn.boost.org/trac/boost/changeset/64157 However, the 1.43 source seems to have version '7' already. I must be missing something as I don't see how binary archived were using library version '6' for 1.42/43. Thanks, -Ryan

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SGI rope in boost?
by Yakov Galka 28 Jul '10

28 Jul '10

Hello all, I can't use SGI's STL for several reasons: * It's incompatible with the standard library implementation shipped with my compiler (MVS). * Extracting only ropes is a headache, there are too much dependencies. * Unacceptable license. Were there any discussions about implementing ropes in boost? Yakov

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Fisher Exact test in boost ?
by Jean-Baptiste Cazier 28 Jul '10

28 Jul '10

Dear all, I am brand new to this mailing list so I apologize in advance for the naivety of my request. I am looking for an implementation of the Fisher exact test in C/C++, and was somehow hoping to find one in boost. I have looked at the documentation of boost and and found many statistical tools, but not the one I am looking for. The closest I got was a discussion in the mailing archive in 2008 on the use of the hypergeometric distribution to perform such implementation Was any progress made since then ? Could I now get the cdf, pmf and sf from an hypergeometric distribution ? or even better a Fisher exact test directly ? Any help will be welcome Thanks Cheers ! Jean-Baptiste

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Re: [boost] [GIL] bits64
by fabien.castan＠free.fr 28 Jul '10

28 Jul '10

> I have been promoting the idea of people contributing any new functionality > of GIL that they find useful by creating a GIL extension that is not > originally in boost. This allows for an opportunity for people to try their > code, flesh out some bugs, suggest changes to the design, etc. We can also > use this as a mechanism to see how popular certain functionality is and use > that to decide which functionality will make it into boost. That way, by the > time it is proposed for inclusion into boost, the code will be more solid. Yes, I have seen it, I use it, and hope to propose new things one day. But adding typedefs is not adding new functionalities. It's the normal usage of the library. If there is a bug here, it's a bug in gil itself not in the added code... So I define it in my code and use it without problem. Maybe we can add those typedefs at least in gil extensions ? If you want I can send you the code.

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[context] user-context switching
by Oliver Kowalke 27 Jul '10

27 Jul '10

I've moved the context switching code from boost.fiber into a new lib - boost.context (uploaded to boost vault). The lib contains assembler for some platforms: i386, x86_64 and arm (aapcs-linux only). It could be used for code implementing cooperative scheduling (such as boost.coroutine and boost.fiber). Oliver

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[gsoc][RFC] Pointer Plus Bits
by Brian Bartman 27 Jul '10

27 Jul '10

Hello, I previously sent out an email to the list about a pointer plus bits like data structure and received some feedback about a pointer plus bits data structure. After taking into consideration all of the different points of view, comments and concerns voiced by the Boost community I have implemented an extension to my bitfield_tuple which allows the user to easily store parts of a pointer and use the extra bits for storage. Here is a basic overview of the bitfield_tuple: Its a tuple like data structure which stores bitfields instead of whole types inside of single tuple. This allows the user to skirt packing limitations of structs and classes in C++ and create bitfields over the storage type of their choice OR leave that decision up to the data structure (the behavior for selecting the storage type is to select the smallest possible unsigned integral type which will hold the all of the bitfields). example of basic bitfield_tuple declaration. #include<boost/integer/bitfield_tuple.hpp> struct red; struct green; struct blue; using namespace boost; using namespace boost::bitfields; typedef bitfield_tuple< member<unsigned char, red, 5>, member<char, green, 6>, member<unsigned int, blue,5> > rgb565_t; The bitfield_tuple takes ordered named template parameters (In the case of the storage type order is ignored. IE no matter where you put the storage< type > template the ending result will be the same). the bitfield_tuple supports the following template named template parameters (all of the templates which follow are located within the boost::bitfields namespace): bit_align< std::size_t> -> increases the offset of the next field to an offset which is divisible by the supplied value unless the current index is divisible by the supplied value then there is no increase. filler<std::size_t> -> bits to be skipped. member<typename, typename, std::size_t> -> this is a basic bitfield parameters it takes are the type the bitfield is to return, a naming type and the width of a bitfield flag<typename> -> boolean version of member. storage<typename> -> uses the supplied type for internal storage. pointer<typename, typename, typename> -> NEW described below. Pointer Member Information: The pointer member takes three template parameters. 1) The type you would like to make a pointer to. 2) The name which can be used (instead of an index, index is also still available to use) to access the pointer. 3) This is an integral_constant or integral_constant like type which is used to make a mask over the value bits of the pointer. This has a default value to leave the last two bits open. You can use leading or ending bits of the pointer for storage by supplying a different mask. Reasoning behind allowing for leading storage bits. There are some systems which do low address allocations and then store values within the higher part of the address. While this is much more rare then the use case of stuffing two bits inside of the end of a pointer I felt that it would be best to provide a way to actually do this. Reasoning behind restricting the mask to an integral_constant or integral_constant like type. The intent for this is to associate a non deduced type with the mask itself, however if people feel better simply using hex to specify the mask I could change the behavior to do that. There are mask creation utilities which can be used to create the mask from a higher level the simply supplying hex. Here are some examples of how to declare a bitfield_tuple with a pointer member: #include <boost/integer/bitfield_tuple.hpp> #include <boost/assert.hpp> using namespace boost; using namespace boost::bitfields; struct ptr; struct color; struct i1; struct i2; typedef bitfield_tuple< pointer<int, ptr> > ptr_1; typedef bitfield_tuple< pointer<int, ptr>, flag<b1>, flag<b2> > ptr_plus_two_bools; typedef bitfield_tuple< pointer<int, ptr>, member<unsigned int,color,2> > ptr_plus_two_bit_color; int main() { ptr_1 p1; int i = 10; p1.get<0>() = &i; BOOST_ASSERT(*p1.get<ptr>() == 10); ptr_plus_two_bools p2; p2.get<ptr>() = &i; ptr.get<b1>() = true; ptr.get<2>() = false; ptr_plus_two_bit_color p3; p3.get<ptr>() = &i; p3.get<color>() = 3; return 0; } The pointer does NOT have to be the first parameter of the bitfield tuple one can simply place things in front of the the pointer and the value mask of the pointer will not be affected. The only thing which is different when this is done is the offset of the pointer within the bitfield_tuples storage, this only changes the location of the bitfield where the pointer is actually being stored. That being said you will always receive the value bits of the pointer in the exact same way they were taken from inside the pointer. -- thanks, Brian Bartman

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Question about boost license
by Marc Elias 27 Jul '10

27 Jul '10

Hello, Allow me to introduce myself, my name is Marc and I would like to use the boost libraries to perform some work on a software with commercial profit. I have some questions about Boost License Policy I would like to know. As I can read in your webpage, most of the Boost libraries are under a single license that allows me to use the libraries for commercial purposes following the instructions you provide in the webpage. You also inform in the webpage that some libraries are under their own licenses. I would like to know, if it's possible, which libraries are under particular licenses and which are these specific licenses. Is it possible to have this information? Thanks a lot for your help. MARC _________________________________________________________________ Accede a tu Hotmail en un solo clic ¡Descárgate Internet Explorer 8 y empieza a disfrutar de todas las ventajas! http://www.ayudartepodria.com/

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Review request: XInt
by Chad Nelson 26 Jul '10

26 Jul '10

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I am officially requesting a formal review for the Extended Integer library (a arbitrary-length integer math library). The final review version is now available in the sandbox (at <https://svn.boost.org/svn/boost/sandbox/xint>) and the Vault (at <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=xint.z…>). Thanks to everyone who offered suggestions and comments. It's a lot better for them, and likely a lot more useful. Here's hoping for a positive and speedy review. :-) - -- Chad Nelson Oak Circle Software, Inc. * * * -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkw9BTYACgkQp9x9jeZ9/wQX+gCgi1N29anc96B6EX+pZ5rgrvyu d8wAnjfHyu5JQVMVu6BFQPtYExG3SbZR =25L3 -----END PGP SIGNATURE-----

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New name of bjam.exe
by Vladimir Prus 26 Jul '10

26 Jul '10

Boosters, I am sure that most of you got accustomed to typing "bjam" in console whenever you want to build things. This name is old, and derives from a tool named "jam", which is even older (around for maybe 20 years). However, this name is probably no longer good. First, having a single project be identified by both "Boost.Build" and "bjam" names proves inconveninent from "marketing" and conveninence standpoints, to the point where many users try to read documentation for Boost.Jam, don't find anything there, and become upset. Second, users get the idea that Boost.Build is somehow related to "Classic Jam", which is not true. For those reasons, Rene and I have decided that "bjam.exe" should go. We're thinking about naming the executable simply "build.exe", since no other build tool bothered to take it. Does anybody have comments, or better suggestions? Thanks, Volodya

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[1.44] Snapshot available
by Beman Dawes 26 Jul '10

26 Jul '10

The daily release snapshots are working fully again. That's important because the releases are based on the snapshots. See http://boost.cowic.de/rc/ --Beman

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Bugs in program_options library
by Jorge Lodos Vigil 26 Jul '10

26 Jul '10

Hi The function options_description::find_nothrow throws an exception when there are at least 2 exact matches. Since this function is in the public interface this could be considered a bug (it must not throw). Please note that this function is used several times within the implementation without try clauses. The exception thrown might be being used by callers of the method find, so you cannot just remove it. It is best to implement find and find_nothrow as follows: const option_description& options_description::find(const std::string& name, bool approx, bool long_ignore_case, bool short_ignore_case) const { shared_ptr<option_description> found; vector<string> approximate_matches; vector<string> full_matches; // We use linear search because matching specified option // name with the declared option name need to take care about // case sensitivity and trailing '*' and so we can't use simple map. for(unsigned i = 0; i < m_options.size(); ++i) { option_description::match_result r = m_options[i]->match(name, approx, long_ignore_case, short_ignore_case); if (r == option_description::no_match) continue; if (r == option_description::full_match) { full_matches.push_back(m_options[i]->key(name)); found = m_options[i]; } else { // FIXME: the use of 'key' here might not // be the best approach. approximate_matches.push_back(m_options[i]->key(name)); if (!found) found = m_options[i]; } } if (full_matches.size() > 1) boost::throw_exception( ambiguous_option(name, full_matches)); // If we have a full match, and an approximate match, // ignore approximate match instead of reporting error. // Say, if we have options "all" and "all-chroots", then // "--all" on the command line should select the first one, // without ambiguity. if (full_matches.empty() && approximate_matches.size() > 1) boost::throw_exception( ambiguous_option(name, approximate_matches)); if (!found) boost::throw_exception(unknown_option(name)); return *found; } const option_description* options_description::find_nothrow(const std::string& name, bool approx, bool long_ignore_case, bool short_ignore_case) const { try { const option_description& d = find(name, approx, long_ignore_case, short_ignore_case); return &d; } catch(const std::exception&) { return NULL; } } This modification uncovers a bug in function cmdline::finish_option (cmdline.cpp) where find_nothrow is being called assuming that no exception will be thrown. The first part of this function might be modified to: void cmdline::finish_option(option& opt, vector<string>& other_tokens, const vector<style_parser>& style_parsers) { if (opt.string_key.empty()) return; const option_description* xd; try { // First check that the option is valid, and get its description. xd = &m_desc->find(opt.string_key, is_style_active(allow_guessing), is_style_active(long_case_insensitive), is_style_active(short_case_insensitive)); } catch(const std::exception&) { if (m_allow_unregistered) { opt.unregistered = true; return; } throw; } const option_description& d = *xd; // Canonize the name opt.string_key = d.key(opt.string_key); ........ } Now it can throw the correct exception thrown by the find method. This is the only way callers could know the correct exception. It was apparently working before because find_nothrow was throwing exceptions not captured within cmdline::finish_option. You may chose to eliminate the xd variable altogether and initialize and use d within the try clause. What is important is to call find instead of find_nothrow. The following test would have detected these problems and the one solved in https://svn.boost.org/trac/boost/ticket/4159: // Multiple arguments test_case test_cases2[] = { {"--fname file --fname2 file2", s_success, "fname: file fname2: file2"}, {"--fnam file --fnam file2", s_ambiguous_option, ""}, {"--fnam file --fname2 file2", s_ambiguous_option, ""}, {"--fname2 file2 --fnam file", s_ambiguous_option, ""}, {0, 0, 0} }; test_cmdline("fname fname2", style, test_cases2); This test may be added at the end of the test_guessing function in cmdline_test.cpp. I have created the ticked 4469 (https://svn.boost.org/trac/boost/ticket/4469) with this information. Thank you. Best regards Jorge

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[chrono] [thread] boost.chrono changes to boost::condition_variables
by Morgan Henry 26 Jul '10

26 Jul '10

Hello, I've been exploring the boost.chrono candidate library as a basis for some fixes to boost::condition_variables::timed_wait(). I have some questions: 1) What is the current state of the chrono library, and its likely path into boost? 2) Are the chrono API changes to boost::condition_variables likely to be accepted into the boost.thread library in their current form? (i.e introduction of wait_for(), wait_until(), and the introduction of a new explicit dependency from boost/thread/condition_variables on chrono::time_point etc...) 3) Are there any other planned changes to boost::condition_variables::timed_wait to allow use of POSIX clocks other than CLOCK_REALTIME? My ultimate goal is to provide an implementation of boost::condition_variables that allows access to the POSIX clock CLOCK_MONOTONIC for use through boost::condition_variables::timed_wait(). Specifically, providing an implementation that uses pthread_condattr_setclock(&attr, CLOCK_MONOTONIC) at boost::condition_variables initialisation, and use of pthread_cond_timedwait(..., &t) with clock_gettime(CLOCK_MONOTONIC, &t) in boost::condition_variables::timed_wait() and friends This change would provide reasonable behaviour of boost::condition_variables::time_wait() in presence of ongoing changes to the system clock. boost.chrono contributes to this goal by providing a clock abstraction and accessors to the appropriate POSIX clocks through class monotonic_clock, class system_clock, etc... Further to this, changes to boost::condition_variable::timed_wait() and similar would be required to use clock_gettime(CLOCK_MONOTONIC, &t) rather than boost::get_system_time() for calculations when the monotonic_clock is specified. I'm currently considering whether to trust that the boost.chrono API changes to the boost::condition_variables API are robust, and likely to persist for the future. Or to propose alternative changes localised to boost::condition_variables that achieve the goals above without the strong dependency on boost.chrono. Thanks for any comments or information about the above. Morgan http://www.bbc.co.uk/ This e-mail (and any attachments) is confidential and may contain personal views which are not the views of the BBC unless specifically stated. If you have received it in error, please delete it from your system. Do not use, copy or disclose the information in any way nor act in reliance on it and notify the sender immediately. Please note that the BBC monitors e-mails sent or received. Further communication will signify your consent to this.

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Re: [boost] Phoenix3 port to proto complete
by Thomas Heller 26 Jul '10

26 Jul '10

Doug Gregor wrote: > On Fri, Jul 23, 2010 at 11:14 AM, Thomas Heller > <thom.heller(a)googlemail.com> wrote: >> Mathias Gaunard wrote: >> >>> On 23/07/10 14:18, Thomas Heller wrote: >>>> Ladies and Gentlemen, >>>> I proudly announce that the port of phoenix3 is completed! All >>>> testcases pass! (some with minor modifications) >>>> >>>> So, What is next? Here is my proposed schedule: >>>> - fix some minor issues >>>> - improve boost.bind compatibility: make all boost.bind testcases pass >>>> - implement all boost.lambda testcases and make them pass, as far as it >>>> is >>>> reasonable >>>> - add support for C++0x lambdas >>>> - make interoperability testcases for std::function, boost::function >>>> - adapt the documentation >>>> - clean up code (some parts are a little messy as of now) >>>> - improve compile time >>>> >>>> Did I miss something? >>> >>> I would quite like to know how Phoenix 3 compares to Phoenix 2 in terms >>> of compile speed, even if you haven't fully optimized it yet. >> >> Let me give you a small example of what situation we currently have: >> >> For this test i used the core/primitives_test.cpp test and g++ 4.5 >> >> Phoenix3 total compile time: 3.421s >> Phoenix3 preprocess time: 1.755s >> Phoenix3 compile time of preprocessed code: 1.835s >> >> Phoenix2 total compile time: 1.891s >> Phoenix2 preprocess time: 0.745s >> Phoenix2 compile time of preprocessed code: 1.106s >> >> comparing with clang: >> >> Phoenix3 total compile time: 3.901s >> Phoenix3 preprocess time: 2.738s > > Ouch! The Clang guys will be looking into this > preprocessor-performance issue to see if we can do better. Thanks for > reporting this! > > - Doug Thanks for looking into this! FYI, I was able to identify one bottleneck for the preprocessor. It was by including boost/fusion/include/vector.hpp. I instead included the different boost/fusion/container/vector/vectorN.hpp and was able to reduce compile-time by one second. New timings for the above test are: thomas@sunshine ~/programming/boost $ compile-time g++ -I. libs/phoenix/test/core/primitives_tests.cpp complete compile time: real 0m2.385s user 0m2.253s sys 0m0.120s preprocessing time: real 0m1.254s user 0m1.230s sys 0m0.017s compile time without preprocessing: real 0m1.234s user 0m1.157s sys 0m0.067s thomas@sunshine ~/programming/boost $ compile-time clang++ -I. libs/phoenix/test/core/primitives_tests.cpp complete compile time: real 0m2.709s user 0m2.337s sys 0m0.340s preprocessing time: real 0m1.765s user 0m1.417s sys 0m0.337s compile time without preprocessing: real 0m1.011s user 0m0.913s sys 0m0.080s

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boost-trunk compile failure gcc 4.4.3
by Gaetano Mendola 25 Jul '10

25 Jul '10

current trunk has a compilation failure, the following diff solves it Index: boost/optional/optional_io.hpp =================================================================== --- boost/optional/optional_io.hpp (revision 64315) +++ boost/optional/optional_io.hpp (working copy) @@ -74,12 +74,12 @@ else { if ( d != '-') - in.setstate( ios::failbit ); + in.setstate( std::ios::failbit ); d = in.get(); if ( d != '-') - in.setstate( ios::failbit ); + in.setstate( std::ios::failbit ); v = optional<T>() ; } Regards Gaetano mendola

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Property tree bug
by OvermindDL1 25 Jul '10

25 Jul '10

I am attempting to use a recent boost trunk due to updates I need, however propertytree has a build bug that has already been submitted a few days ago, what is the status of this? The fix is already in the bug ticket. https://svn.boost.org/trac/boost/ticket/4459

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Conflict with patent
by Francisco José Tapia 24 Jul '10

24 Jul '10

I am a teacher of programming in a Technical Professional Training School in Madrid ( Spain). I had wrote a counter balanced red-black tree in C++. The balanced trees have a counter in each node, which represent the number of nodes under it including itself. This counter permit to access to the nodes by their position in the tree. Due to this you can use a counter tree as a vector, access by position and insert and delete by position. Of course, the iterators of this trees have random access, an you can add or decrement the iterators any value . vector_tree<int>::iterator Alfa, Beta ; Alfa = Beta + 17 ; The algorithms are built from zero,without any book or article, because you need in each operation , not only modify the pointers, you must modify the counters too. The speed is good. In the worst case the delay respect to the equivalent STL functions is around 20%. I had checked in windows ( Visual Studio ) and Linux (GCC). My version have a 5 classes interface : vector_tree : This class is a counter balanced red-black tree and have the same interface than the STL class vector. The insertion , deletion and access to elements are log(N) operations. The other four classes are set , multiset , map and multimap. Internally they have a vector_tree. They have the same interface than the STL classes, plus the access by position and the random access iterators. My idea is to send you to examine , and if you think useful, make a new boost library. Today is finished to 95% . I hope have all finished by the first weeks of September. I am writing you because today, looking for other think I discovered a US patent “Positional access using a B-tree” ( US patent Number 7,120,637B2 Oct, 10, 2006), and I don't know if this patent prevent the publication of the code in your library, because you can consider the red-black trees an simplification of B-trees If prevent, and you don't have an idea about the utility of the code, I will stop the develop, and I will spend my time with new ideas The idea about the counter trees you can find in “The art of computer Programming “ Donald Knuth, and I have a previous version of this code wrote 10 years ago and presented in my exposition in the Oposiciones a Catedrático de Informática ( Madrid 2001) If you are interested in the code, mail me and I will send you. Francisco José Tapia E-Mail : fjtapia(a)gmail.com

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