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

adding elements to a std::container in a single expression
by Peter Foelsche 14 Aug '11

14 Aug '11

until now I've usually written my own template to do this: template<typename T> struct push_back_container:T { push_back_container &_push_back(const typename T::value_type &_r) { push_back(_r); return *this; } }; one can use this like this: push_back_container<std::vector<something> >()._push_back(something1)._push_back(_something2) Is there some more elegant way to do this? Peter

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[C++0x] ISO/IEC approves C++0x standard!
by Beman Dawes 13 Aug '11

13 Aug '11

The C++0x standard has been approved by ISO/IEC. The vote was unanimous; all 21 National Bodies voting were in favor. That means the dozen or so Boost libraries that were in TR1 are now part of the standard itself. Good work, Boosters! --Beman

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[serialization] unregistered class exception when using BOOST_CLASS_EXPORT_GUID
by Ron Hashimshony 13 Aug '11

13 Aug '11

Hi all boost users, We have been using boost.serialization for years. We want to move from 1.33 to 1.47 and encountered a problem. Many of our classes are abstract, and the derived are defined with BOOST_CLASS_EXPORT_GUID. At one point in time, a new class (B) was added that derives from a class that was defined with the BOOST_CLASS_EXPORT_GUID macro (A). It all worked well in 1.33. In 1.47, when we get to de-serialize class A, we get an exception of unregistered class. We traced it down, and found out that if we remove the derived class (B), it works fine, but this is not an option, and then the derived class (B) cannot be de-serialized from the file... If there any way to bypass this problem? was there a change made that broke this functionality? Many Thanks! Ron

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Re: [Boost-users] [!! SPAM] [Boost.Wave] util::file_position<> and asserted !is_escaped_lit(..) requirement
by Hartmut Kaiser 13 Aug '11

13 Aug '11

> (Using namespace boost::wave here on.) > > It seems that util::file_position<> has an assertion that checks if a > given filename contains any following sequences: <\\>, <\"> or <\?> (using > util::debug::is_escaped_lit). > > I wonder why file_position<> does need to check this and if it's so > crucial why it's done using a mere BOOST_ASSERT? > > Now, here's comes the reason why I'm asking this: At least with MSVC9's > remote debugger (or some other lowlevel component; not really the > interesting part > here) translates all network shares on a remote computer to UNC-paths. > This is correct behaviour and actually a very neat feature. However, as > you might be already aware at this point this leads to the actual problem: > Any UNC-path triggers (consider <\\foo\path\file>) the assertion and > things go boom. > > It is not possible to easily work around this by refactoring user code > and/or input values as provided filenames are completed internally using > util::complete_path (after which <file> becomes <\\foo\path\file> etc. in > this case). > > I tried to disable this assertion (actually, there's two; one in the > constructor and one in the set_file member function) and didn't see any > strange behaviour. E.g. std::ifstream handling with UNC-paths in > iteration_context_policies::load_file_to_string::inner<> worked just fine, > as expected from a native STL. > > Goes without saying that I'm using the latest Boost version (1.47.0). I > would be very pleased if anyone could shed some light on this matter or > better still > - fix it permanently. Right, that's apparently a leftover from old boost.filesystem times, when it did not support UNC paths. I'll remove the checks asap. Regards Hartmut --------------- http://boost-spirit.com

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[serialization] overloading load_construct_data: no accessible constructor at all
by Griffin Howlett 13 Aug '11

13 Aug '11

Hey, so I'm using the boost::serialization library, and I'm trying to override how a class is constructed, since it has no default constructor. This is demonstrated here<http://www.boost.org/doc/libs/1_47_0/libs/serialization/doc/serialization.h…>. To me it appears the function ONLY takes the `class* t` and then sets it to point to a newly constructed object. If I'm wrong, this is definitely the source of my error. However, the only way to construct my class is by using another classes `create()` function, meaning I need to stray from the code in the example (this is stated in the boost::serialization namespace): `::new(t)my_class(attribute);` I tried simply calling the create function and setting `t` equal to the returned pointer, but this doesn't seem to work because right after the `load_construct_data function`, and in the `serialization function`, the given `myClass&` is not the same as what I set 't' to. *How do I do whatever ::new(t) is doing so the object created using the create function follows through into the serialize/other functions?* [1]: http://www.boost.org/doc/libs/1_47_0/libs/serialization/doc/serialization.h…

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JSON Property file reader compile problem
by Scott Smith 13 Aug '11

13 Aug '11

I'm trying to use the boost property tree to read a json file. I'm using 1.46 on gcc 4.6 (Fedora 15). I'm also running on Eclipse (Indigo) which is relevant for something I mention below. Here's the issue . I have a JSON file which has an array of parameters which looks something like: { "config": { "modules": [ { "name": "somename0", "param1": "someparam", "param2":"someotherparm" }, { "name": "somename1", "param1": "someparam", "param2":"someotherparm" }, { "name": "somename2", "param1": "someparam", "param2":"someotherparm" } ] } } So, I wrote the following code (Note that I can't use boost:FOR_EACH because of some bug in eclipse (#332278) which causes an error-or so I believe): ptree v = pt.get<ptree>("config.modules"); for (ptree::iterator it = v.begin() ; it != v.end ; ++it) { ptree module = ???; } The first two lines seem to compile fine. I'm assuming that what I get from v is the "root" ptree (the parent) for the various "modules" objects and that the iterator will walk through them. However, I've tried all sorts of things trying to get at the module data (e.g., it->second, (*it)->second, ...) and clearly I don't know what it is I need to tell the compiler I want. All I get are compile errors. The compiler is giving me no hints as to what I need to tell it. Can someone tell me what I'm missing here? Thanks Scott

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(no subject)
by Hasanul Ferdaus 12 Aug '11

12 Aug '11

<p>living paycheck to paycheck wasnt working for me I told myself to stay positive without this id still be completely distraught!<br><a href="http://salanowyswiat.home.pl/PhilipBennett68.html">http://salanowyswiat.home.pl/PhilipBennett68.html</a> I waited so long for my time to shine<br></p>

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[ASIO] Send data on a socket
by Claude 12 Aug '11

12 Aug '11

I created a socket with BOOST asio and I use it in a server process that accepts connections from "remote" client. It is possible from the process that created the socket, send data to the same socket simulating the arrival of data from a client process? -- View this message in context: http://boost.2283326.n4.nabble.com/ASIO-Send-data-on-a-socket-tp3738099p373… Sent from the Boost - Users mailing list archive at Nabble.com.

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[Boost.Wave] util::file_position<> and asserted !is_escaped_lit(..) requirement
by Pekka Seppänen 12 Aug '11

12 Aug '11

Hello. (Using namespace boost::wave here on.) It seems that util::file_position<> has an assertion that checks if a given filename contains any following sequences: <\\>, <\"> or <\?> (using util::debug::is_escaped_lit). I wonder why file_position<> does need to check this and if it's so crucial why it's done using a mere BOOST_ASSERT? Now, here's comes the reason why I'm asking this: At least with MSVC9's remote debugger (or some other lowlevel component; not really the interesting part here) translates all network shares on a remote computer to UNC-paths. This is correct behaviour and actually a very neat feature. However, as you might be already aware at this point this leads to the actual problem: Any UNC-path triggers (consider <\\foo\path\file>) the assertion and things go boom. It is not possible to easily work around this by refactoring user code and/or input values as provided filenames are completed internally using util::complete_path (after which <file> becomes <\\foo\path\file> etc. in this case). I tried to disable this assertion (actually, there's two; one in the constructor and one in the set_file member function) and didn't see any strange behaviour. E.g. std::ifstream handling with UNC-paths in iteration_context_policies::load_file_to_string::inner<> worked just fine, as expected from a native STL. Goes without saying that I'm using the latest Boost version (1.47.0). I would be very pleased if anyone could shed some light on this matter or better still - fix it permanently. Br, Pekka

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async_read_some() not found??
by Claude 12 Aug '11

12 Aug '11

I have this code (from async_read_until boost documentation): boost::asio::streambuf b; void handler(const boost::system::error_code& e, std::size_t size) { if (!e) { std::istream is(&b); std::string line; std::getline(is, line); // ... } } boost::asio::async_read_until(s, b, "\r\n", handler); But I obtain this error on Ubuntu 11.04 (boost 1.45.0): boost/asio/impl/read_until.hpp|388|*error: request for member ‘async_read_some’* in ‘((boost::asio::detail::read_until_delim_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp>*, std::allocator<char>, void (*)(const boost::system::error_code&, unsigned int)>*)this)->boost::asio::detail::read_until_delim_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp>*, std::allocator<char>, void (*)(const boost::system::error_code&, unsigned int)>::stream_’, which is of non-class type ‘boost::asio::basic_stream_socket<boost::asio::ip::tcp>*’ I Included in my project: libpthread libboost_system -- View this message in context: http://boost.2283326.n4.nabble.com/async-read-some-not-found-tp3732368p3732… Sent from the Boost - Users mailing list archive at Nabble.com.

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