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[Range] Predicate type checking.
by Robert Jones 02 May '12

02 May '12

I'm pretty sure I'm have a 'Doh!' moment here, but why does this compile? Surely the last line of main is gibberish; the value type of m is pair, not S, so int_from_S is not a valid function? #include <boost/range.hpp> #include <boost/range/adaptor/transformed.hpp> #include <map> struct S { S( ) { } int i; }; int int_from_S( S s ) { return s.i; } int main( ) { std::map<unsigned, S> m; m[0]=S(); m | boost::adaptors::transformed(int_from_S); } Thx, - Rob.

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config. how to check if std::shared_ptr & std::scoped_ptr availability?
by niXman 02 May '12

02 May '12

Hello! I need to check if std::shred_ptr & std::scoped_ptr availability. I read boost.config and found: http://www.boost.org/doc/libs/1_49_0/libs/config/doc/html/boost_config/boos… But in this list don't exist macro that I need. Ideas? Thanks. -- Regards, niXman

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multiarray sub_array
by Petros 01 May '12

01 May '12

Hi, I want to be able to create an array view on a subset of a multi_array(MA)’s dimensions. So, say I have a MA of dimension M and I want to choose N (N <M) dimensions of it which I put on a boost::array. Say, I want to keep the entire range for each dimension. Is there a way to do this in a general fashion, i.e. w/out the use of the subscript operator on the indices object ? The documentation mentions something like : typedef boost::multi_array< double, 3 > Grid3D; typedef Grid3D::size_type size_type; typedef Grid3D::index index; typedef Grid3D::index_range index_range; typedef Grid3D::array_view<2>::type Slice2D; index_range r1; //( 0, iMax); index_range r3; //( 0, kMax); Grid3D::index_gen indices; Slice2D sliceJ2 = grid[indices [r1] [2] [r3] ]; but this is not sufficient for a generic construction. And also, what is the difference between array_view and subarray ? Thank you very much in advance, Petros

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fatal error C1001 with VS2010, boost 1.49, and shared_ptr.hpp
by Phillip Hellewell 01 May '12

01 May '12

I'm upgrading to boost 1.49 and getting this fatal error while compiling a source file that uses shared_ptr: 1>C:\mycomps\base\target\dependency\include\boost/smart_ptr/shared_ptr.hpp(362): fatal error C1001: An internal error has occurred in the compiler. 1> (compiler file 'msc1.cpp', line 1420) 1> To work around this problem, try simplifying or changing the program near the locations listed above. 1> Please choose the Technical Support command on the Visual C++ 1> Help menu, or open the Technical Support help file for more information Line 362 of shared_ptr.hpp is: shared_ptr( shared_ptr<Y> && r, typename boost::detail::sp_enable_if_convertible<Y,T>::type = boost::detail::sp_empty() ) Looks like the compiler is crashing with an access violation; any suggestions other than wait for a patch from Microsoft? I don't want to have to disable features like BOOST_HAS_RVALUE_REFS or BOOST_SP_NO_SP_CONVERTIBLE, but that may be my only choice :( Thanks, Phillip

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async_read_some
by Christer Borgqvist 01 May '12

01 May '12

Hi, Im playing around with the /boost_asio/example/http/server3 and using POST method. The bytes_transferred is 231, but thats only the header and ends with \r\n\r\n, need to read the rest. Sometimes i get bytes_transferred to 1032, the right amount of data, sometimes i get bytes_transferred = 231, but if i print the buffer_ i have all the 1032 bytes. Is it right that the bytes in the buffer_ and the bytes_transferred is not the same? appreciate any help. /christer void connection::handle_read(const boost::system::error_code& e, std::size_t bytes_transferred) { if (!e) { boost::tribool result; boost::tie(result, boost::tuples::ignore) = request_parser_.parse( request_, buffer_.data(), buffer_.data() + bytes_transferred); if (result) { request_handler_.handle_request(request_, reply_); boost::asio::async_write(socket_, reply_.to_buffers(), strand_.wrap( boost::bind(&connection::handle_write, shared_from_this(), boost::asio::placeholders::error))); } else if (!result) { reply_ = reply::stock_reply(reply::bad_request); boost::asio::async_write(socket_, reply_.to_buffers(), strand_.wrap( boost::bind(&connection::handle_write, shared_from_this(), boost::asio::placeholders::error))); } else { socket_.async_read_some(boost::asio::buffer(buffer_), strand_.wrap( boost::bind(&connection::handle_read, shared_from_this(), boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred))); } }

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Use boost::shared_ptr with boost::adaptors
by tolik levchik 01 May '12

01 May '12

The following code gives me segfault. But if `foo_ptr` is `foo*` it works fine. #include <vector> #include <boost/range/adaptor/indirected.hpp> #include <boost/range/adaptor/transformed.hpp> #include <boost/range/algorithm/for_each.hpp> #include <boost/bind.hpp> #include <boost/shared_ptr.hpp> struct foo{ foo(int _i): i(_i){} virtual void bar() const{ std::cout << "foo::bar::i " << i << std::endl; } int i; }; typedef boost::shared_ptr<foo> foo_ptr; //typedef foo* foo_ptr; foo_ptr trasform(int i){ return foo_ptr(new foo(i)); } int main(){ std::vector<int> vec; vec.push_back(1); using namespace boost::adaptors; using boost::bind; boost::for_each(vec | transformed(bind(&trasform, _1)) | indirected, bind(&foo::bar, _1)); } Is it expected behavior of adaptors ?

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Making my UdpConnection class thread safe
by Chris Dunphy 30 Apr '12

30 Apr '12

I have implemented some connection classes, using Boost ASIO, to replace some low level C code in an application, and everything is working great, except for one problem. Basically, I have a UdpConnection class that does synchronous read and write, but it uses async methods to handle time-outs as per the boost examples. The problem is I can't figure out how to make it threadsafe. I have tried adding strands to the event handlers to make this class threadsafe (code below), but that isn't working. I suspect it is because of the way timeout is implemented. I have included my code in 4 classes in pastebin. Single threaded is working fine. I also have TcpConnection and UnixSocketConnection classes that don't need to be shared amongst multiple threads and they work fine. However, I can't get multi-threaded UDP code to work. Am I missing something? Sources below: * Connection.h && AsioConnection.h http://pastebin.com/Cbbw37gL * UdpConnection.h && UdpConnection.cpp http://pastebin.com/VLnHBnPs

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[Boost.Optional] Compilation error with boost::optional in Boost 1.49 and GCC 4.4.6
by Jonathan Jones 30 Apr '12

30 Apr '12

Hello, The following code fails to compile when using GCC 4.4.6 and boost::optional from Boost 1.49: #include <boost/optional/optional.hpp> #include <boost/type_traits/is_convertible.hpp> struct grill { template<typename U> grill (U) {} }; template<typename T> struct bar { template<typename U> bar (U, typename boost::is_convertible<U,T>::type* = 0) {} }; void foo() { typedef bar<grill> data_type; boost::optional<data_type> opt; boost::optional<data_type> opt2(opt); // this line (void)opt2; } Here are the error messages (I apologize for the long lines, I shortened them as much as possible by truncating the header paths): type_traits/is_convertible.hpp: In instantiation of ‘const bool boost::detail::is_convertible_basic_impl<boost::optional_detail::optional_base<bar<grill> >&, grill>::value’: type_traits/is_convertible.hpp:329: instantiated from ‘const bool boost::detail::is_convertible_impl<boost::optional_detail::optional_base<bar<grill> >, grill>::value’ type_traits/is_convertible.hpp:452: instantiated from ‘boost::is_convertible<boost::optional_detail::optional_base<bar<grill> >, grill>’ optional/optional.hpp:604: instantiated from ‘boost::optional<T>::optional(const boost::optional<T>&) [with T = bar<grill>]’ optional.cpp:25: instantiated from here optional/optional.hpp:285: error: ‘boost::optional_detail::optional_base<T>::optional_base(const boost::optional_detail::optional_base<T>&) [with T = bar<grill>]’ is protected type_traits/is_convertible.hpp:170: error: within this context type_traits/is_convertible.hpp:170: error: initializing argument 1 of ‘grill::grill(U) [with U = boost::optional_detail::optional_base<bar<grill> >]’ optional/optional.hpp:308: error: ‘boost::optional_detail::optional_base<T>::~optional_base() [with T = bar<grill>]’ is protected type_traits/is_convertible.hpp:170: error: within this context This reproduction case is distilled from a real world example (not my code) where bar=boost::fusion::vector1 and grill=boost::function<void()> The code compiles fine using the same compiler and Boost 1.44. Any ideas on the root of the problem? Thanks in advance! Jon

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Re: [Boost-users] [CMake] link error in Visual Studio when using boost from CMake
by Alain Leblanc 30 Apr '12

30 Apr '12

Don't have much experience with boost in combination with cmake, but don't you still need to add the boost libraries in a target_link_libraries() command? (Or whatever command is usedbto indicate the libraries to link with). A On Apr 30, 2012 2:49 PM, "Hui Wang" <huiwang8921(a)gmail.com> wrote: > Hello, > > I'm using CMake generated Visual Studio solution, and I added boost with > find_package(Boost), > before that I used commands: set(Boost_USE_STATIC_LIBS > ON) set(Boost_USE_MULTITHREADED ON) set(Boost_USE_STATIC_RUNTIME OFF) > after that I used > commands: include_directories(${Boost_INCLUDE_DIR}) add_executable( > MyProject src/main.cpp) > > Because automatic linking is used on Visual Studio when including Boost, > and it typically use static libraries, I try not to conflict with that. But > I get the error: > LINK : fatal error LNK1104: cannot open file > 'libboost_thread-vc100-mt-gd-1_47.lib' > > I installed pre-compiled binary Boost with the installer provided by > BoostPro Computing, and I checked to find that I do have > libboost_thread-vc100-mt-gd-1_47.lib, libboost_thread-vc100-mt-s-1_47.lib > libboost_thread-vc100-mt-sgd-1_47.lib libboost_thread-vc100-mt-1_47.lib > in C:\Program Files\boost\boost_1_47\lib > > I also output messages to find that > Boost_FOUND=TRUE Boost_LIBRARY_DIRS=C:/Program > Files/boost/boost_1_47/lib Boost_INCLUDE_DIRS=C:/Program > Files/boost/boost_1_47 > > So I'm confused why it has the link error. I tried with dynamically > linking too, it can't find the .dll files at runtime either, but again they > exist right there in the directory I installed boost. Could anyone help me > understand where the problem is? > > Thanks! > -- > Sophie Wang > www.sophiehuiwang.com > > > -- > > Powered by www.kitware.com > > Visit other Kitware open-source projects at > http://www.kitware.com/opensource/opensource.html > > Please keep messages on-topic and check the CMake FAQ at: > http://www.cmake.org/Wiki/CMake_FAQ > > Follow this link to subscribe/unsubscribe: > http://www.cmake.org/mailman/listinfo/cmake >

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catch serial port events
by jellad tarek 30 Apr '12

30 Apr '12

hello can i detect a change in pin cts of com1 (in real time) and callback a function with to boost library???? thank you

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