March 2011 - Boost-users - lists.preview.boost.org

How to skip a sub-directory with filesystem3::recursive_directory_iterator in case of exception?
by Tan, Tom (Shanghai) 30 Mar '11

30 Mar '11

I am iterating a mapped network drive under windows, K:\, under which are 3 sub directories A, B, C, where K:\B is only visible itself but cannot be iterated into due to group policy. With code below: boost::system::error_code ec; for (recursive_directory_iterator itr(root, ec), itr_end; itr!=itr_end; itr++) { ... } It throws in itr++ when itr->path() == "K:\B". I would like to skip going into k:\B and go on with K:\C, so I code like this: for (recursive_directory_iterator itr(root, ec), itr_end; itr!=itr_end; ) { ... ; itr.increment(ec); } It does not solve my problem, but introduces one more: itr will never equal to itr_end even though all item are iterated over, and this happens for any normal folder such as K:\A. thus never get's out of for loop until the internal vetor<directory_iterator>::operator+=() asserts. Again, I tried something like below. for (recursive_directory_iterator itr(root, ec), itr_end; itr!=itr_end; ) { ... ; itr.increment(ec); if(ec) itr.pop(); } This time itr.pop() assertion fails because "pop() on recursive_directory_iterator with level < 1" Anybody got some advice? Thanks.

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GSOC 2011
by Rafael González 30 Mar '11

30 Mar '11

Hello I would like to participate with Boost in GSOC 11. I have some ideas about arbitrary precision and a Monte Carlo simulation framework. I've already seen the time line and I know that applications begin today, so, should I prepare it right now or I we have time to discuss it with someone. Thanks

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Matrix initialization in uBLAS
by Oscar Vargas 30 Mar '11

30 Mar '11

It's the first time I use uBLAS, and I want to know the right way to initialize a matrix. Example: | 3 2| M = | 1 5| | 3 4| How can I create such a matrix? For example, in Matlab, you can type: >> M = [3, 2; 1, 5; 3, 4] I haven't found documentation for something as simple as that!!! I need help!

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Re: [Boost-users] [context review] Review starts today, Mars 21st 2011
by Vicente BOTET 29 Mar '11

29 Mar '11

> Message du 21/03/11 02:21 > De : "Nat Linden" > A : boost-users(a)lists.boost.org > Copie à : > Objet : Re: [Boost-users] [context review] Review starts today, Mars 21st 2011 > > On Sun, Mar 20, 2011 at 8:18 PM, Vicente BOTET wrote: > > > The review of Oliver Kowalke Context library starts today Mars 21st 2011, and will end on Mars 30th. > > > > I really hope to see your vote and your participation in the discussions on the Boost DEVELOPMENT mailing lists! > > WARNING !!!!!!!!!!!!! Only on the Boost DEVELOPMENT mailing lists > > :-( > > I am not presently on the development mailing list; I am reluctant to > register because keeping up with the boost-users list already takes a > surprising amount of my time. > > I have opinions and a bit of experience with the topic area of this > library, and I was planning to submit a review. But I feel rebuffed. > > Perhaps I could submit a review on this list and have you, the review > manager, helpfully forward it to the development list? Hi Nat, I'm really sorry to miss your post. I should read the Users ML before , but as you can see I'm used to read only the dev ML as you are used to read only the user ML. I think that I should change my habits as Boost.Chrono and Boost.Ratio should be released in the next release :) As Michael has explained it is difficult for the review manager, the author and the other reviewers to follow the review in two ML. I hope you can understand that. As Vladimir said you can post the review to the dev ML and follow up the review using some archives as nabble boost dev for example. If you are yet interested in making a review I will accept it on this ML exceptionally as the review is almost finished. I will forward to the dev ML. Waiting for your review, Vicente

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Re: [Boost-users] [all libs] compatibility
by Pace, Antony [Harman Pro Group UK] 29 Mar '11

29 Mar '11

I am using boost::asio on a small FPGA core running NIOS and uCos and having problems. After reading documentation I now understand that asio is only implemented for a number of platforms; albeit the bigger platforms. I see other messages on this forum about platform compatibility and am getting more and more disillusioned with Boost. I thought the whole point was that boost libraries only needed a compliant compiler. I understand that for TCP/IP and timers there needs to be some interoperability with the underlying operating system. I understand for example that timers can plug into posix or Windows timers but I can't understand why the boost libraries themselves have #ifdef WINVER statements in them. I could understand that to run libraries such as asio on my OS I need to implement a set of functionality and can imagine those being available for popular OSes such as Windows and Linux separately, ie outside the scope of Boost. Would it not be possible to have well defined OS interfaces for all libraries that are OS dependent and would that not be more in the spirit of Boost and ultimately C++ and STL? Many thanks for your thoughts. Ant [cid:image001.png@01CBEE31.17904490] Cranborne House, Cranborne Road, Potters Bar, Herts, EN6 3JN Phone: +44 1707 668025 Email: antony.pace(a)harman.com Skype: antony.pace.harman Web: www.harman.com ANTONY PACE Senior Software Engineer Soundcraft Studer R&D Confidentiality Notice: This e-mail message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorised review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by return e-mail and destroy all copies of the original message.

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[context review] Review ends tomorrow Mars 30st 2011
by Vicente BOTET 29 Mar '11

29 Mar '11

Hi all, The review of Oliver Kowalke Context library ends tomorrow Mars 30th. If you have taken already a look at the library, please make a review even if you can do only a short one. Let me know if you think you need more time to do a deeper review, so I can see with Oliver and the review wizards if we can extend the library. Best regards, Vicente Review Manager Boost.Context is a basic building block library that is used for more higher abstractions. It is used by Boost.Fiber, Boost.Tasklet and Boost.Task from the same author. I really hope to see your vote and your participation in the discussions on the Boost DEVELOPMENT mailing lists! WARNING !!!!!!!!!!!!! Only on the Boost DEVELOPMENT mailing lists Please use [context review] as prefix of your post to make easier the review follow up. You can download a frozen version for the review from the Vault, TinyURL: http://tinyurl.com/5r77rel or The documentation is available directly here: http://ok73.ok.funpic.de/boost/libs/context/doc/html/ --------------------------------------------------- About the library: Boost.Context provides a possibility to switch between different user-level context and is intended to be the basis for a higher abstraction like coroutine and fiber. A user-level context represents the current execution state, including all registers and CPU flags, the instruction pointer, the stack pointer. boost::context encapsulates such a user-level context and is able to store/restore its associated user-level context. This allows multiple execution paths running on a single thread using a sort of cooperative scheduling (in contrast a thread is preemptively scheduled) - the running boost::context decides explicitly when its yields to allow another boost::context to run (user-level context switching). A context can only run on a single thread at any point in time but may be migrated between thread. A context switch between threads costs usually thousands of CPU cycles on x86 compared to a user-level context switch with few hundreds of cycles. Boost.Context differes to setjmp()/longjmp() in the fact that the C99 standard does not require that longjmp() preserves the current stack frame, e. g. jumping into a function which was exited via a call to longjmp() is undefined. Boost.Context allows to select the mechanism provided by the operating system (ucontext on UNIX, Windows Fibers on Windows) or a faster implementation provided by this library (fcontext using assembler). --------------------------------------------------- Please always state in your review, whether you think the library should be accepted as a Boost library! Additionally please consider giving feedback on the following general topics: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With what compiler? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain?

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[enable_if] How to enable a constructor
by Michael Kaes 29 Mar '11

29 Mar '11

Hi all, I am playing around with enable_if and I want to create a constructor switch. The code is the following: ------------------------------------------------ struct NullType{}; struct TestType{}; struct NonNull{}; template<typename T, typename U = NullType> struct TemplateStruct { TemplateStruct(int i, typename boost::enable_if<boost::is_same<U, NullType>, void* >::type dummy = 0) { std::cout << "One Param == " <, void* >::type dummy = 0) { std::cout << "Two Param == " <(1); TemplateStruct<TestType,NonNull>(1,2); return 0; } ------------------------------------- I want that the first Ctor is only available when a NullType is passed in and if not that the second one is available but not the first. I don't want to do a class specialization because the class is rather big and extracting all the methods to a common class would be difficult. So how can I reuse the template parameter U for the Ctors enable_if? Or is this simply not possible? Regards, Michael

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Ref: FW: Platform Compatibility (Shahriar, Khandaker (CONT))
by Avi Bahra 29 Mar '11

29 Mar '11

>Good Afternoon, >Please verify if Boost Library is compatible with HPUX 11.x or AIX? Please note there is not a single boost library. HPUX --------- Boost does not officially support HPUX. However I have managed to build boost successfully with version 1.45 using HPUX compiler vapp, with the following compiled libraries: boost_serialization boost_system boost_thread boost_test boost_test_monitor boost_program_options boost_filesystem boost_datetime boost_python and use the following header only libs: smart pointer, bind, ASIO, lexical_cast, utility, lambda spirit classic Note ASIO < 1.45 was broken, than has now been fixed in 1.45 Occasionally I have had to hack boost to get it to compile. Up to boost 1.38 I used gcc on HPUX. AIX ----- All of the libraries mentioned above should work fine on v11.1 c++ compiler However please note: the boost serialisation is broken in release mode, and has been for quite a while. Also there are problems with spirit.qi You need to look at each library individually to see if it works for you. Best regards, Ta, Avi

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[Fusion] Assignement from adapted struct to tuple
by Samuel Debionne 29 Mar '11

29 Mar '11

Hello all, While I managed to assign an adapted structure to a fusion vector, I fail to assign the same structure to a legacy tuple. The doc doesn't mention the assignement operator between two sequences, but I though it would work. Am I missing something ? #include <boost/fusion/include/vector.hpp> #include <boost/fusion/include/adapt_struct.hpp> #include <boost/fusion/include/boost_tuple.hpp> struct my_struct { double a; int b; char c; }; BOOST_FUSION_ADAPT_STRUCT( my_struct, (double, a) (int, b) (char, c)); my_struct src; boost::fusion::vector<double, int, char> dest1 = src; //OK boost::tuple<double, int, char> dest2 = src; //Fails Samuel

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FW: Platform Compatibility
by Shahriar, Khandaker (CONT) 29 Mar '11

29 Mar '11

Good Afternoon, Please verify if Boost Library is compatible with HPUX 11.x or AIX? Thx! Khan 804-284-7201 </pre> The information contained in this e-mail is confidential and/or proprietary to Capital One and/or its affiliates. The information transmitted herewith is intended only for use by the individual or entity to which it is addressed. If the reader of this message is not the intended recipient, you are hereby notified that any review, retransmission, dissemination, distribution, copying or other use of, or taking of any action in reliance upon this information is strictly prohibited. If you have received this communication in error, please contact the sender and delete the material from your computer. </pre>

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[boost::condition_variable_any] Telling cond to unlock_share()
by Panagiotis Foteinos 28 Mar '11

28 Mar '11

Hello users. Documentation says that cond.wait(mtx) blocks the current thread and invokes mtx.unlock(). What if I want cond.wait(mtx) to call mtx.unlock_shared() instead? Is there any way to do so? Regards, Panagiotis Foteinos

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OT: Why can't I insert a vector of int
by Patrick Horgan 28 Mar '11

28 Mar '11

I simplified this as much as possible and it turned into a template question, and not a boost question, but I hope that someone here will take a second and answer it anyway. I don't know of another mailing list with the expertise of this one in templates. In the below, the inserter for vector<int> is never used, instead, since the vector<int> is a type, it matches the simpler inserter for T. How can I make it work the way I want it to? #include <iostream> #include <vector> struct theclass { template<typename T> void operator<<(const T& t){ std::cout << "Got a T\n"; } template<typename T> void operator<<(std::vector<const T> t){ std::cout << "Got a vector of T\n"; } }; int main() { std::vector<int> vi; int i; theclass f; f << i; f << vi; }

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Re: [Boost-users] Regex question: is this a bug or a feature?
by Jerry 28 Mar '11

28 Mar '11

Kulti <kultihell <at> gmail.com> writes: > Ramon F Herrera <ramon <at> patriot.net> wrote: > > My pattern matching was failing when I had these definitions, > > which I happen to prefer: > > > > const string number = "[0-9]+"; > > const string name = "[A-z][A-z0-9]*"; > > > > The program is working fine now, after I am using these ones: > > > > const string number = "\\d+"; > > const string name = "[A-z]\\w*"; > > > > Could you please read documentation before posting question? > http://www.boost.org/doc/libs/1_45_0/libs/regex/doc/html/boost_regex/syntax… racter_classes/std_char_clases.html > "w - Any word character (alphanumeric characters plus the underscore)" > Actually I don't think he was asking why w included underscores - I think he was asking why that worked and his original character class based regex didn't. Jerry

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Boost::Polygon issue with including in project
by Chris Stylianou 28 Mar '11

28 Mar '11

I'm having an issue trying to use Boost::Polygon, I've added boost/polygon/polygon.hpp but when I try to compile I get: boost/polygon/transform.hpp:147: error: expected identifier before numeric constant boost/polygon/transform.hpp:147: error: expected `}' before numeric constant boost/polygon/transform.hpp:147: error: expected unqualified-id before numeric constant boost/polygon/transform.hpp:219: error: expected unqualified-id before ')' token boost/polygon/transform.hpp:220: error: expected `)' before 'atr' boost/polygon/transform.hpp:221: error: expected unqualified-id before 'const' boost/polygon/transform.hpp:221: error: expected `)' before 'const' boost/polygon/transform.hpp:222: error: expected unqualified-id before 'const' boost/polygon/transform.hpp:222: error: expected `)' before 'const' boost/polygon/transform.hpp:223: error: expected unqualified-id before 'const' boost/polygon/transform.hpp:223: error: expected `)' before 'const' boost/polygon/transform.hpp:224: error: expected unqualified-id before 'const' boost/polygon/transform.hpp:224: error: expected `)' before 'const' boost/polygon/transform.hpp:225: error: expected unqualified-id before 'const' boost/polygon/transform.hpp:225: error: expected `)' before 'const' boost/polygon/transform.hpp:228: error: 'boost::polygon::axis_transformation& boost::polygon::operator=(const boost::polygon::axis_transformation&)' must be a nonstatic member function boost/polygon/transform.hpp:231: error: expected ',' or '...' before '&' token boost/polygon/transform.hpp:231: error: 'boost::polygon::axis_transformation& boost::polygon::operator=(int)' must be a nonstatic member function boost/polygon/transform.hpp:234: error: non-member function 'bool boost::polygon::operator==(const boost::polygon::axis_transformation&)' cannot have cv-qualifier boost/polygon/transform.hpp:234: error: 'bool boost::polygon::operator==(const boost::polygon::axis_transformation&)' must take exactly two arguments boost/polygon/transform.hpp:237: error: non-member function 'bool boost::polygon::operator!=(const boost::polygon::axis_transformation&)' cannot have cv-qualifier boost/polygon/transform.hpp:237: error: 'bool boost::polygon::operator!=(const boost::polygon::axis_transformation&)' must take exactly two arguments boost/polygon/transform.hpp:240: error: non-member function 'bool boost::polygon::operator<(const boost::polygon::axis_transformation&)' cannot have cv-qualifier boost/polygon/transform.hpp:240: error: 'bool boost::polygon::operator<(const boost::polygon::axis_transformation&)' must take exactly two arguments boost/polygon/transform.hpp:243: error: non-member function 'boost::polygon::axis_transformation boost::polygon::operator+(const boost::polygon::axis_transformation&)' cannot have cv-qualifier boost/polygon/transform.hpp:246: error: 'boost::polygon::axis_transformation& boost::polygon::operator+=(const boost::polygon::axis_transformation&)' must take exactly two arguments boost/polygon/transform.hpp:250: error: non-member function 'void boost::polygon::populate_axis_array(boost::polygon::INDIVIDUAL_AXIS*)' cannot have cv-qualifier boost/polygon/transform.hpp:255: error: non-member function 'void boost::polygon::get_directions(boost::polygon::direction_2d&, boost::polygon::direction_2d&)' cannot have cv-qualifier boost/polygon/transform.hpp: In function 'void boost::polygon::get_directions(boost::polygon::direction_2d&, boost::polygon::direction_2d&)': ........etc ....... Thanks Chris

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Re: [Boost-users] lambda - if_then_else - Compiler can not deduce my Arguments
by Simon Adler 28 Mar '11

28 Mar '11

Hey Thomas > On Mon, Mar 28, 2011 at 11:16 AM, Thomas Heller < > thom.heller(a)googlemail.com> wrote: > >> On Monday, March 28, 2011 11:34:45 AM Simon Adler wrote: >> >> > class XML_Element >> > { >> > public: >> > const std::string & getName(void); >> > }; >> > >> > class HandleStuff >> > { >> > void handleTransformations( XML_Element * node ); >> > void handleLinks( XML_Element * node ); >> > >> > >> > void handle ( std::list<XML_Element *> * nodes ) >> > { >> > // what i want to do via boost and which will do the job >> > for (std::list< XML_Element *>::iterator it = nodes->begin(); it != >> > nodes->end(); it++) >> > { >> > if ( (*it)->getName() == "Transform" ) handleTransformations(*it); >> > else handleLinks(*it); >> > } >> > >> > // what i tried >> > std::for_each( nodes->begin(); nodes->end(), >> > boost::lambda::if_then_else( boost::bind(&XML_Element::getName, _1) >> == >> > std::string("Transform"), >> > >> > boost::bind<void>(&HandleStuff::loadTransformations, this, _1), >> > >> > boost::bind<void>(&HandleStuff::loadLinks, this, _1) ) >> > } >> > >> > } >> >> The error you made is that you mixed boost bind with lambda, which is not >> compatible. >> >> A solution with Phoenix looks like this: >> >> using boost::phoenix::arg_names::_1; >> using boost::phoenix::bind; >> using boost::phoenix::if_; >> >> std::for_each( nodes->begin(), nodes->end(), >> if_(bind(&XML_Element::getName, _1) == "Transform") >> [ >> bind(&HandleStuff::handleTransformations, this, _1) >> ] >> .else_ >> [ >> bind(&HandleStuff::handleLinks, this, _1) >> ] >> ); >> > Yes, it worked. I did not know Phoenix and included now boost/spirit/include/phoenix.hpp - quite big during compilation. It solved my Problem, but if this is a type missmatch - how can i solve this without Phoenix. I have to understand what is going on. I tried to solve this with explicit namespace declarations and replaced _1 via boost::lambda::_1 I also tried to replace all with ::_1 which should explicitly take the declarations from bind/placeholders.hpp thouse are in an unnamed namespace. Please - how can I solve this without using Phoenix? - Not that i don't like your solution but i will understand. Simon

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lambda - if_then_else - Compiler can not deduce my Arguments
by Simon Adler 28 Mar '11

28 Mar '11

Hello, i need a hint about boost::bind and lambda. Following (reduced) case: class XML_Element { public: const std::string & getName(void); }; class HandleStuff { void handleTransformations( XML_Element * node ); void handleLinks( XML_Element * node ); void handle ( std::list<XML_Element *> * nodes ) { // what i want to do via boost and which will do the job for (std::list< XML_Element *>::iterator it = nodes->begin(); it != nodes->end(); it++) { if ( (*it)->getName() == "Transform" ) handleTransformations(*it); else handleLinks(*it); } // what i tried std::for_each( nodes->begin(); nodes->end(), boost::lambda::if_then_else( boost::bind(&XML_Element::getName, _1) == std::string("Transform"), boost::bind<void>(&HandleStuff::loadTransformations, this, _1), boost::bind<void>(&HandleStuff::loadLinks, this, _1) ) } } got an error, that the compiler can not deduce a template Argument, but i do not understand what the compiler tries to say. I am new to bind and lambda and i like it a lot, but in some cases the Error-Messages are hard to understand. Thank you for any advice. Please understand, that this example is a reduced Version what is realy going on, so i only give the Functions Interfaces. Simon

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Regex question: is this a bug or a feature?
by Ramon F Herrera 28 Mar '11

28 Mar '11

My pattern matching was failing when I had these definitions, which I happen to prefer: const string number = "[0-9]+"; const string name = "[A-z][A-z0-9]*"; ("name" is supposed to match a typical variable name) The program is working fine now, after I am using these ones: const string number = "\\d+"; const string name = "[A-z]\\w*"; The only difference that I aware of, is that the second form accepts underscores as part of variable names. TIA, -RFH

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[test]
by Stirling Westrup 28 Mar '11

28 Mar '11

I have been using Boost.test to run some simple unit tests as I build my code. I've come across a case where I need to test if my code runs within an acceptable time limit. I know that the execution monitor has a timeout system for testing that sort of thing, but I can't figure out how it is supposed to be integrated into the unit test framework. Ideally, I'd love to just have a BOOST_CHECK_TIMED( f(), timeout) that I could invoke to ensure that the code returns true, and returns within the specified timeout interval. -- Stirling Westrup Programmer, Entrepreneur. https://www.linkedin.com/e/fpf/77228 http://www.linkedin.com/in/swestrup http://technaut.livejournal.com http://sourceforge.net/users/stirlingwestrup

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[boost::shared_ptr] Memory is not freed
by Panagiotis Foteinos 28 Mar '11

28 Mar '11

Hello users. In the past, I wrote a program using the C++ built-in pointers. I made sure that there was not any memory leak: indeed, valgrind reported no memory leaks. I decided to switch to boost::shared_ptr, and replaced all the C++ built-in pointers with boost:shared_ptr ones. Interestingly, valgrind now reports a huge memory leak. I thought that by just replacing the built-in pointers with the boost::shared_ptr pointers (forgetting about explicit deletes of memory) would be enough. Note that I use boost::make_shared<> for memory allocations. I wish I could include the code in this email, but it is very long and complicated. Therefore, I am kindly asking you to guess what might have been wrong with the boost:shared_ptr. Could you think of any scenarios that would cause the observed bahavior? Any ideas would be welcome. OS: Ubuntu 64 Compiler: gcc version 4.4.3 Best Regards, Panagiotis Foteinos

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[serialization] empty xml output
by Olivier Tournaire 27 Mar '11

27 Mar '11

Hi all, I am trying to introduce XML serialization in my project, but even with the simplest test, I cannot get something to work. Here is what I did: #define PARAMETERS_HPP #include <boost/archive/xml_iarchive.hpp> #include <boost/archive/xml_oarchive.hpp> #include <iostream> class rss_feeds_to_parse { public: bool all; template<class Archive> void serialize(Archive & ar, const unsigned int file_version) { ar & BOOST_SERIALIZATION_NVP(all); } }; class parameters { public: rss_feeds_to_parse feeds; template<class Archive> void serialize(Archive & ar, const unsigned int file_version) { ar & BOOST_SERIALIZATION_NVP(feeds); } }; #endif // PARAMETERS_HPP Later, in my main, I have: parameters p; p.feeds.all = true; std::ofstream ofs("test_parameters.xml"); assert(ofs.good()); boost::archive::xml_oarchive oa(ofs); oa << BOOST_SERIALIZATION_NVP(p); It compiles, links and executes well, the file test_parameters.xml is created ... but empty ! What am I doing wrong? Hope you could help. Best regards, Olivier

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Re: [Boost-users] Boost-users Digest, Vol 2674, Issue 3
by Jim Hodapp 27 Mar '11

27 Mar '11

Ian, That's excellent, thanks! Is g++ the compiler with the most of the c++0x specification implemented and the best to experiment with the new features? Thanks, Jim On Mar 27, 2011, at 12:00 PM, boost-users-request(a)lists.boost.org wrote: > > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Boost-users digest..." > Today's Topics: > > 1. C++0x resources (Jim Hodapp) > 2. Re: C++0x resources (Ian Bruntlett) > > From: Jim Hodapp <james.hodapp(a)gmail.com> > Date: March 27, 2011 10:53:09 AM EDT > To: boost-users(a)lists.boost.org > Subject: [Boost-users] C++0x resources > Reply-To: boost-users(a)lists.boost.org > > > Hi all, > > I just saw in another post that C++0x FDIS has been voted complete and ready to ship. Is there a good website (or book) that I can start reading to get familiar with the new features? I've seen a few resources here and there on one or two topics, such as "auto", but no good place to read and see example for every new feature. Is the GNU g++ compiler the best implementation to experiment with these new language features? > > -Jim > > > > > > > From: Ian Bruntlett <ian.bruntlett(a)gmail.com> > Date: March 27, 2011 11:27:42 AM EDT > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] C++0x resources > Reply-To: boost-users(a)lists.boost.org > > > Hi Jim, > > On 27 March 2011 15:53, Jim Hodapp <james.hodapp(a)gmail.com> wrote: > I just saw in another post that C++0x FDIS has been voted complete and ready to ship. Is there a good website (or book) that I can start reading to get familiar with the new features? I've seen a few resources here and there on one or two topics, such as "auto", but no good place to read and see example for every new feature. Is the GNU g++ compiler the best implementation to experiment with these new language features? > > Take a look at Bjarne Stroustrup's C++ 0x FAQ:- > http://www2.research.att.com/~bs/C++0xFAQ.html > > HTH, > > > Ian > > -- > -- ACCU - Professionalism in programming - http://www.accu.org/ > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users

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C++0x resources
by Jim Hodapp 27 Mar '11

27 Mar '11

Hi all, I just saw in another post that C++0x FDIS has been voted complete and ready to ship. Is there a good website (or book) that I can start reading to get familiar with the new features? I've seen a few resources here and there on one or two topics, such as "auto", but no good place to read and see example for every new feature. Is the GNU g++ compiler the best implementation to experiment with these new language features? -Jim

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[C++0x] C++0x FDIS ships!
by Beman Dawes 27 Mar '11

27 Mar '11

On Friday In Madrid, Spain, the ISO C++ committee approved the Final Draft International Standard (FDIS) for C++0x. So C++0x is now complete in a technical sense. There is no possibility for further technical change. It will be a few weeks before the actual FDIS document is available. The ISO formal voting process will take until August or later. It's an up or down, yes or no, vote. All the countries actively participating voted yes for shipping the FDIS, so this ISO vote is mostly a formality. Most of the changes approved in Madrid were minor wording changes fixing mistakes in specification. Proposals to remove several features on the grounds they haven't been implemented or tested were rejected, usually by overwhelming vote margins. For example, the range-based-for-loop problem that surfaced on the Boost list caused a tweak in name lookup wording. On the library side, a lot of effort was devoted to "noexcept". A much more coherent set of usage guidelines was agreed on, and that meant going through the standard library and removing a lot of uses of "noexcept" that were over aggressive. More on that later, since Boost will probably want to use a similar set of guidelines. A straw poll for restarting work on Library Technical Report 2 passed without opposition. There was a lot of private discussion as to which Boost libraries committee members wanted to see go into TR2. --Beman

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[context review] Review will end Mars 30st 2011
by Vicente BOTET 27 Mar '11

27 Mar '11

Hi all, The review of Oliver Kowalke Context library will end on Mars 30th. There were a few interesting reviews with quite constructive comments. I encourage you to make a review so you can help improving the library and also help me to take the right decision ;-) Please let me know if you needs more time so I can see if the review could be extended. Vicente Review Manager Boost.Context is a basic building block library that is used for more higher abstractions. It is used by Boost.Fiber, Boost.Tasklet and Boost.Task from the same author. I really hope to see your vote and your participation in the discussions on the Boost DEVELOPMENT mailing lists! WARNING !!!!!!!!!!!!! Only on the Boost DEVELOPMENT mailing lists Please use [context review] as prefix of your post to make easier the review follow up. You can download a frozen version for the review from the Vault, TinyURL: http://tinyurl.com/5r77rel or The documentation is available directly here: http://ok73.ok.funpic.de/boost/libs/context/doc/html/ --------------------------------------------------- About the library: Boost.Context provides a possibility to switch between different user-level context and is intended to be the basis for a higher abstraction like coroutine and fiber. A user-level context represents the current execution state, including all registers and CPU flags, the instruction pointer, the stack pointer. boost::context encapsulates such a user-level context and is able to store/restore its associated user-level context. This allows multiple execution paths running on a single thread using a sort of cooperative scheduling (in contrast a thread is preemptively scheduled) - the running boost::context decides explicitly when its yields to allow another boost::context to run (user-level context switching). A context can only run on a single thread at any point in time but may be migrated between thread. A context switch between threads costs usually thousands of CPU cycles on x86 compared to a user-level context switch with few hundreds of cycles. Boost.Context differes to setjmp()/longjmp() in the fact that the C99 standard does not require that longjmp() preserves the current stack frame, e. g. jumping into a function which was exited via a call to longjmp() is undefined. Boost.Context allows to select the mechanism provided by the operating system (ucontext on UNIX, Windows Fibers on Windows) or a faster implementation provided by this library (fcontext using assembler). --------------------------------------------------- Please always state in your review, whether you think the library should be accepted as a Boost library! Additionally please consider giving feedback on the following general topics: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With what compiler? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? Have a good review, Vicente Review Manager

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filesystem::copy_directory for filesystem3 in 1.46.1 missing?
by Ákos Maróy 27 Mar '11

27 Mar '11

Hi, I'm trying to use the fileystem::copy_directory() function, in boost 1.46.1, using v3 of the filesystem library. I see that I have to reference this function by specifying the namespace boost::filesystem3 explicitly, instead of just boost::filesystem: #include <boost/filsystem.hpp> boost::filesystem::copy_directory(..) // does not compile boost::filesystem3::copy_directory(..) // compiles fine looking at boost/filystem/v3/operations.hpp, it seems that the copy_directory and the copy function is not 'exported' into the boost:filesystem namespace for some reason: namespace boost { namespace filesystem { using filesystem3::absolute; using filesystem3::block_file; using filesystem3::character_file; // using filesystem3::copy; using filesystem3::copy_file; using filesystem3::copy_option; using filesystem3::copy_symlink; ... I wonder if this is on purpose, or if this is some sort of omission... Akos

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