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[Regex] Search Substring with paranthesis
by Subhash Nagre 15 Mar '11

15 Mar '11

Hello, I have a string "(123) Hello" and I want to seach String (123) using boost::regex, Also I needed to do a full word search, so I added \b in the end. Here is my code std::string searchWord = "(123)"; searchWord += "\\" + "b"; // Step 1 boost::regex expression; expression.assign(searchWord); std::string completeStr = "(123) Hello (123)"; std::string::const_iterator start = completeStr.begin(); std::string::const_iterator end = completeStr.end(); boost::smatch what; while (boost::regex_search(start, end, what, expression)) { int32 foundPos = what.position(); int32 foundLen = what.length(); std::string foundString(start + foundPos, start + foundPos + foundLen); //This foundStr is 123, beacuse it finds a metacharacter in the seach expression // Perform some task with foundString start += foundPos + foundLen; } How Can I get (123) back and foundPos and foundLen as 0 and 5 respetively. I tried creating my search expression as /(123/), but it didn't worked. Also if I don't add \b in the search expression in Step 1, even in that case the foundStr is 123 but in that case, the match will be true even for (1234), which I don't want. I want to find full words only. Is there is any flag in boost::regex which can help me out or how can I perform my task. Thanks in advance Subhash

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[1.46.1] Boost 1.46.1 Release available
by Beman Dawes 15 Mar '11

15 Mar '11

Release 1.46.1 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This is a bug fix release that is otherwise the same as 1.46.0. For details, including download links, see http://www.boost.org/users/news/version_1_46_1 The release can also be downloaded directly from SourceForge. See http://sourceforge.net/projects/boost/files/ To install this release on your system, see http://www.boost.org/doc/libs/release/more/getting_started/index.html Thanks, --The Boost release team Beman Dawes Daniel James Eric Niebler Rene Rivera Vladimir Prus

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[StateChart] pass objectpointer to FSM?
by Bernt-Johan Bergshaven 15 Mar '11

15 Mar '11

Hello, first; thank you for an excellent library collection. I recently discovered it, and I'm impressed! My question: How can I pass a pointer to an object into the state machine? I want to use my state machine to control a real-life elevator. All the functions for controlling this elevator is inside class Elevator; I.e: myElevator->startEngine(UP); I've tried different approaches as you might see in my attached code, but I keep getting this error: statemachine: ../boost/boost/cast.hpp:97: Target boost::polymorphic_downcast(Source*) [with Target = ElevatorSM*, Source = boost::statechart::state_machine<ElevatorSM, ElevatorActive>]: Assertion `dynamic_cast<Target>(x) == x' failed. Aborted h-file: http://codepad.org/i3rAjT1p cpp-file: http://codepad.org/TpaWluCz Appreciate your help, Bernt-Johan Bergshaven, Norway

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how to create a tuple from an mpl sequence?
by Peter Foelsche 15 Mar '11

15 Mar '11

I've got some mpl sequence from which I want to create a tuple. Anybody any clue? I also looked into fusion (why is there so much overlap to mpl?) but did not find anything. Tried fusion::result_of::push_back without much success. Tried fusion::vector with fusion::result_of::push_back . Does this functionality exist? Peter

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[uBLAS] Identity Matrix Constructor vs Resize
by Ryan 14 Mar '11

14 Mar '11

I have an identity matrix that when initialized with the constructor I don't get an error. If I do a default construction and then resize the matrix I get a runtime error. I'm not sure the difference. Could someone enlighten me? Ryan using namespace boost::numeric::ublas; template<typename matrixT> matrix_range<matrixT> topleft (matrixT & M) { return subrange(M, 0, 3, 0, 3); } int main(int, char const* []) { vector<double> initial(3); initial[0] = 10; initial[0] = 100; initial[0] = 2; //I realize that "matrix<double> P(zero_matrix<double>(9,9));" would do the same thing as below. //This is extracted from a class and the constructor needs to to this. matrix<double> P; //This is a class variable P.resize(9,9); //This happens in the constructor P.clear(); //This happens in the constructor //The following runs without errors //identity_matrix<double> identity(3); //This causes a run time error. identity_matrix<double> identity; identity.resize(3); topleft(P) = initial[0] * identity; return 0; }

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backporting filesystem v3
by Arash Abghari 14 Mar '11

14 Mar '11

Hi, I wonder if it is possible to backport filesystem v3 to 1.40 by replacing source folder from 1.46. Thanks Arash

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boost::mutex over a socket
by Marco Piacentini 14 Mar '11

14 Mar '11

Hi guys...I've 2 thread and I would like that one of these performs a synchronous read, menawhile the other performs a synchrounous write...adn obviously they share the same socket.....the signature of the functions are the following: length=boost::asio::read(socket_,boost::asio::buffer(msg,sizeof(msg)), ec); boost::asio::write(socket_,boost::asio::buffer(msgToSend,sizeof(msgToSend))); socket_ is a private field of the classe Server. How can I use the mutex to perform concurrently and safetly these operations? Thanks..

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[GIL] Compilation times
by Germán Diago 14 Mar '11

14 Mar '11

Hello. I'm using g++-4.4 with boost libraries and they're great. However, I have to use some image manipulation algorithms for two types of images (rgb8 and gray). I'm using it successfully, however, compilation times have increased a lot: I use apply_operation and any_image and any_image_view with two types each (rgb8 and gray8) Is there a way to decrease compile times? Thanks in advance.

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Small logic::tribool riddle
by Thomas Jarosch 14 Mar '11

14 Mar '11

Hello, here's a small boost::logic::tribool riddle: -<snip>------------------------------------- #include <iostream> #include <boost/logic/tribool.hpp> int main(void) { boost::logic::tribool foo(boost::logic::indeterminate); if (foo != true) { std::cout << "reached1\n"; } if (foo == boost::logic::indeterminate) { std::cout << "reached2\n"; } return 0; } -<snap>------------------------------------- Try to determine the printed result without looking at the boost::logic::tribool implementation / documentation. Intuitive? A coworker just shot himself in the foot... Best regards, Thomas Jarosch

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Re: [Boost-users] Boost-users Digest, Vol 2660, Issue 1
by Leon Sit 14 Mar '11

14 Mar '11

> > ---------- Forwarded message ---------- > From: Joel Falcou <joel.falcou(a)lri.fr> > To: boost-users(a)lists.boost.org > Date: Sat, 12 Mar 2011 08:24:53 +0100 > Subject: Re: [Boost-users] [proto] Object got sliced when passed by > reference > I just compiled your smaple using g++-4.5 and i got: > > logical_and( > logical_or( > terminal(4baseI2F1E) > , terminal(4baseI2F2E) > ) > , terminal(4baseI2F3E) > ) > hodqhoqw > 0 > > Why is I think the correct answer. So this is tied to some MSVC specific > behavior, i guess mayeb on how the terminal< base<_> const &> is matched. > matching terminal< base<_> > should be enough I think no ? Could you try ? > > HTH > > > > Thats what I did at the very beginning but fail. So I moved on to try const& but still fail. Before I started using proto, I hand-craft some overloaded operator to return the expression object too but failed with the same error. This makes me think that it is a compiler bug too. Should I try something else too?

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