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[mutex] Error in static method
by Daniele Barzotti 29 Mar '10

29 Mar '10

Hi, I have a class which defines a static callback: -------------------------------------------------------------- class CDeviceManager { private: struct TCallbackUserData { CDeviceManager* ptrThis; INT CurrentApi; }; // Since the callback is static, I need this struct to pass data TCallbackUserData CBUserData_; boost::mutex Mutex_; }; INT CDeviceManager::audio_callback(void *outputBuffer, void *inputBuffer, UINT nBufferFrames, double streamTime, RtAudioStreamStatus status, void *userData ) { CDeviceManager* This = 0; TCallbackUserData* UserData = (TCallbackUserData*)userData; This = UserData->ptrThis; // Used if the audio device is opened with simultaneous API boost::lock_guard<boost::mutex> lock(This->Mutex_); } -------------------------------------------------------------- But on compiling I get: 1>d:\lib\boost_1_42_0\boost\thread\win32\mutex.hpp(38) : error C2248: 'boost::noncopyable_::noncopyable::operator =' : cannot access private member declared in class 'boost::noncopyable_::noncopyable' 1> d:\lib\boost_1_42_0\boost\noncopyable.hpp(28) : see declaration of 'boost::noncopyable_::noncopyable::operator =' 1> d:\lib\boost_1_42_0\boost\noncopyable.hpp(22) : see declaration of 'boost::noncopyable_::noncopyable' 1> This diagnostic occurred in the compiler generated function 'boost::mutex &boost::mutex::operator =(const boost::mutex &)' I know that the mutex is noncopyable, but I use this many times. It depends by the 'static' method? Regards, Daniele.

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[mpl] Constant time mpl::contains<mpl::set>
by strasser＠uni-bremen.de 29 Mar '10

29 Mar '10

Hi, I'd like to be able to query if a MPL Sequence contains a certain type, aka mpl::contains. But mpl::contains is documented to always have linear complexity, even for mpl::set's. How can you differentiate between types of MPL Sequences, so you can use mpl::at for sets and mpl::contains for vectors? MPL itself seems to do this by template specialization, e.g. for mpl::at, which is overloaded. But template specialization relies on MPL implementation details, is there a way to detect any type that models an associative sequence? I can't find something like mpl::is_set nor a tag to dispatch with in the AssociativeSequence concept. Thank you, Stefan

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Compiling with Sun C++ 5.8 Patch 121018-11 2007/05/02
by John Ky 29 Mar '10

29 Mar '10

Hi all, Has anyone had any success with compiling boost 1.42.0 with Sun C++ 5.8 Patch 121018-11 2007/05/02? Cheers, -John

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[serialization] Are there libraries to deserialize XML for any scripting languages?
by Martin Muggli 29 Mar '10

29 Mar '10

Hi, I'd like to be able to work with the data serialized using the xml_oarchive serializer in a scripting language for rapid development of a debugging/diagnostic tool. It seems conceivable a library could construct a native representation of a C++ object model. I would think it could do this using just the serialized XML since most scripting languages allow dynamic creation/modification of classes and objects. I've searched the web for such a thing, but didn't stumble across anything. Can anyone point me toward any work that's been done in this area? A possible alternative that comes to mind is to use py++ to generate Python/boost.Python bindings to the original C++ classes and just use the boost::serilization XML deserializer, but I'm concerned getting all that working will offset the time savings of a scripting language. Thanks in advance, Martin This email and any attachments are intended for the sole use of the named recipient(s) and contain(s) confidential information that may be proprietary, privileged or copyrighted under applicable law. If you are not the intended recipient, do not read, copy, or forward this email message or any attachments. Delete this email message and any attachments immediately.

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How to write an IP address parser with actions to fill-in a simple struct?
by Lars Rohwedder 29 Mar '10

29 Mar '10

I have a rule like this: rule<> IP_Parser = int_p>>'.'>>int_p >>'.'>>int_p >>'.'>>int_p >> !( ('/'>>int_p)|(':'>>int_p)); Now I want to extend it that the user can use that parser to fill a simple struct: struct IP_address { std::string host; int port; int netmask; }; and use it this way: IP_address src; rule<> Source = str_p("source") >> +space_p >> IP_Parser(src) >> *space_p >> ';'; Any ideas how to do that with the old boost::spirit (boost version 1.35)? Lars R.

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A question on the preciseness of the double used in MTL. Can anyone with kindness help me?
by fmingu 29 Mar '10

29 Mar '10

I am using MTL(Matrix Template Library) for Matrix computing in Dev-C++ 4.9.8.0 and updated the gcc version from 3.2 to 4.4.1 by installing tdm-mingw-1.908.0-4.4.1-2 and the boost version is 1.37.0. The system is Windows xp The sample code is : #include <boost/numeric/mtl/mtl.hpp> #include "boost/random/normal_distribution.hpp" #include <boost/random.hpp> #include <boost/random/uniform_real.hpp> int main(int argc, char* argv[]) { using namespace mtl; using namespace mtl::matrix; const unsigned n= 5; dense2D<double> A(n, n), B(n, n); morton_dense<double, doppled_64_row_mask> C(n, n), D(n, n); dense2D<double> F(n, n), E(n, n); hessian_setup(A, 3.0); hessian_setup(B, 1.0); hessian_setup(C, 2.0); hessian_setup(D, 11.0); B(1,1)=9.9999; .......................... std::cout << "The matrices are: B=\n" << B <<"\n"; std::cout << "The result is " <<1.0/3.0 <<"\n"; ……………………. But the result is shown that B(1,1) is 10, and 1.0/3.0 is 0.33. How can I get the highest precision of the type double and dense2D<double> for scientific computation? The same question occurred in random number generation in boost random library. Can anyone with kindness help me?

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synchronization problem
by alev mutlu 28 Mar '10

28 Mar '10

Hi all, For the following code I want to stop early completing processes and wait for the others at the point with (world.barrier)(); statement. But the problem is stop- and stop+ do interleave. Am I doing something wrong with the synchronization, or there is something wrong with my code? if (world.rank() == MASTER){ m_mySize = n / world.size() + n % world.size(); w_mySize = n / world.size(); for(int p = 1; p < world.size(); p++){ world.send(p, 1, w_mySize); world.send(p, 2, n); } relMyValues = new possibleClause[w_mySize]; scatter(world, pC, relMyValues, w_mySize, 0); } else{ world.recv(0, 1, w_mySize); relMyValues = new possibleClause[w_mySize]; scatter(world, pC, relMyValues, w_mySize, 0); } for(i = 0; i < w_mySize; i++){ //do something } cout << world.rank() << " stop - " << world.rank() << endl; (world.barrier)(); cout << world.rank() << " stop + " << world.rank() << endl; if (world.rank() == MASTER){ relAllValues = new possibleClause[n - n % world.size()]; gather(world, relMyValues, w_mySize, relAllValues, 0); } else{ world.recv(0, 2, n); gather(world, relMyValues, w_mySize, relAllValues, 0); }

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new user: error: 'std::tr1' has not been declared
by Juan Vesa 28 Mar '10

28 Mar '10

hello, i'm a brand new user to boost, with xcode 2.4.1, os x 10.4.11 (intel), i686-apple-darwin8-gcc-4.0.1 i'm getting some errors trying to use a library (http:// www.cs.kuleuven.ac.be/~ares/libply/) which uses boost. however i am stuck at the error: error: 'std::tr1' has not been declared doing ./config from boot_root/libs/config, i get the following output related to tr1: checking std::tr1::array... no checking std::tr1::bind... no checking std::complex overloads... no checking std::complex inverse trig functions... no checking std::tr1::function... no checking std::tr1::hash... no checking std::tr1::mem_fn... no checking std::tr1::random... no checking std::tr1::reference_wrapper... no checking std::tr1::regex... no checking std::tr1::result_of... no checking std::tr1::shared_ptr... no checking std::tr1::tuple... no checking std::tr1::type_traits... no checking std::tr1::unordered_map... no checking std::tr1::unordered_set... no checking std::tr1::utility... no so, how can i enable the successful use of the std::tr1 libraries available with boost? regards,

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is it safe to do this with signals?
by Germán Diago 28 Mar '10

28 Mar '10

Hello. I have a class like this: class MyClass : public trackable { unique_ptr<void ()> Signal1; ... }; This class is movable. So I move everything when transferring the internals. I would like to know if this is safe to do in the presence of a trackable base class or if when the moved instance is destroyed this could cause problems. Thanks.

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overloaded const/non-const functions and bind
by Andrej van der Zee 28 Mar '10

28 Mar '10

Hi, I want to use a function in bind that has a const and non-const version named Node::get_parent. I am using the following expression: NodeSet nodes_whitespace = doc->get_root_node()->find("//text()[normalize-space()='']"); for_each(nodes_whitespace.begin(), nodes_whitespace.end(), bind(&Node::remove_child, bind(&Node::get_parent, _1))); I get the obvious error: ../parsers-refact/trans-full/main.cpp: In function ‘void remove_whitespace_nodes(xmlpp::Document*)’: ../parsers-refact/trans-full/main.cpp:56: error: call of overloaded ‘bind(<unresolved overloaded function type>, boost::arg<1>&)’ is ambiguous /usr/local/include/boost/bind/bind_mf_cc.hpp:20: note: candidates are: boost::_bi::bind_t<R, boost::_mfi::mf0<R, T>, typename boost::_bi::list_av_1<A1>::type> boost::bind(R (T::*)(), A1) [with R = xmlpp::Element*, T = xmlpp::Node, A1 = boost::arg<1>] /usr/local/include/boost/bind/bind_mf_cc.hpp:30: note: boost::_bi::bind_t<R, boost::_mfi::cmf0<R, T>, typename boost::_bi::list_av_1<A1>::type> boost::bind(R (T::*)()const, A1) [with R = const xmlpp::Element*, T = xmlpp::Node, A1 = boost::arg<1>] Is there a way to get the const_iterator? Or is there any other solution? Thank you, Andrej

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