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how to make fusion::pair less-than-comparable?
by Zeljko Vrba 22 Aug '08

22 Aug '08

Related to my previous question: fusion::map is a sequence and instances of it could be directly compared with operator < , thus vectors of instances also sorted if fusion::pair supported relational operators other than == and != (which it doesn't). So, two questions: 1. What is the recommended way of defining operator< for particular pair instances (e.g. for pair<net, int>) ? 2. An explanation of why doesn't fusion::pair define at least operator< would be welcome. Thanks. (Yes, I know, I can pass an explicit predicate to std::sort.. )

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Re: [Boost-users] Boost serialization..
by Sangeeta Singh 22 Aug '08

22 Aug '08

Hi, Thanks for the pointer. Is the string serialization for 64 bit and 32 bit library different as the string being serialized using 64bit version can not be read using 32 bit version. Thanks, Sangeeta Message: 1 Date: Thu, 21 Aug 2008 13:10:26 -0800 From: "Robert Ramey" <ramey(a)rrsd.com> Subject: Re: [Boost-users] Boost serialization.. To: boost-users(a)lists.boost.org Message-ID: <g8ki3p$iv7$2(a)ger.gmane.org> Content-Type: text/plain; charset="iso-8859-1" THe library includes a portable_binary archive as a demo. There are also other versions of this in boost downloads. Robert Ramey "Sangeeta Singh" <singhs(a)yahoo-inc.com> wrote in message news:228C81146E16054AA04E582D4B8C34CD96C888@SNV-EXVS08.ds.corp.yahoo.com ... Hi, I have following requirement Application doing the object serialization (binary stream with char trait) uses 64 bit boost serialization version Application deserializing the object uses 32 bit boost serialization version Both are incompatible. Is there a boost serialization library available that works for both 64 and 32 bit m/c or is there any other way that I can achieve this. Thanks, Sangeeta

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Serialization of derived classes with boost 1.34.1
by Hansi 22 Aug '08

22 Aug '08

Hello, I have a problem to serialize a derived class. In some classes I use a shared_ptr<A> which acts as a interface for some other classes. Til now I had the implementation in the header and it worked fine with the BOOST_CLASS_EXPORT(B) declaration after at the end of the header file where B was defined. For performance reason (compile time) I have moved the serialization code from the header file (there is only the declaration) to the .cpp file (now I use also only the polymorphic_binary_archive). There I have also the declaration for the polymorphic_binary_archive template void B::serialize(boost::archive::polymorphic_iarchive& ar, const unsigned int file_version); template void B::serialize(boost::archive::polymorphic_oarchive& ar, const unsigned int file_version); After linking I have now some linker errors. First for the class B which is derived from A and for the class A. All linker errors use the binary_archive. If I declare the "BOOST_CLASS_EXPORT(B)" at the end in the .cpp file I get only an linker error for class A. How I can solve this? Best regards Hansjörg

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Re: [Boost-users] Fusion: some concrete questions about maps and vectors
by Zeljko Vrba 22 Aug '08

22 Aug '08

On Thu, Aug 21, 2008 at 09:39:01PM -0400, Daryle Walker wrote: > > Are the two vectors supposed to represent the same relation? If so, > could Boost's BiMap help? > No, they represent the two halves of a symmetric relation.

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Fusion: some concrete questions about maps and vectors
by Zeljko Vrba 22 Aug '08

22 Aug '08

I'm operating on two vectors of pairs of numbers, currently represented by std::pair<unsigned, unsigned>. The first vector is a list of (net,pin) pairs, while the second vector is a list of (pin, net) pairs. In order to raise a bit the understandability / abstraction level of my code, I think that it'd be nice to be able to write at_key<pin>(x) and at_key<net>(x) instead of x.first or using tie(). Looking at fusion manual, it seems that of all the containers, map suits the purpose: struct pin; struct net; First question: are Map1 and Map2 different types? typedef map<pair<pin, unsigned>, pair<net, unsigned> > Map1; typedef map<pair<net, unsigned>, pair<pin, unsigned> > Map2; According to a simple test program that I wrote, which basically boils down to Map m1; Map m2; m1 = m2; they, are different because the compilation fails. Hmm, so far, so good. Second question: some algorithms are common both for both types, e.g. sort, where I want to have lexicographical comparison between the elements. Is it possible to somehow transform Map1 and Map2 so that they both appear as typedef vector<unsigned, unsigned> > Pair with proper lexicographical ordering? OK, there are conversion metafunctions, but I want something more; the following code std::vector<Map1> m; std::sort(m.begin(), m.end()); should process vector elements (Map1s) _as_if_ they were Pairs or ordinary std::pair. I see there are conversion metafunctions defined in documentation, but I don't know how to use them to convert std::vector<Map1> to std::vector<Pair> when giving m as argument to sort() [if this is possible at all]. Sorry for the long post and if it is somewhat vague. === (I could probably avoid using fusion by manually defining two different struct types, each holding pin/net members and defining operator< for each, but I want to finally get my hands dirty with fusion on a concrete, not too complex problem that I'm facing right now.)

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Boost-users] [python]How to pass C++ object reference to python code?
by Neil Fang 22 Aug '08

22 Aug '08

I'm trying embedding python using boost::python. Just as the same way as the boost::python quick start "embedding.cpp". I have a C++ base class, with a virtual function do something on another C++ object: struct MyClass { void printThis() { std::cout << "0x" << this << std::endl; } }; // An abstract base class class Base : public boost::noncopyable { public: virtual ~Base() {}; virtual void printMyClass(MyClass& myObj) = 0; }; Than, I want to write some Python derived class code: "from embedded_hello import * \n" "class PythonDerived(Base): \n" " def printMyClass(self, myObj): \n" " myObj.printThis() \n" But I found that the "myObj" passed to python code is another obj, not the object created in C++ code. How can use the object created in C++ object rather than a copyed object? Thanks! The full code list below, which is modified form boost::python example. // Copyright Stefan Seefeld 2005. // Distributed under the Boost Software License, Version 1.0. (See // accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) #include <boost/python.hpp> #include <boost/detail/lightweight_test.hpp> #include <iostream> namespace python = boost::python; struct MyClass { void printThis() { std::cout << "0x" << this << std::endl; } }; // An abstract base class class Base : public boost::noncopyable { public: virtual ~Base() {}; virtual std::string hello() = 0; virtual void printMyClass(MyClass& myObj) = 0; }; // C++ derived class class CppDerived : public Base { public: virtual ~CppDerived() {} virtual std::string hello() { return "Hello from C++!";} virtual void printMyClass(MyClass& myObj) { myObj.printThis(); } }; // Familiar Boost.Python wrapper class for Base struct BaseWrap : Base, python::wrapper<Base> { virtual void printMyClass(MyClass& myObj) { this->get_override("printMyClass")(myObj); } virtual std::string hello() { #if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) // workaround for VC++ 6.x or 7.0, see // http://boost.org/libs/python/doc/tutorial/doc/html/python/exposing.html#pyt… return python::call<std::string>(this->get_override("hello").ptr()); #else return this->get_override("hello")(); #endif } }; // Pack the Base class wrapper into a module BOOST_PYTHON_MODULE(embedded_hello) { python::class_<BaseWrap, boost::noncopyable> base("Base"); python::class_<MyClass>("MyClass") .def("printThis", &MyClass::printThis) ; } void exec_test() { std::cout << "registering extension module embedded_hello..." << std::endl; // Register the module with the interpreter if (PyImport_AppendInittab("embedded_hello", initembedded_hello) == -1) throw std::runtime_error("Failed to add embedded_hello to the interpreter's " "builtin modules"); std::cout << "defining Python class derived from Base..." << std::endl; // Retrieve the main module python::object main = python::import("__main__"); // Retrieve the main module's namespace python::object global(main.attr("__dict__")); // Define the derived class in Python. python::object result = python::exec( "from embedded_hello import * \n" "class PythonDerived(Base): \n" " def hello(self): \n" " return 'Hello from Python!' \n" " def printMyClass(self, myObj): \n" " myObj.printThis() \n" , global, global); python::object PythonDerived = global["PythonDerived"]; MyClass myObj; // Creating and using instances of the C++ class is as easy as always. CppDerived cpp; BOOST_TEST(cpp.hello() == "Hello from C++!"); cpp.printMyClass(myObj); std::cout << "testing derived class from C++..." << std::endl; // But now creating and using instances of the Python class is almost // as easy! python::object py_base = PythonDerived(); Base& py = python::extract<Base&>(py_base) BOOST_EXTRACT_WORKAROUND; // Make sure the right 'hello' method is called. BOOST_TEST(py.hello() == "Hello from Python!"); py.printMyClass(myObj); std::cout << "success!" << std::endl; } void exec_file_test(std::string const &script) { std::cout << "running file " << script << "..." << std::endl; // Run a python script in an empty environment. python::dict global; python::object result = python::exec_file(script.c_str(), global, global); // Extract an object the script stored in the global dictionary. BOOST_TEST(python::extract<int>(global["number"]) == 42); std::cout << "success!" << std::endl; } void exec_test_error() { std::cout << "intentionally causing a python exception..." << std::endl; // Execute a statement that raises a python exception. python::dict global; python::object result = python::exec("print unknown \n", global, global); std::cout << "Oops! This statement should be skipped due to an exception" << std::endl; } int main(int argc, char **argv) { //BOOST_TEST(argc == 2); //std::string script = argv[1]; // Initialize the interpreter Py_Initialize(); bool error_expected = false; if ( python::handle_exception(exec_test) ) { if (PyErr_Occurred()) { if (!error_expected) BOOST_ERROR("Python Error detected"); PyErr_Print(); } else { BOOST_ERROR("A C++ exception was thrown for which " "there was no exception translator registered."); } } std::cin.get(); // Boost.Python doesn't support Py_Finalize yet, so don't call it! return boost::report_errors(); }

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boost.python - undefined symbol error
by antonyc 22 Aug '08

22 Aug '08

I've just started this morning with boost::python and have been struggling all day to get the basic http://www.boost.org/doc/libs/1_35_0/libs/python/doc/tutorial/doc/html/pyth… 'exposing classes' doc/tutorial: to link correctly under gcc 4.1.2. I would greatly appreciate any help as I'm sure it's probably something simple and I'm pretty much at a loss at the moment. So the source file compiles and the shared object appears to link ok however when I try and import the module, python reports the following missing symbol: ImportError: /test/BoostPython/hello.so: undefined symbol: _ZN5boost6python9converter8registry6insertEPFPvP7_objectEPFvS5_PNS1_30rvalue_from_python_stage1_dataEENS0_9type_infoE de-mangled courtesy of c++filt: boost::python::converter::registry::insert(void* (*)(_object*), void (*)(_object*, boost::python::converter::rvalue_from_python_stage1_data*), boost::python::type_info) Indeed a search through the boost.python headers yields no such function prototype. Nor does searching the symbols defined in libboost_python-gcc41-mt.so. The closest match I can find in libboost_python-gcc41-mt.so is: boost::python::converter::registry::insert(void* (*)(_object*), void (*)(_object*, boost::python::converter::rvalue_from_python_stage1_data*), boost::python::type_info, _typeobject const* (*)()) which appears to match the following function in python/converter/registry.hpp: // Insert an rvalue from_python converter BOOST_PYTHON_DECL void insert( convertible_function , constructor_function , type_info , PyTypeObject const* (*expected_pytype)() = 0 ); Beyond that I'm pretty much stuck. Thanks in advance to anyone who can help me out! antony /*------------------- hello.cpp -------------------*/ #include <string> struct World { void set(std::string msg) { this->msg = msg; } std::string greet() { return msg; } std::string msg; }; #include <boost/python.hpp> using namespace boost::python; BOOST_PYTHON_MODULE(hello) { class_<World>("World") .def("greet", &World::greet) .def("set", &World::set) ; } /*-----------------------------------------------------------*/ g++ -c -g -Wall -fPIC -pipe -DBOOST_PYTHON_MAX_ARITY=20 -I. -I/usr/local/include -I/usr/local/include/python2.5 hello.cpp g++ -shared -o hello.so hello.o -L/usr/local/lib -lpython2.5 -lboost_python-gcc41-mt -- View this message in context: http://www.nabble.com/boost.python---undefined-symbol-error-tp19054023p1905… Sent from the Boost - Users mailing list archive at Nabble.com.

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re: Wrapping a library
by Alan Baljeu 21 Aug '08

21 Aug '08

>> I have this library (one class with 700 methods) I want to wrap all the calls, so I can log the calls and do other stuff. Using emacs macros and stuff, I >>can create a proxy class which has the same signature, but each method calls a C macro which calls the original class method, and does other stuff. > A class or a namespace? A document class. Yes it's huge. >> >> I'm thinking there must be a better way. I'm thinking BOOST_PP library could abstract the above macros into something concise. However, the >> library is intimidating. There are lots of features, and I'm not clear on how I should get started. >For ad hoc code generation, I usually end up with awk and sed. I just did this wrapping >thing with a java class definition ( no actual source code) and could pretty much use lynx to render the javadoc html, extract >method signatures, and use awk to generate methods with sed and finally >vi to touch stuff up. The generated class contained an instance of the original class that >was simply called in each generated method after my custion code,if any, executed. >I wasn't just interested in wrapping as I also made a fake version for >unsupported operations. That does seem to be a good approach. Thanks for the idea. __________________________________________________________________ Yahoo! Canada Toolbar: Search from anywhere on the web, and bookmark your favourite sites. Download it now at http://ca.toolbar.yahoo.com.

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Boost serialization..
by Sangeeta Singh 21 Aug '08

21 Aug '08

Hi, I have following requirement Application doing the object serialization (binary stream with char trait) uses 64 bit boost serialization version Application deserializing the object uses 32 bit boost serialization version Both are incompatible. Is there a boost serialization library available that works for both 64 and 32 bit m/c or is there any other way that I can achieve this. Thanks, Sangeeta

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Decoding hex stream of bytes to binary form
by Mateusz Loskot 21 Aug '08

21 Aug '08

Hi, I've a small function (see below) to convert hex encoded stream of bytes to binary stream. My question is, could anyone suggest equivalent function but implemented with help of Boost libraries? I don't have any particular goal or requirement like better performance, simpler implementation, etc. I'm just curious what Boost components I can use to achieve this kind of tasks. I've scanned the archives but there seem to be not much on encoding/decoding hex string, just: http://lists.boost.org/boost-users/2007/11/32269.php // hex-to-bin function #include <sstream> #include <string> #include <vector> typedef std::vector<unsigned char> ewkb_t; // hexstr [in] - string with hex encoded bytes // bytes [out] - output in binary form void hex_to_bin(std::string const& hexstr, ewkb_t bytes) { bytes.clear(); for(std::string::size_type i = 0; i < hexstr.size() / 2; ++i) { std::istringstream iss(hexstr.substr(i * 2, 2)); unsigned int n; iss >> std::hex >> n; bytes.push_back(static_cast<unsigned char>(n)); } } Best regards, -- Mateusz Loskot, http://mateusz.loskot.net Charter Member of OSGeo, http://osgeo.org

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Wrapping a library
by Alan Baljeu 21 Aug '08

21 Aug '08

I have this library (one class with 700 methods) I want to wrap all the calls, so I can log the calls and do other stuff. Using emacs macros and stuff, I can create a proxy class which has the same signature, but each method calls a C macro which calls the original class method, and does other stuff. For example: void logfunc(char *func) const { OutputDebugStringA(func); } void logarg(int a) // overload for each type of parameter { CString x; x.Format(L"%d", a); OutputDebugString(x); } ULONG GetID(const CKSEntity &pEntity) const { return proxy1(GetID, pEntity); } // repeat for all 700 methods. // Repeat these macros for every count of arg between 0 and 24. #define proxy10(Func, Arg1,Arg2,Arg3,Arg4,Arg5,Arg6,Arg7,Arg8,Arg9,Arg10) \ ( log10(#Func, Arg1,Arg2,Arg3,Arg4,Arg5,Arg6,Arg7,Arg8,Arg9,Arg10), \ thePart.Func( Arg1,Arg2,Arg3,Arg4,Arg5,Arg6,Arg7,Arg8,Arg9,Arg10)) #define log10(Func, Arg1,Arg2,Arg3,Arg4,Arg5,Arg6,Arg7,Arg8,Arg9,Arg10) \ log9(Func, Arg1,Arg2,Arg3,Arg4,Arg5,Arg6,Arg7,Arg8,Arg9), logarg(Arg10) #define log0(Func ) \ logfunc(Func) I'm thinking there must be a better way. I'm thinking BOOST_PP library could abstract the above macros into something concise. However, the library is intimidating. There are lots of features, and I'm not clear on how I should get started. __________________________________________________________________ Looking for the perfect gift? Give the gift of Flickr! http://www.flickr.com/gift/

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[asio] wacky behavior in async_write/async_read
by n0vicd_c0der 21 Aug '08

21 Aug '08

Hi, I am trying to code a simple POP3S client. I am using the boost::asio sockets and SSL wrapper. Somehow, the output from the async_read_util is directed to the input of the async_write. Not sure if the issue is the memory or the order of calls. Any idea? The code snippet is below, but here is the output of my program first (I replaced the IP with x's) bash# ./main 209.85.199.111 995 foo.bar(a)gmail.com pass_in_plain_text Got RES (66) bytes +OK Gpop ready for requests from xxx.xxx.xxx.xxx c20pf1156691rvf.3 Sent REQ: APOP foo.bar(a)gmail.com pass_in_plain_text Got RES (36) bytes -ERR bad command c20pf1156691rvf.3 Sent REQ: STAT Read failed: End of file Exception: End of file and here is the code snippet #include <cstdio> #include <cstdlib> #include <unistd.h> #include <iostream> #include <boost/bind.hpp> #include <boost/asio.hpp> #include <boost/asio/ssl.hpp> #include <boost/asio/detail/throw_error.hpp> enum { max_length = 8192 }; class client { public: client(boost::asio::io_service& io_service, boost::asio::ssl::context& context, boost::asio::ip::tcp::endpoint& endpoint) : socket_(io_service, context) { //connect to the pop3 server socket_.lowest_layer().async_connect(endpoint, boost::bind(&client::handle_connect, this, boost::asio::placeholders::error)); } ~client() { socket_.lowest_layer().close(); } void handle_connect(const boost::system::error_code& error) { if (!error) { //do the SSL handshake socket_.async_handshake(boost::asio::ssl::stream_base::client, boost::bind(&client::handle_handshake, this, boost::asio::placeholders::error)); } else { std::cerr << "Connection failed: " << error << "\n"; boost::asio::detail::throw_error(error); } } void handle_handshake(const boost::system::error_code& error) { if (error) { std::cerr << "SSL Handshaking failed: " << error << "\n"; boost::asio::detail::throw_error(error); } } void write(std::string buffer) { str_req=buffer; boost::asio::async_write(socket_, boost::asio::buffer(str_req), boost::bind(&client::handle_write, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); } void handle_write(const boost::system::error_code& error, size_t bytes) { if (!error) { std::cout << "Sent REQ: " << str_req <<std::endl; try{ boost::asio::async_read_until(socket_, buff_, "\r\n", boost::bind(&client::handle_read_until, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); }catch(const boost::system::system_error &err){ std::cerr << " code: " << err.code().value() << " :" << err.code().message() << std::endl; } } else { std::cerr << "Write failed: " << error.message() << "\n"; boost::asio::detail::throw_error(error); } } void read() { try{ boost::asio::async_read_until(socket_, buff_, "\r\n", boost::bind(&client::handle_read_until, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); }catch(const boost::system::system_error &err){ std::cerr << " code: " << err.code().value() << " :" << err.code().message() << std::endl; } } void handle_read_until(const boost::system::error_code& error, size_t bytes_transferred) { if (!error) { std::cout << "Got RES (" << bytes_transferred<<") bytes\n"; std::cout << &buff_; std::cout << "\n"; } else { std::cout << "Read failed: " << error.message() << "\n"; boost::asio::detail::throw_error(error); } } private: boost::asio::ssl::stream<boost::asio::ip::tcp::socket> socket_; boost::asio::streambuf buff_; //for receiving std::string str_req; //for sending }; int main(int argc, char* argv[]) { try { if (argc != 5) { std::cerr << "Usage: " << argv[0] << " <host> <port> <user> <pass>\n"; return 1; } boost::asio::io_service io_service; boost::asio::ssl::context ctx(io_service, boost::asio::ssl::context::sslv23); ctx.set_verify_mode(boost::asio::ssl::context::verify_none); boost::asio::ip::tcp::endpoint endpoint( boost::asio::ip::address::from_string(argv[1]), atoi(argv[2])); client c(io_service, ctx, endpoint); io_service.run(); //should execute till handshake completes //read the pop3 greeting io_service.reset(); io_service.post(boost::bind(&client::read,&c)); io_service.run(); //send the authentication command std::string str_cmd="APOP " + std::string(argv[3]) + " " + std::string(argv[4]) +"\r\n"; io_service.reset(); io_service.post(boost::bind(&client::write,&c,str_cmd)); io_service.run(); //get how many messages are in the inbox str_cmd="STAT\r\n"; io_service.reset(); io_service.post(boost::bind(&client::write,&c,str_cmd)); io_service.run(); //quit the pop3 session str_cmd="QUIT\r\n"; io_service.reset(); io_service.post(boost::bind(&client::write,&c,str_cmd)); io_service.run(); } catch (std::exception& e) { std::cerr << "Exception: " << e.what() << "\n"; } return 0; } -- View this message in context: http://www.nabble.com/-asio--wacky-behavior-in-async_write-async_read-tp190… Sent from the Boost - Users mailing list archive at Nabble.com.

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[shared_ptr] Implicit cast shared_ptr<derived> to shared_ptr<base>
by Ruediger Berlich 21 Aug '08

21 Aug '08

Hi there, after making what I then thought was a bad mistake, I discovered that the code below actually works (gcc 4.3.1, OpenSUSE 11 64bit, Boost 1.36). I.e., there is an implicit cast from shared_ptr<derived> to shared_ptr<base> to make it fit the function argument, although both represent different types. Is this intended behaviour (i.e. portable) ? I did not find a corresponding description in the docu. Thanks and Best Regards, Ruediger /**************************************************************************/ #include <iostream> #include <boost/shared_ptr.hpp> class base{ public: virtual ~base(){} virtual void print() const { std::cout << "Hello world from base" << std::endl; } }; class derived :public base { public: void print() const { std::cout << "Hello world from derived" << std::endl; } }; void executeBasePrint(const boost::shared_ptr<base>& base_ptr){ base_ptr->print(); } main(){ boost::shared_ptr<derived> derived_ptr(new derived()); // Results in "Hello world from derived" executeBasePrint(derived_ptr); }

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[filesystem] Bugs in path::append ?
by Sachin Garg 21 Aug '08

21 Aug '08

I have following 3 lines of code, is this usage correct? fs::wpath input_path=somepath; fs::wpath output_path=anotherpath; output_path.append(input_path.begin()+7,input_path.end()); The 3rd line gives following error (using Visual Studio 9.0 and boost 1.35.0) C:\Program Files\boost\boost_1_35_0\boost/filesystem/path.hpp(1058) : error C2664: 'boost::filesystem::detail::is_separator' : cannot convert parameter 1 from 'const std::basic_string<_Elem,_Traits,_Ax>' to 'wchar_t' Looking at the code, it does looks like a problem with path.hpp as is_separator expects a wchar_t parameter but append gives it a wstring (unless there some conversion that should have happened but isn't happening. I temporarily changed *first at line 1058 to first->at(0) and this fixed the error.). And there are other errors too like path.hpp(1068) : error C2677: binary '&&' : no global operator found which takes type 'const std::basic_string<_Elem,_Traits,_Ax>' (or there is no acceptable conversion) This too seems valid as path.hpp:1068 'seems' to assume that *first would be same as first->empty() Is this a known issue fixed in 1.36.0? Seems like some presumed conversions are not happening in path.hpp. Or am I making some super dumb mistake in my usage of append()? Sachin Garg

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Sample code for boost::thread - Timed Lockable mutex ?
by Stéphane Vandenbogaerde 21 Aug '08

21 Aug '08

Hello, I want to use timed lockable mutex in boost::thread, but the usage is not so obvious for a beginner. Would there be anywhere a sample code with this kind og mutex ? I have a code which works with a boost::mutex in a consumer/producer queue (code below). The purpose is to have a maximum waiting delay for waitForNotEmpty(). Thanks. ------------------------------------------------------------------------- template <typename T> class MTBornedQueue { public: .... bool waitForNotEmpty() { if (!m_container.empty()) return true; boost::mutex::scoped_lock lock(m_accessMutex); m_notEmpty.wait(lock, boost::bind(&MTBornedQueue<value_type>::isNotEmpty, this)); return true; } ... private: bool isNotEmpty() const { return m_unread > 0; }; size_type m_unread; container_type m_container; boost::mutex m_accessMutex; boost::condition m_notEmpty; }

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boost::graph issues.
by Raindog 21 Aug '08

21 Aug '08

Hello, This will be the 2nd time I've tried to use boost::graph in a project, the first time I ended up scrapping the effort and using a different graph implementation because of performance reasons, but I was also considering scrapping it for the reasons I have listed here. My newest project will be using much smaller graphs. First, I *want* to use bgl, the problem I have is that it is by far the most complex and difficult to use library I have ever seen. I equate it to something harder than COM using only C. The majority of my difficulties with BGL are related to the extensive use of template magic that does two things for me: makes code impossible to follow and secondly, it makes debugging even more difficult. For example, someone tell me from looking at this, what *values* will actually be passed to astar_search: astar_search (g, s, h, choose_param(get_param(params, graph_visitor), make_astar_visitor(null_visitor())), choose_param(get_param(params, vertex_predecessor), p_map), cost, distance, weight, index_map, color, choose_param(get_param(params, distance_compare_t()), std::less<C>()), choose_param(get_param(params, distance_combine_t()), closed_plus<C>()), choose_param(get_param(params, distance_inf_t()), std::numeric_limits<C>::max BOOST_PREVENT_MACRO_SUBSTITUTION ()), choose_param(get_param(params, distance_zero_t()), C())); } I would be hard pressed to believe that anyone can answer that in a short amount of time even assuming you have memorized all of the template parameters of g and s and even h. On with more issues. One of the biggest issues I have is that the the property_map concept is exceptionally vague and exceedingly difficult to work with. For example, I have created a graph, it's concise typedef: typedef boost::adjacency_list < boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_name_t, Ogre::Vector3>, boost::property<boost::edge_weight3_t, edge_cost> > GraphT; Because of the use of free functions, it's hard to quickly distinguish "get" calls on a property_map from "get" calls on a graph. Additionally, the property_map installation and retrieval to and from a BGL graph is also hard to follow. One might see the following code in the examples directory of bgl: typename property_map<Graph, edge_mycapacity_t>::const_type capacity = get(edge_mycapacity, G); typename property_map<Graph, edge_myflow_t>::const_type flow = get(edge_myflow, G); Where "edge_mycapacity" is an enum; and how exactly enums of the same value can be used to look up different property_maps from the graph is a gaping hole left in the documentation and I still have no idea how it works. Another example is the following: get(vertex_color_t(), g, vertex(2,g)) Here we seem to be left to our imaginations as to how this works. "get" in this case is obviously operating on a graph in this call, but why are we no longer using an enum and instead constructing a temporary "vertex_color_t". Looking at the definition of "get", we see the following: template<typename OutEdgeListS, typename VertexListS, typename DirectedS, typename VertexProperty, typename EdgeProperty, typename GraphProperty, typename EdgeListS, typename T, typename Bundle, typename Key> inline T get(T Bundle::* p, adjacency_list<OutEdgeListS, VertexListS, DirectedS, VertexProperty, EdgeProperty, GraphProperty, EdgeListS> const & g, const Key& key) { return get(get(p, g), key); } Hmm, looks like we'll need to look further. I personally am not knowledgeable enough in template magic to make sense of the majority of the BGL source, for me there are way too many things to keep track of in order to be able to completely follow the code. I can't follow very well 100 character variable declarations. So, for some real questions and to end the rant. 1. What language mechanism is allowing property_maps to be stored and retrieved from an instance of a graph? How does "BOOST_DEF_PROPERTY(edge, index)" work exactly? 2. What *is* the required interface for a property_map? get,put, operator[] of course, but the BGL properties appear to function nothing like the example given in the documentation. 3. Why is using get(p,g) better than using myPropMap.get_from(myGraph) and myGraph.get_property_map(prop_map_type) and myGraph.get_edge(edge_descriptor). What benefit does the chosen method provide? 4. The edge property example contains the following: typedef property<edge_mycapacity_t, int> Cap; typedef property<edge_myflow_t, int, Cap> Flow; typedef adjacency_list<vecS, vecS, bidirectionalS, no_property, Flow> Graph; But accesses the Cap property_map as if it is directly associated with the graph, not a nested property of Flow: typename property_map<Graph, edge_mycapacity_t>::const_type capacity = get(edge_mycapacity, G); Can someone explain how that works in better detail? Thanks, Josh PS. This is the 4rd time i've attempted to send this message as I've not seen it yet appear on the list. The 1st 2 attempts were rejected as I had not yet completed subscription process.

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AIX 5.3 xlC error on ptr_list.hpp
by Gary Fu 21 Aug '08

21 Aug '08

Hi, The simple test program a.cpp below has no problem to compile on linux g++, but failed on AIX xlC compiler. Does any one know if the problem is related to the xlC compiler or the ptr_list.hpp file ? Thanks, Gary 4:43pm 19 Ggfu@sds:~/tmp> xlC_r -I/home_dir/Ggfu/BOOST/boost_1_36_0 -c a.cpp "/home_dir/Ggfu/BOOST/boost_1_36_0/boost/ptr_container/ptr_list.hpp", line 44.9: 1540-0400 (S) "boost::ptr_list::release" has a conflicting declaration. "/home_dir/Ggfu/BOOST/boost_1_36_0/boost/ptr_container/ptr_list.hpp", line 44.9: 1540-0425 (I) "release" is defined on line 44 of "/home_dir/Ggfu/BOOST/boost_1_36_0/boost/ptr_container/ptr_list.hpp". ----------------- a.cpp #include <boost/ptr_container/ptr_list.hpp> boost::ptr_list< std::string > y; int main() { return 0; }

3 2

How to find a sorting permutation
by Zeljko Vrba 21 Aug '08

21 Aug '08

I have a vector of element V that needs to be sorted. I want to also produce a permutation vector P which reflects the element's position in the original vector. P is initialized with identity permutation (P[i] == i). 1st possibility: code my own sorting algorithm, and swap elements of P along with swapping elements of V. This I want to avoid, if at all possible. 2nd possibility: copy elements of V into new vector V' holding pair<T, size_t> and sort that. (pair holds the original element as well as its starting position in the vector, i.e. .second is again initialized to identity permutation.) Drawback: extra space and time spent on copying to V'. 3rd possibility: sort elements of P with less_than doing lookups into V to do its comparison. Drawback: while P holds the correct result, V is left unsorted; I have to do another pass through V and swap elements according to the permutation recorded in P, which is not trivial to do in-place. 4th possibility: I'm not sure whether it'd work: have a separate compilation unit that will provide function sort_vector_of_T, which will take references to V, T and also provide a specialization of std::swap for T which will then also swap elements of P). (Separate compilation unit is needed because I don't want to *globally* redefine std::swap for T) Is there some non-obvious, efficient and elegant way of achieving what I want?

3 3

Implementation question about boost::circular_buffer and allocator
by Peter Barker 21 Aug '08

21 Aug '08

Hello, I've been going through the Boost libraries and encountered boost::circular_buffer. My question is not with the operation of Boost.Circular Buffer as-such, but about how the instantiation of it works without specifying the allocator. The introductory example in the documentation(http://www.boost.org/doc/libs/1_35_0/libs/circular_buffer/doc… contains the following line: // Create a circular buffer with a capacity for 3 integers. boost::circular_buffer<int> cb(3); But looking at the header file base.hpp in the circular_buffer directory, we have the following: template <class T, class Alloc> class circular_buffer { ...... }; The Alloc template parameter is not a default one, so I can't understand how we can instantiate cb in the example? Apologies if this is not strictly boost-user related. Regards, Jim

2 2

multi_array, resize and default constructable
by gast128 21 Aug '08

21 Aug '08

Dear all, from the documentation I read that if a multi_array is reshaped new elements are default constructed: "Resizing an Array The boost::multi_array class provides an element-preserving resize operation. ...Any new elements in the array are default constructed..." It is thus not possible providing a default fill element?

2 2

weak_ptr for intrusive_ptr
by Alan M. Carroll 21 Aug '08

21 Aug '08

I greatly prefer intrusive_ptr to shared_ptr, but one drawback of that is there is no equivalent of weak_ptr. I have started work on a class to do that and my biggest question, honestly, was what to name it. The basic logic turned out to be fairly simple. The target class declares a member that is an instance of the weak pointer. Other classes that want a weak pointer to the target instance also declare a member weak pointer, which must be initialized with a copy of the target instance member. The member provides a method to generate an intrusive_ptr to the target, which is either valid or nil depending on whether the target has been destructed. When the target and all weak pointers are destructed, everything gets cleaned up. The weak pointers don't affect the target reference count. No changes to Boost.intrusive_ptr are required. The one improvement I see would be to merge it into the reference counter utility class discussed earlier (optionally, of course - perhaps via a subclass of the reference counter). Yeah, I think I'll do that. My questions: 1) What would be a good name for such a class? I am using "tell_tale" for now, in analogy to tell tale lights on devices that go out when the device fails. Obviously "weak_ptr" is out. "weak_intrusive_ptr" seems a bit verbose, but may that's OK. 2) Is there any interest in Boostifying the class, or am I the only one who would use it? It's a matter of how much I indulge my idiosyncrasies.

4 8

Re: [Boost-users] Multi-index container (Modifying non-unique key in the container)
by JOAQUIN M. LOPEZ MUÑOZ 20 Aug '08

20 Aug '08

________________________________ De: boost-users-bounces(a)lists.boost.org [boost-users-bounces(a)lists.boost.org] En nombre de Ramesh [rramesh1(a)gmail.com] Enviado el: martes, 19 de agosto de 2008 20:16 Para: boost-users(a)lists.boost.org Asunto: Re: [Boost-users] Multi-index container (Modifying non-unique key in the container) On Wed, Aug 13, 2008 at 10:20 AM, JOAQUIN M. LOPEZ MUÑOZ <joaquin(a)tid.es<mailto:joaquin@tid.es>> wrote: ________________________________ De: boost-users-bounces(a)lists.boost.org<mailto:boost-users-bounces@lists.boost.org> [boost-users-bounces(a)lists.boost.org<mailto:boost-users-bounces@lists.boost.org>] En nombre de Ramesh [rramesh1(a)gmail.com<mailto:rramesh1@gmail.com>] Enviado el: martes, 12 de agosto de 2008 20:40 [...] Hmm... I'm not referring to your myclass wrapper, but rather to the fact that you're storing DataMaps objects into the container rather than A*s directly. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo > Sorry if I got your question wrong, I am storing only pointers to objects > inside the map and each instance of myclass would hold one such > container to hold pointers to objects of class A along with keys. Yes, but DataMap seems to *replicate* the keys that are already present in A. Cannot you just have the following? typedef multi_index_container< A*, indexed_by< ordered_unique< tag <Key1>, BOOST_MULTI_INDEX_MEMBER(A,std::string,Key1)>, ordered_non_unique< tag<Key2>,BOOST_MULTI_INDEX_MEMBER(A,long,Key2)>, ordered_unique< tag<Key3>,BOOST_MULTI_INDEX_MEMBER(A,long,Key3)> > > tDMap; Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

2 1

[Exception] 1.36.0: mutable Patch
by Peter Klotz 20 Aug '08

20 Aug '08

gcc 3.2 complains heavily about keyword mutable not being at the beginning of declarations. The attached patch fixes that. The C++ standard does not enforce mutable placement however since Boost is already full of compiler specific workarounds I would be happy if this patch could be applied. Regards, Peter. Peter Klotz Software Engineer Phone: +43 (0) 50 8648-4100 Fax: +43 (0) 50 8648-4111 E-Mail: peter.klotz(a)ith-icoserve.com ---------------------------------------------------------------- ITH icoserve technology for healthcare GmbH A-6020 Innsbruck, Innrain 98 www.ith-icoserve.com Rechtsform: Gesellschaft mit beschränkter Haftung Firmensitz: 6020 Innsbruck, Innrain 98 Firmenbuchnummer: FN 174117f Firmenbuchgericht: Innsbruck DVR: 0983039

2 3

[boost signal] problem with borland c++ builder 6
by Eric B 20 Aug '08

20 Aug '08

Hi I'm trying to use boost::signal to replace a library of my own It compiles well but at runtime It raises an exception on the following line boost::signal<> sig; the exception is raised in function_template.hpp template< typename FunctionObj, typename R BOOST_FUNCTION_COMMA BOOST_FUNCTION_TEMPLATE_PARMS > struct BOOST_FUNCTION_FUNCTION_OBJ_INVOKER { static R invoke(function_buffer& function_obj_ptr BOOST_FUNCTION_COMMA BOOST_FUNCTION_PARMS) { FunctionObj* f; if (function_allows_small_object_optimization<FunctionObj>::value) f = reinterpret_cast<FunctionObj*>(&function_obj_ptr.data); else f = reinterpret_cast<FunctionObj*>(function_obj_ptr.obj_ptr); return (*f)(BOOST_FUNCTION_ARGS); <<<<< exception raised here } }; Does the sig have to be initialized in a specific way ???

1 1

[GIL] Smart images
by Jan Funke 20 Aug '08

20 Aug '08

Hi, recently I wondered, whether there is any possibility to create a kind of "smart image", like the smart pointer of boost. What I'd like to have is an image, that frees it's allocated memory automatically on vanishing of the last view accessing it. Do you guys have any idea how to achieve this? Regards, Jan

3 2

boost:.tuple to tr1::tuple migration: default template args unspecified
by Markus Werle 20 Aug '08

20 Aug '08

> [ignore this gmane cheater line] Hi! Looks like migration from boost::tuple to std::tr1:.tuple is a lot more pain than I thought. I have some compile time magic class that makes use of the default template args of boost::tuple: template < typename T0 = boost::tuples::null_type, typename T1 = boost::tuples::null_type, typename T2 = boost::tuples::null_type, typename T3 = boost::tuples::null_type, typename T4 = boost::tuples::null_type, typename T5 = boost::tuples::null_type, typename T6 = boost::tuples::null_type, typename T7 = boost::tuples::null_type, typename T8 = boost::tuples::null_type, typename T9 = boost::tuples::null_type> struct string_to_tuple { // ... }; Now from the docs I see: namespace std { namespace tr1 { // [6.1.3] Class template tuple template <class T1 = unspecified , class T2 = unspecified , ..., class TM = unspecified > class tuple; which leaves me lost without typeof(std::tr1::ignore) at hand. Any idea how to get around this? Btw.: Why does the standard leave this type unspecified? To be more specific: rewrite this code based on std::tr1::tuple ;-) --- snip --- // Usage: // int main() // { // try // { // { // typedef boost::tuple<int, int> tuple_t; // // std::list<tuple_t> test = // string_to_tuple<int, int>::apply(" ( 1, 2 ) ( 3, 4)(5,6)"); // // std::copy(test.begin(), test.end(), // std::ostream_iterator<tuple_t> (std::cout, "\n")); // } // // { // typedef boost::tuple<unsigned int, int, double> tuple_t; // // std::list<tuple_t> test = // string_to_tuple<unsigned int, int, double>::apply // (" ( 1, -2 , 5.123) ( 3, 4,7.9)(5,6,8.6789)"); // // std::copy(test.begin(), test.end(), // std::ostream_iterator<tuple_t> (std::cout, "\n")); // } // // } // catch (std::exception const & e) // { // std::cerr << e.what() << std::endl; // } // } #ifndef BOOSTTUPLESFROMSTRING_H #define BOOSTTUPLESFROMSTRING_H // #define BOOST_SPIRIT_DEBUG_OUT std::cerr // #define BOOST_SPIRIT_DEBUG #include "Enforce.h" #ifndef PHOENIX_LIMIT #define PHOENIX_LIMIT 11 #else #if (PHOENIX_LIMIT < 11) #define ERROR_MESSAGE LOCATION ": " \ "PHOENIX_LIMIT must be a at least 11, but is " \ STRINGIZE(PHOENIX_LIMIT) #pragma message (ERROR_MESSAGE) #error Check the output for details #endif #endif #include <boost/config.hpp> // for BOOST_STATIC_CONSTANT #include <boost/spirit/core.hpp> #include <boost/spirit/attribute.hpp> #include <boost/spirit/core/non_terminal/rule.hpp> #include <boost/spirit/utility/lists.hpp> #include <boost/spirit/utility/loops.hpp> #include <boost/spirit/utility/confix.hpp> #include <boost/spirit/actor/push_back_actor.hpp> #include <boost/spirit/actor/assign_actor.hpp> #include <boost/spirit/phoenix/primitives.hpp> #include <boost/spirit/phoenix/functions.hpp> #include <boost/tuple/tuple.hpp> #include <boost/tuple/tuple_io.hpp> #include <list> #include <iterator> #include <algorithm> #include <string> namespace boost { namespace spirit { struct no_action { template< typename T, typename ValueT > void act(T& ref_, ValueT const& value_) const { // do nothing } template< typename T, typename IteratorT > void act( T& ref_, IteratorT const& first_, IteratorT const& last_ ) const { // do nothing } }; static inline boost::spirit::ref_value_actor<boost::tuples::null_type, no_action> assign_a(boost::tuples::null_type & nt) { boost::spirit::ref_value_actor<boost::tuples::null_type, no_action> na (nt); return na; } } // namespace boost } // namespace spirit namespace { struct append_tuple_to_container_impl { template <typename Container, typename String> struct result { typedef void type; }; template <typename Container, typename String> void operator()(Container& c, String const & s) const { typedef typename Container::value_type tuple_t; tuple_t t; std::istringstream ss(s); ss >> boost::tuples::set_open('(') >> boost::tuples::set_close(')') >> boost::tuples::set_delimiter(',') >> t; c.push_back(t); } }; phoenix::function<append_tuple_to_container_impl> const append_tuple_to_container = append_tuple_to_container_impl(); struct insert_as_tuple_impl { template <typename Container, typename T0, typename T1, typename T2, typename T3, typename T4, typename T5, typename T6, typename T7, typename T8, typename T9> struct result { typedef void type; }; template <typename Container, typename T0, typename T1, typename T2, typename T3, typename T4, typename T5, typename T6, typename T7, typename T8, typename T9> void operator()(Container & c, T0 const & t0, T1 const & t1, T2 const & t2, T3 const & t3, T4 const & t4, T5 const & t5, T6 const & t6, T7 const & t7, T8 const & t8, T9 const & t9) { c.push_back(boost::make_tuple(t0, t1, t2, t3, t4, t5, t6, t7, t8, t9)); } }; phoenix::function<insert_as_tuple_impl> const insert_as_tuple = insert_as_tuple_impl(); template < typename T0 = boost::tuples::null_type, typename T1 = boost::tuples::null_type, typename T2 = boost::tuples::null_type, typename T3 = boost::tuples::null_type, typename T4 = boost::tuples::null_type, typename T5 = boost::tuples::null_type, typename T6 = boost::tuples::null_type, typename T7 = boost::tuples::null_type, typename T8 = boost::tuples::null_type, typename T9 = boost::tuples::null_type> struct string_to_tuple { //////////////////////////////////////////////////////////////////////// //// // type to boost::spirit parser mapping template <typename T, int Dummy = 0> struct parser; template <int Dummy> struct parser<boost::tuples::null_type, Dummy> { static inline boost::spirit::epsilon_parser p() { boost::spirit::epsilon_parser result; return result; }; static inline boost::spirit::epsilon_parser comma() { boost::spirit::epsilon_parser result; return result; } }; #define PARSER_TRAITS(TYPE, PARSER_T) \ template <int Dummy> struct parser<TYPE, Dummy> \ { \ static inline \ PARSER_T p() \ { \ PARSER_T result; \ return result; \ } \ \ static inline \ boost::spirit::strlit<char const *> comma() \ { \ boost::spirit::strlit<char const *> str_p(","); \ return str_p; \ } \ } PARSER_TRAITS(int, boost::spirit::int_parser<int>); PARSER_TRAITS(unsigned int, boost::spirit::uint_parser<unsigned>); typedef boost::spirit::real_parser <double, boost::spirit::ureal_parser_policies<double> > real_parser_t; PARSER_TRAITS(float, real_parser_t); PARSER_TRAITS(double, real_parser_t); template <int Dummy> struct parser<std::string, Dummy> { typedef boost::spirit::contiguous <boost::spirit::confix_parser <boost::spirit::strlit<const char*>, boost::spirit::kleene_star <boost::spirit::anychar_parser>, boost::spirit::strlit<const char*>, boost::spirit::unary_parser_category, boost::spirit::non_nested, boost::spirit::non_lexeme> > parser_t; static inline parser_t p() { using namespace boost::spirit; using namespace phoenix; parser_t result = lexeme_d[confix_p("\"" , (*anychar_p) , "\"")]; return result; } static inline boost::spirit::strlit<char const *> comma() { boost::spirit::strlit<char const *> str_p(","); return str_p; } }; // PARSER_TRAITS(std::string, quoted_string_grammar); //////////////////////////////////////////////////////////////////////// //// // typedefs and integral constants typedef typename boost::tuple<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9> tuple_t; BOOST_STATIC_CONSTANT(int, tuple_len = boost::tuples::length<tuple_t>::value); //////////////////////////////////////////////////////////////////////// //// // static inline std::list<tuple_t> apply(std::string const & s) { using namespace boost::spirit; using namespace phoenix; std::list<tuple_t> result; T0 t0; T1 t1; T2 t2; T3 t3; T4 t4; T5 t5; T6 t6; T7 t7; T8 t8; T9 t9; typedef rule<phrase_scanner_t> rule_t; rule_t rule_tuple_rep = (str_p("(") >> parser<T0>::p()[assign_a(t0)] >> parser<T1>::comma() >> parser<T1>::p()[assign_a(t1)] >> parser<T2>::comma() >> parser<T2>::p()[assign_a(t2)] >> parser<T3>::comma() >> parser<T3>::p()[assign_a(t3)] >> parser<T4>::comma() >> parser<T4>::p()[assign_a(t4)] >> parser<T5>::comma() >> parser<T5>::p()[assign_a(t5)] >> parser<T6>::comma() >> parser<T6>::p()[assign_a(t6)] >> parser<T7>::comma() >> parser<T7>::p()[assign_a(t7)] >> parser<T8>::comma() >> parser<T8>::p()[assign_a(t8)] >> parser<T9>::comma() >> parser<T9>::p()[assign_a(t9)] >> ")")[insert_as_tuple(var(result), var (t0), var(t1), var(t2), var (t3), var(t4), var(t5), var (t6), var(t7), var(t8), var (t9))] ; rule_t rule_tuple_list = *(rule_tuple_rep) >> end_p // for trailing whitespace ; BOOST_SPIRIT_DEBUG_RULE(rule_tuple_rep); BOOST_SPIRIT_DEBUG_RULE(rule_tuple_list); parse_info<> info; try { info = parse(s.c_str(), rule_tuple_list, space_p); } catch (std::exception const & e) { std::cerr << e.what() << std::endl; } ENFORCE(info.full) ("Failed to generate a list of tuples from ") ("string representation\n'") (s)("'\n"); return result; } }; } // namespace #endif // BOOSTTUPLESFROMSTRING_H

2 2

[tr1] tuple / autoconversion problem
by Markus Werle 20 Aug '08

20 Aug '08

> [ignore this line: it makes gmane stop complaining about top-posting] Hi! Trying to migrate existing code from boost::xxx to std::tr1::xxx using the boost::tr1 implementation for Visual Studio 2005 SP1 In the presence of some exotic autoconversion utility the the std::tr1::tuple version of my code fails on vc8. The error messages indicate that the conversion operator is not considered by the compiler. Below is code that fails to compile on vc8 if USE_TR1 is defined Do you have an idea how to fix this? Thanx, Markus ---snip--- #include <boost/tr1/memory.hpp> #ifdef USE_TR1 #include <boost/tr1/tuple.hpp> #else #include <boost/tuple/tuple.hpp> #endif #include <boost/any.hpp> #include <iostream> namespace Core { class AutoConverter { std::tr1::shared_ptr<boost::any> t_; public: AutoConverter(std::tr1::shared_ptr<boost::any> const & t) : t_(t) {} template <typename C> operator C () { try { boost::any & a = (*t_); return boost::any_cast<C>(a); } catch(boost::bad_any_cast & e) { std::cerr << "Internal conversion bug: " << "Failed to convert data holder to " << typeid(C).name() << "\n" << e.what() << std::endl; C c = C(); return c; } } }; inline AutoConverter Demo() { #ifdef USE_TR1 std::tr1::shared_ptr<boost::any> p_result (new boost::any(std::tr1::make_tuple(1, 2, 3, 4))); #else std::tr1::shared_ptr<boost::any> p_result (new boost::any(boost::make_tuple(1, 2, 3, 4))); #endif return p_result; } } // namespace Core int main(int argc, char* argv[]) { #ifdef USE_TR1 std::tr1::tuple<int, int, int, int> test = Core::Demo(); #else boost::tuple<int, int, int, int> test = Core::Demo(); #endif return 0; } ---snip--- Error message is: >------ Build started: Project: TR1TupleConversionProblem, Configuration: Debug Win32 ------ 1>Compiling... 1>stdafx.cpp 1>TR1TupleConversionProblem.cpp 1>[...]\boost_1_36_0\boost\fusion\sequence\intrinsic\begin.hpp(56) : error C2504: 'boost::fusion::extension::begin_impl<Tag>::apply<Sequence>' : base class undefined 1> with 1> [ 1> Tag=boost::fusion::non_fusion_tag 1> ] 1> and 1> [ 1> Sequence=const Core::AutoConverter 1> ] 1> [...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp (65) : see reference to class template instantiation 'boost::fusion::result_of::begin<Sequence>' being compiled 1> with 1> [ 1> Sequence=const Core::AutoConverter 1> ] 1> [...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp (105) : see reference to function template instantiation 'boost::fusion::vector_data4<Derived,T0,T1,T2,T3> boost::fusion::vector_data4<Derived,T0,T1,T2,T3>:: init_from_sequence<Sequence>(const Sequence &)' being compiled 1> with 1> [ 1> Derived=boost::fusion::vector4<int,int,int,int>, 1> T0=int, 1> T1=int, 1> T2=int, 1> T3=int, 1> Sequence=Core::AutoConverter 1> ] 1> [...]\boost_1_36_0\boost\fusion\container\vector\vector.hpp(58) : see reference to function template instantiation 'boost::fusion::vector4<T0,T1,T2,T3>::vector4<T>(const Sequence &)' being compiled 1> with 1> [ 1> T0=int, 1> T1=int, 1> T2=int, 1> T3=int, 1> T=Core::AutoConverter, 1> Sequence=Core::AutoConverter 1> ] 1> [...]\boost_1_36_0\boost\fusion\tuple\tuple.hpp(33) : see reference to function template instantiation 'boost::fusion::vector<T0,T1,T2,T3,T4,T5,T6,T7,T8,T9>:: vector<Sequence>(const Sequence &)' being compiled 1> with 1> [ 1> T0=int, 1> T1=int, 1> T2=int, 1> T3=int, 1> T4=boost::fusion::void_, 1> T5=boost::fusion::void_, 1> T6=boost::fusion::void_, 1> T7=boost::fusion::void_, 1> T8=boost::fusion::void_, 1> T9=boost::fusion::void_, 1> Sequence=Core::AutoConverter 1> ] 1> [MYPATH]\tr1tupleconversionproblem.cpp(69) : see reference to function template instantiation 'boost::fusion::tuple<T0,T1,T2,T3,T4,T5,T6,T7,T8,T9>:: tuple<Core::AutoConverter>(const Sequence &)' being compiled 1> with 1> [ 1> T0=int, 1> T1=int, 1> T2=int, 1> T3=int, 1> T4=boost::fusion::void_, 1> T5=boost::fusion::void_, 1> T6=boost::fusion::void_, 1> T7=boost::fusion::void_, 1> T8=boost::fusion::void_, 1> T9=boost::fusion::void_, 1> Sequence=Core::AutoConverter 1> ] 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(65) : error C2039: 'type' : is not a member of 'boost::fusion::result_of::begin<Sequence>' 1> with 1> [ 1> Sequence=const Core::AutoConverter 1> ] 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(65) : error C2146: syntax error : missing ';' before identifier 'I0' 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(65) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(65) : error C2065: 'I0' : undeclared identifier 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(66) : error C2146: syntax error : missing ';' before identifier 'i0' 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(66) : error C2065: 'i0' : undeclared identifier 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(66) : error C2893: Failed to specialize function template 'const result_of::begin<const Sequence>::type boost::fusion::begin(const Sequence &)' 1> With the following template arguments: 1> 'Core::AutoConverter' 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(66) : error C2893: Failed to specialize function template 'const result_of::begin<Sequence>::type boost::fusion::begin(Sequence &)' 1> With the following template arguments: 1> 'const Core::AutoConverter' 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(67) : error C2955: 'boost::fusion::result_of::next' : use of class template requires template argument list 1> [...]\boost_1_36_0\boost\fusion\iterator\next.hpp(50) : see declaration of 'boost::fusion::result_of::next' 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(67) : error C2039: 'type' : is not a member of 'boost::fusion::result_of::next' 1> [...]\boost_1_36_0\boost\fusion\iterator\next.hpp(50) : see declaration of 'boost::fusion::result_of::next' 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(67) : error C2039: 'type' : is not a member of 'boost::fusion::result_of::next<Iterator>' 1> with 1> [ 1> Iterator=I1 1> ] 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(67) : error C2893: Failed to specialize function template 'const result_of::next<Iterator>::type boost::fusion::next(const Iterator &)' 1> With the following template arguments: 1> 'I1' 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(67) : error C2039: 'type' : is not a member of 'boost::fusion::result_of::next<Iterator>' 1> with 1> [ 1> Iterator=I1 1> ] 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(67) : error C2893: Failed to specialize function template 'const result_of::next<Iterator>::type boost::fusion::next(const Iterator &)' 1> With the following template arguments: 1> 'I2' 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(68) : error C2100: illegal indirection 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(68) : error C2100: illegal indirection 1>[...]\boost_1_36_0\boost\fusion\container\vector\detail\vector_n.hpp(68) : error C2100: illegal indirection

3 13

[Boost.Test] Looking for Workaround: Subprocesses exiting with 0 reported as fatal error
by Florian Winter 20 Aug '08

20 Aug '08

Hi, Using Boost.Test version 1.35.0, we have run into the following bug http://svn.boost.org/trac/boost/ticket/1723 Is there an easy way to work around or fix this problem in Boost 1.35.0 (such as a patch), so we are not forced to upgrade to the SVN version of Boost.Test? Unfortunately, not starting a sub process is not an option, because it is not our software that starts the sub process but some additional library that we use. In case we have to upgrade to the SVN version of Boost, is there a recent SVN revision or tag that you would consider stable and recommend for use? Thanks in advance for any help. best regards, Florian

5 8

Building Boost Program Options
by Alex Adranghi 20 Aug '08

20 Aug '08

Hi, I've recently decided to build the latest boost version myself, but I'm wondering why there are only shared objects for program options. Ideally I want to build static libraries. Thanks Alex

2 2

Re: [Boost-users] HOWTO: Building Boost for Windows 64-bit
by Gevorg Voskanyan 20 Aug '08

20 Aug '08

[snip] > According to http://tinyurl.com/6zeyhu, cflags affects both the C and C++ > compilers, while cxxflags affects only the C++ compiler; I use cxxflags as a > matter of habit, but in the case of -arch, I suppose cflags would be more > appropriate (although I'm not aware of any C code inside of Boost anyway). Interesting, this caught me by surprise since I thought that cflags was only for C, cxxflags for C++ and compileflags for both. It is documented that way at http://tinyurl.com/63rjal at least. A small testing revealed that http://tinyurl.com/6zeyhu appears to be correct under my environment. cflags affected both C and C++ and compileflags was rejected as an unknown feature. The environment was as follows: Boost.Build V2 (Milestone 12) Boost.Jam 03.1.16 gcc 4.2.2 What would be the correct description of these features? I appreciate all your input. Thanks, Gevorg

1 0

[filesystem] Changes to filesystem_error
by Arno 20 Aug '08

20 Aug '08

Hi all, I moved now from 1.31 to 1.35 and have some problem to understand what I have to change in the area of filesystem_error. I applied all the changes belongs to the iterator stuff and the class itself, but in my special error handling I use the 'who', 'error' and 'native_error' methods which I can not find in the actual model. Can you give me a clue, how I can get this information in 1.35. regards Arno

2 2

[filesystem] temp filenames?
by Hajo Kirchhoff 20 Aug '08

20 Aug '08

Hi all, I found an old (year 2003) feature request for filesystem: create temporary files, but do not see any methods in the current (1.36) version. Can anyone tell me what is the status on this? Best regards Hajo

1 0

boost.asio async_write/read_until guarantee
by Daniel Mierswa 20 Aug '08

20 Aug '08

Hi, if i have a threadpool running an io_service and a read_until is invoked before async_write. Now i wonder what would happen if the string is written to the socket, will the write handler be called before the read_handler or is it undefined in which order they will be invoked? If it's not guaranteed can anyone think of a solution to create such a guarantee in my own program? (I posted the same question on the asio mailinglist but i assume there's more activity here) Thanks in advance -- Mierswa, Daniel If you still don't like it, that's ok: that's why I'm boss. I simply know better than you do. --- Linus Torvalds, comp.os.linux.advocacy, 1996/07/22

2 1

1.35/1.36 thread library and date_time dependency
by Ross Wightman 20 Aug '08

20 Aug '08

After looking through the new 1.35/1.36 threading library (with a lot of nice changes), I am wondering why the decision to tie it to boost::date_time was made? I love date_time as a library, but I believe it's is too large and cumbersome to be tied to a core threading library. It pulls in an excessively large include tree whenever I want to use a mutex or conditional variable. The call tree for doing simple comparisons and calculations at second to nanosecond scales is also excessive. There will always be unnecessary converting from seconds and nanoseconds, into the date_time's internal date + ticks format, and back to seconds and nanoseconds. A more fully realized 'xtime' with functions for easy conversion to/from date_time in an optional header would be a much better approach in my opinion. The C++0x draft standard looks like it uses a lean 'system_time' class which is a small subset of date_time. Regards, Ross

1 0

Bug in 1.35/1.36 thread absolute timed waits
by Ross Wightman 20 Aug '08

20 Aug '08

There is an integer arithmetic bug in get_due_time() used by conditional variables in the boost 1.35/1.36 threading library. On line 343 in thread/src/win32/thread.cpp, integer division is performed before multiplication leaving the possibility of an erroneous 0 result in the case where ticks_per_second is larger than hundred_nanoseconds_in_one_second. Moving the brackets around the multiply or removing them altogether will fix this problem. I think this may only show itself if boost::date_time is setup so that BOOST_DATE_TIME_HAS_NANOSECONDS is true (the way I need it).

1 0

total newbie with quickbook
by e r 20 Aug '08

20 Aug '08

Hi, posted in gclb.doc but no luck so far, so i figured i'd try here: --- Things I did a) sudo apt-get install xsltproc docbook-xsl docbook-xml b) updated user-config.jam file as required c) installed SciTE --- Things I'm unsure about: 1) don't understand this part in the section about SciTE: You can use the following settings (qbk = *.qbk etc) to highlight quickbook tags when editing quickbook files. where should these settings be set? SciTE?! 2) Suppose i have a .qbk file. Where do I go from here? how do i build the html file with it? probably very basic, but... Thanks!

2 2

Re: [Boost-users] The problem isn't C's integer philosophy; it's your design. (was: size_type doubts / integer library..)
by Zeljko Vrba 19 Aug '08

19 Aug '08

On Mon, Aug 18, 2008 at 07:05:10PM -0400, Daryle Walker wrote: > > implementing. This is one of those times. > Thanks for your deep analysis and your time. Unfortunately, it's based on the assumption that the task ID is opaque, which it is not.. Re-reading my original post, this could be blamed on me.. > > >Integer types in C and C++ are a mess. For example, I have made a > >library > >where a task is identified by a unique unsigned integer. The extra > >information > >about the tasks is stored in a std::vector. When a new task is > [snip, rearrange] > > You tasks IDs are conceptually opaque, why is any external code > wanting to mess with them? The external code shouldn't be doing > There are TWO task IDs: one is used by the library (which I also made), and that one _is_ opaque (at least to library clients), it _is_ typedef, and it is not even an integer (it's a pointer). Now, to every created task, I need to assign a positive[*] index (in an application which just uses the library) which is _not_ opaque: the indices are vertex IDs which are in turn used to construct a CSR representation (edge-lists) of a certain graph which is in turn operated on by an external library. (You may remember my earlier post where I proposed that the CSR class from Boost.Graph provides a documented, public way of accessing the raw CSR vectors.) I will call these "other" IDs "task indices" to avoid further confusion. I could bundle the task index in the task structure and provide a function that takes the task ID and returns the index. This is not satisfactory for several reasons: - the task library should be general-purpose and lightweight (task indices might not be needed in certain applications) - task indices may be assigned to different policies, which I do not want to hard-code into the library - I do not want to complicate interfaces with optional information (e.g. extra index parameter to task creation -- see 1st point) Since the library is written in C (well defined ABI across compilers), I can't provide overloaded interfaces. Thus, I have chosen that the task library shall be minimalistic, and that extra information about tasks, where needed, shall be layered in external containers. In this particular application, the choice of the external container (vector) is dictated by a 3rd party library. > > (The ID is a typedef and not a naked "unsigned," right?) Anyway, > does it really matter; this ID generation code is only used during > task construction, right? > The "true" task ID (provided by the "task library") is a typedef and opaque, yes. The task index (used to construct a graph) is a plain int, not even a typedef. Why? [*] Because the external library uses plain ints[**] in its interfaces. The library can be configured to use longs, but then, fortunately, a compile-time error happens when passing &v[0] of vector<int> to long*. [**] Now, the library itself does not use plain int, but a typedef. But since *all* data is passed in terms of the same typedef (vertex/edge IDs, vertex/edge weights), this implies that I cannot configure the library to use unsigned integers and expect it to work correctly (because it does more complicated operations with weights than just indexing arrays). Which leads me to conclusion that the library interface is not ideal; it should define at least index_type and weight_type instead of the single number_type. But fixing the library is out of my scope - I have to work with what I have. > > Why are you using a number to refer to a container element in the > first place? Then I realized that you can't use iterators because > they're not stable with vector's element adds or removes. Then I > Correct. > > wondered, why are you using a vector in the second place? Wouldn't a > To interface with the external library, which has a C interface and requires a bunch of int* (actually, number_type, see above) arguments, to which I pass &v[0]. Vector is the only standard container which guarantees contiguous storage. And for the kind of data processing the library is doing, it is actually good choice. > > iterators, leaving them available to implement your ID type. And you > don't seem to need random-access to various task elements. (A deque > I do indeed not need random-access to "real tasks". In the task library I have actually implemented something similar the design you have proposed here. > > (I was going to suggest using Boost's pointer-containers, but then I > realized that you really don't need containment at all.) Now you'll > pass this class around instead of an integer type. The size may be > higher though, two pointers (and an 'int' in debug-mode). > Indeed -- I do not need containment and the task library just returns opaque task IDs -- it is the task creator's responsibility to keep track of them. Now, it is almost certainly true that in this project I do not need the full integer<T> class that I proposed, and even if it were available, it'd be too much to convert the project at this point. I like to rant, but I'm also pragmatic :-) boost.integer and numeric_cast will do (thanks to you and Dave for pointing it out) I'll leave the implementation of the proposed simpler, non-ranged integer<T> template as a challenge for myself and as a material for learning about other boost libraries :-) > > No, you should rethink your design on why you need integers in the > first place. > Compact storage of graphs that enables fast algorithms (e.g. cache-friendly layout, avoids frequent memory rellocations (unlike linked lists), etc.). And before you ask why I don't use Boost.graph: because I'm working with hypergraphs. A hypergraph can be represented as an ordinary bipartite graph, but such representation is too awkward. (Actually... time to think a bit about this premise :-))

3 2

Re: [Boost-users] Multi-index container (Modifying non-unique key in the container)
by JOAQUIN M. LOPEZ MUÑOZ 19 Aug '08

19 Aug '08

________________________________ De: boost-users-bounces(a)lists.boost.org [boost-users-bounces(a)lists.boost.org] En nombre de Ramesh [rramesh1(a)gmail.com] Enviado el: martes, 12 de agosto de 2008 20:40 Para: boost-users(a)lists.boost.org Asunto: Re: [Boost-users] Multi-index container (Modifying non-unique key in the container) > > > Thanks Joaquín, > > Will try modify & the reasons I am wrapping the map class with a another one is to make sure that > the users of the class just get access to APIs and not to the container as such & and also each key > is used by a different classes to do lookups. Hence two unique keys. Hmm... I'm not referring to your myclass wrapper, but rather to the fact that you're storing DataMaps objects into the container rather than A*s directly. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

2 1

HOWTO: Building Boost for Windows 64-bit
by cowwoc 19 Aug '08

19 Aug '08

Hi, I just ran across an excellent blog post showing how to build Boost for Windows 64-bit: http://einaros.blogspot.com/2007/06/compiling-boost-for-x64.html I had two questions: 1) Can the Boost team please add this to the official documentation? 2) Will the next public release include 64-bit binaries? Thank you, Gili -- View this message in context: http://www.nabble.com/HOWTO%3A-Building-Boost-for-Windows-64-bit-tp18973954… Sent from the Boost - Users mailing list archive at Nabble.com.

4 5

[Boost.Regex] regex_basic subpatterns iterators
by Mickael Wolff 19 Aug '08

19 Aug '08

Hi, I would like know if they are some method I missed to point parenthesis expression in basic_regex. For example, I would like to write something like this : === 8< === std::pair<std::string::iterator, std::string::iterator> mark ; boost::regex re("(\w+)") ; if(re.mark_count() == 2) { first_mark.first = re.marks[1].begin() ; first_mark.second = re.marks[1].end() ; } === 8< === My current solution is to do a regex on the regex, but I guess boost::regex did the work yet. Greetings, Mickaël. PS.: please apologize my english, I'm French. -- Mickaël Wolff aka Lupus Michaelis Racine <http://lupusmic.org> Blog <http://blog.lupusmic.org>

1 0

Boost.Regex 1.36.0 fails to compile with VS2005 compiler
by Peter Klotz 19 Aug '08

19 Aug '08

Boost.Regex 1.36.0 does not compile due to a compiler specific workaround in files libs\regex\src\usinstances.cpp and libs\regex\src\wc_regex_traits.cpp. The attached patch fixes the problem but will (likely) break linking for others. I use bjam 3.1.13 and obtain this error message: ...patience... ...found 1793 targets... ...updating 618 targets... compile-c-c++ bin.v2\libs\regex\build\msvc-8.0\release\threading-multi\wc_regex_traits.obj wc_regex_traits.cpp libs\regex\src\..\src\wc_regex_traits.cpp(53) : error C2375: 'std::allocator<_Ty>::allocator' : redefinition; different linkage with [ _Ty=unsigned short ] xmemory(120) : see declaration of 'std::allocator<_Ty>::allocator' with [ _Ty=unsigned short ] libs\regex\src\..\src\wc_regex_traits.cpp(53) : error C3190: 'std::allocator<_Ty>::allocator(void) throw()' with the pro vided template arguments is not the explicit instantiation of any member function of 'std::allocator<_Ty>' with [ _Ty=unsigned short ] cl /Zm800 -nologo @"bin.v2\libs\regex\build\msvc-8.0\release\threading-multi\wc_regex_traits.obj.rsp" ...failed compile-c-c++ bin.v2\libs\regex\build\msvc-8.0\release\threading-multi\wc_regex_traits.obj... ...failed updating 1 target... My bjam command line: bjam -q -sNO_COMPRESSION=1 --build-type=complete --without-graph --without-math --without-mpi --without-python --without-serialization --without-signals --without-wave --toolset=msvc-8.0 Regards, Peter. Peter Klotz Software Engineer Phone: +43 (0) 50 8648-4100 Fax: +43 (0) 50 8648-4111 E-Mail: peter.klotz(a)ith-icoserve.com ---------------------------------------------------------------- ITH icoserve technology for healthcare GmbH A-6020 Innsbruck, Innrain 98 www.ith-icoserve.com Rechtsform: Gesellschaft mit beschränkter Haftung Firmensitz: 6020 Innsbruck, Innrain 98 Firmenbuchnummer: FN 174117f Firmenbuchgericht: Innsbruck DVR: 0983039

4 9

compatibility between g++ and msvc8
by Guo Xu 19 Aug '08

19 Aug '08

#include <iostream> #include <vector> #include <boost/functional.hpp> #include <boost/algorithm/string.hpp> using namespace std; using namespace boost; int main() { vector<string> strs; strs.push_back( "Beijing" ); strs.push_back( "Olympic" ); strs.push_back( "Game" ); vector<string>::iterator it = std::find_if( strs.begin(), strs.end(), boost::bind2nd( boost::contains<string, string> , "mp" ) ); return 0; } why this part of programe can be compiled on the mscv8, but can not be compled on the g++? the error prompt is: stringalgo.cpp: In function 'int main()': stringalgo.cpp:29: error: no matching function for call to 'bind2nd(<unresolved overloaded function type>, std::string&)'

2 1

Extended Subgraph
by Alexander Löhr 19 Aug '08

19 Aug '08

Hi! Is there an extended version of subgraph.hpp available somewhere, which is able to remove subgraphs. I need something like: subgraph p(5) subgraph c = p.create_subgraph(); v1 = add_vertex(c); v2 = add_vertex(p); add_edge(v1, v2); p.remove_subgraph(c); In this case c should be removed from p and edge (v1,v2) and v1 should be destroyed. Thanks, Alex

1 0

Programming practices for asynchronous operations (asio, etc)
by dizzy 19 Aug '08

19 Aug '08

Hello I have recently started to rework a network server project that uses a thread per connection (with blocking/synchronous network I/O) handling model to using asio and an asynchronous operation model (where the number of threads should depend on hardware resources and be decoupled of software design constraints). The problem I have with this is that it makes one write too much boiler plate code for all those "completion handlers". Take very this simple example of code that is using the one thread per connection synchronous I/O model: // synchronously resolves, connects, throws on error connection con("1.2.3.4"); { // application "packet", usually known as "record" // uses "con" and starts an application packet with a given type packet pack(con, PacketTypeRequest); // serializes portably given data and synchronously sends the data // throws on error pack << uint32(10) << std::string("/home/user") << uint8(3); } // calls packet::~packet() which signals in the "con" stream end of packet Now to transform this very simple (I repeat, this is a very simple example, a lot more complex examples write "packets" of dozens of fields of which the last one may have "infinte" length meaning you cannot know the size of it to put it in the stream and you just have to send it as much as you can and then signal the end of the "packet") into an asynchronous version one would need: connection con; // breaks invariants of "con" being always connected // should asynchronously resolve and connect con.async_connect("1.2.3.4", handle_connect); // break code flow here // handle_connect() // breaks invariant of allowing "serialization" only after packet type // has been sent over the network packet pack(con); pack.async_serialize(uint32(10), handle_serialize1); // return to caller // handle_serialize1 pack.async_serialize(std::string("/home/user"), handle_serialize2); // return to caller // handle_serialize2 pack.async_serialize(uint8(3)), handle_serialize3); // return to caller // handle_serialize3 // breaks RAIIness of original packet which automatically signaled // "end" from the dtor of it pack.async_end, handle_endpacket); // return to caller And imagine that the original code was just a small function a big class, so now each such small function transforms into dozens of smaller functions, the code explosion is huge. I am curious to the code practices that some of you employ to solve these issues (to still have compile time checked code as much as possible by strong invariants and RAII idioms and not have to write millions of small functions). Some of the things I have thought of that seem to solve these issues: - instead of packets being adhoc serialized have structures encapsulating the network packets and have serialization code moved into them and let them deal with all the small functions (they could use some buffer to cache serialization of the fixed fields and async_write that buffer contents in a single operation); this however means an additional copy of the data vs how the code was before and it just moves the problem, instead of having many small functions in the high level code you have them in the lower level packet structures serialiation code (thu the output buffer being can reduce some of them) - using template expressions or whatever do some kind of "lazy evaluation"; basically still use syntax similar to the synchronous solution like: pack << uint32(10) << std::string("/home/user") << uint8(3); but this code instead of doing network I/O would enqueue the serialization actions needed have all those completion handlers internally and completely abstract to the user all those details; the user just does a pack.async_write(user_handler) and "user_handler" will be called after all the serializations have been asynchronously written - if this weren't C++ but C then we could use setjmp/longjmp to transparently (to the user) simulate synchronous operation while asynchronous operation is done behind the scenes; the user writes code such as: pack << uint32(10) << std::string("/home/user") << uint8(3); but what it does is on each op<< (each asynchronous serialization) the code does an async_write() with an internal handler, saves the context (setjmp) then longjmp()s to the previously saved context in the main event loop; when the async_write completes the handler does setjmp to restore the original user context and continue with the next op<< and so on; this however does not work in C++ because the jumped code path with longjmp may have exceptions being thrown/catched and as the standard says that's UB not to mention form what I could gather on the Internet some C++ compilers call dtors of auto objects when you longjmp "back" thus not leaving the original context untouched (which is what I need) -- Mihai RUSU "Linux is obsolete" -- AST

3 3

[Boost.Interprocess] int key and flat_multimap_index
by Robert Kubrick 19 Aug '08

19 Aug '08

A couple of beginner questions on basic_managed_heap_memory: 1) I want to access elements in the contiguous memory segment by using an int key, rather than a char string. Can I declare something like this: typedef basic_managed_heap_memory < int, /* my key is an integer */ rbtree_best_fit<null_mutex_family>, flat_map_index > managed_heap_memory; I need to lookup objects using an external integer ID but the ID can have any value (ie, does not match the 0-N array element order of my memory segment). 2) If I want to insert multiple objects with the same char* name (ala multimap) can I create a flat_multimap_index?

2 3

[[Boost]][[Interprocess]] Defining a common wrapper for all IPC-Types
by Daniel Clemens 19 Aug '08

19 Aug '08

Hi erveryone, The goal: I am currently on a coding project, that offers a common interface for all IPC-Types: - shared memory - message-queues - ... by meaning interface, I don't want the user to be bothered with the details of Inter process communication. I just want him to say what type he wants to use and then just use an instance of my class IPC and the read() or write() method, to simply use the according interprocess type provided by boost. this should be programmed for SLES 10 (=Suse Linux). I would like to have something like: class IPC{ //Attributes + string sName + int iStatus + iMaxMsgSize + iMaxMessages + enum ipcType //Methods + IPC();//constructor + string read(); + void write(string); }//end class The explanation of the code: Depending on the type I suggest on creation of an IPC-Instance the rest should be handled by the class - e.g. instanciating a boost::interprocess::message_queue mq( foo ); Now the question I have is, if the containers offer some sort of way of providing this functionality. Maybe I am currently just too blind to find the answer to the problem. Approaches so far (and failures): My current approach is, that depending on the type-setting, the read() and write() methods use the boost.Interprocess libraries to ither build a message_queue or a shared memory. The example provided for message_queues works fine. I then tried to assign an instance of boost::interprocess:message_queue to an attribute of an instance of IPC. But it says I am assigning a temporary to a pointer. I then tried assigning not an address, but to return a boost::interprocess:message_queue instance from the read()-method and assign it to an attribute. It seems it called the copy-constructor and didn't like that approach ither. Aproach suggestion and questions: Now I thought that the solution to getting a re-usable message_queue working is to use the pointers provided with the boost::interprocess to assign an instance of the established message-queue to the IPC-instance-Attribute. Is this the right way of doing this? And if so, could you give me an example? Thank you! -- GMX startet ShortView.de. Hier findest Du Leute mit Deinen Interessen! Jetzt dabei sein: http://www.shortview.de/wasistshortview.php?mc=sv_ext_mf@gmx

2 1

size_type doubts / integer library..
by Zeljko Vrba 19 Aug '08

19 Aug '08

Integer types in C and C++ are a mess. For example, I have made a library where a task is identified by a unique unsigned integer. The extra information about the tasks is stored in a std::vector. When a new task is created, I use the size() method to get the next id, I assign it to the task and then push_back the (pointer to) task structure into the vector. Now, the task structure has also an "unsigned int id" field. In 64-bit mode, sizeof(unsigned) == 4, sizeof(std::vector::size_type) == 8 I get a warnings about type truncation, and obviously, I don't like them. But I like explicit casts and turning off warnings even less. No, I don't want to tie together size_type and task id type (unsigned int). One reason is "aesthetic", another reason is that I don't want the task id type to be larger than necessary (heck, even a 16-bit type would have been enough), because the task IDs will be copied verbatim into another std::vector<unsigned> for further processing (edge lists of a graph). Doubling the size of an integer type shall have bad effects on CPU caches, and I don't want to do it. What to do? Encapsulate into "get_next_id()" function? Have a custom size() function/macro that just casts the result of vector::size and returns it? == Another example: an external library defines its interfaces with signed integer types, I work with unsigned types (why? to avoid even more warnings when comparing task IDs with vector::size() result, as in assert(task->id < tasks.size()), which are abundant in my code). Again, some warnings are unavoidable. What to do to have "clean" code? == Does anyone know about an integer class that lets the user define the number of bits used for storage, lower allowed bound and upper allowed bound for the range? Like: template<int BITS, long low, long high> class Integer; BITS would be allowed to assume a value only equal to the one of the existing integer types (e.g. 8 for char, 16 for short, etc.), and the class would be constrained to hold values in range [low, high] (inclusive). All operations (+-*/<<>><>) would be compile-time checked to make sense. For example, it would be valid to add Integer<32, 0, 8> with Integer<8, 0, 8> and store into Integer<8, 0, 16> (or Integer<8, 0, 17>) result, but NOT into Integer<8, 0, 8> result. The operations would also be checked at run-time to not overflow. Address-of operator would convert to signed or unsigned underlying integer type, depending on the lower bound. Mixing operations with native integer types would be allowed, provided ranges are respected[*]. And, of course, the library should have a "production mode" where the class would turn off all checks. Does anybody know about such a library? Is a unified numeric tower too much to ask for, at least in the form of a library? How do you deal with these issues? [*] If there's no such library in existence, I might be willing to think about a set of "sane" axioms and checks for automatic conversions. And I have "Hacker's Delight" at home, so I can peek into it and get formulas for deriving bounds of arithmetic operations. And yes, is this even easily implementable within C++ template framework; one has to deal with integer overflow.. What happens in template<long A, long B> class blah { const long T = A+B; }; when A+B overflows? Compiler error? Undefined result? Did C++0x do anything to clean up the integer types mess? This is a proposal for extension to the C language: http://www.cert.org/archive/pdf/07tn027.pdf Anything similar available for C++? </rant> Or should I just listen to the devil on my shoulder and turn off the appropriate warnings?

9 29

[Intrusive] compile error with codewarrior
by David Klein 19 Aug '08

19 Aug '08

hi all, i'm trying to use the intrusive library but can't compile anything. i also tried member_hook's and the slist instead of list but it fails with the same error. any ideas on how to fix this? #include <boost/intrusive/list.hpp> struct foo : public list_base_hook<> { }; void dummy( void ) { list<foo> l; } 1>..\..\include\boost\intrusive\list.hpp(1435): illegal non-type template argument 1>..\..\include\boost\intrusive\list.hpp(1435): (point of instantiation: 'dummy()') 1>..\..\include\boost\intrusive\list.hpp(1435): (instantiating: 'boost::intrusive::list<foo, boost::intrusive::none, boost::intrusive::none, boost::intrusive::none>') 1>..\..\include\boost\intrusive\list.hpp(1435): (instantiating: 'boost::intrusive::list_impl<boost::intrusive::listopt<boost::intrusive::detail::base_hook_traits<foo, boost::intrusive::list_node_traits<void *>, 1, boost::intrusive::default_tag, 1>, unsigned long, true>>') 1>..\..\include\boost\intrusive\list.hpp(1435): note: (corresponding point of instantiation for 'boost::intrusive::list_impl<boost::intrusive::listopt<boost::intrusive::detail::base_hook_traits<foo, boost::intrusive::list_node_traits<void *>, 1, boost::intrusive::default_tag, 1>, unsigned long, true>>') 1>..\src\main.cpp(15): note: (corresponding point of instantiation for 'boost::intrusive::list<foo, boost::intrusive::none, boost::intrusive::none, boost::intrusive::none>') compiler: metrowerks c/c++ for embedded arm version 3.0 build 138 (it's the compiler for the nintendo ds platform) boost version: 1.35 + 1.36 -- regards, dave

2 1

Boost.Filesystem 1.36.0: Define BOOST_FILESYSTEM_NO_DEPRECATED no longer works
by Peter Klotz 19 Aug '08

19 Aug '08

#include <boost/filesystem/convenience.hpp> int main(void) { return 0; } When compiling the above code with gcc 4.1 and define BOOST_FILESYSTEM_NO_DEPRECATED I obtain these error messages: boost/filesystem/convenience.hpp: In function 'std::string boost::filesystem::extension(const boost::filesystem::path&)': boost/filesystem/convenience.hpp:98: error: expected primary-expression before '>' token boost/filesystem/convenience.hpp: In function 'std::wstring boost::filesystem::extension(const boost::filesystem::wpath&)': boost/filesystem/convenience.hpp:100: error: expected primary-expression before '>' token boost/filesystem/convenience.hpp: In function 'std::string boost::filesystem::basename(const boost::filesystem::path&)': boost/filesystem/convenience.hpp:103: error: expected primary-expression before '>' token boost/filesystem/convenience.hpp: In function 'std::wstring boost::filesystem::basename(const boost::filesystem::wpath&)': boost/filesystem/convenience.hpp:105: error: expected primary-expression before '>' token boost/filesystem/convenience.hpp: In function 'boost::filesystem::path boost::filesystem::change_extension(const boost::filesystem::path&, const std::string&)': boost/filesystem/convenience.hpp:108: error: expected primary-expression before '>' token boost/filesystem/convenience.hpp:108: warning: left-hand operand of comma has no effect boost/filesystem/convenience.hpp: In function 'boost::filesystem::wpath boost::filesystem::change_extension(const boost::filesystem::wpath&, const std::wstring&)': boost/filesystem/convenience.hpp:110: error: expected primary-expression before '>' token boost/filesystem/convenience.hpp:110: warning: left-hand operand of comma has no effect boost/system/error_code.hpp: At global scope: It works, when compiled without BOOST_FILESYSTEM_NO_DEPRECATED. The problem seems to be a new #ifndef in convenience.hpp that did not exist in 1.35.0. Regards, Peter. Peter Klotz Software Engineer Phone: +43 (0) 50 8648-4100 Fax: +43 (0) 50 8648-4111 E-Mail: peter.klotz(a)ith-icoserve.com ---------------------------------------------------------------- ITH icoserve technology for healthcare GmbH A-6020 Innsbruck, Innrain 98 www.ith-icoserve.com Rechtsform: Gesellschaft mit beschränkter Haftung Firmensitz: 6020 Innsbruck, Innrain 98 Firmenbuchnummer: FN 174117f Firmenbuchgericht: Innsbruck DVR: 0983039

1 0

Re: [Boost-users] size_type doubts / integer library..
by Lang Stefan 19 Aug '08

19 Aug '08

-----Ursprüngliche Nachricht----- On Mon, Aug 18, 2008 at 12:06:08PM +0200, Lang Stefan wrote: > > > A) you intend to use your ID to later reference some address or offset > > (which is the same) in memory. If that is your intention, then you > > should stick to the size type (i. e. std:size_t). Problem solved. > > > Yes, it is used as an index into a vector. And that's what I did (typedef vector<..>::size_type pin_id). Well, then why don't you simply use std::size_t ? Yes, it's unsigned, and I agree with you it's not perfect (see below). But it will immediately rid you of all those nasty conversion warnings! > Hm, do they? Correct me if I'm wrong, but I don't think that C++ mandates flat address space -- it just > requires that each individual object has a contiguous memory representation. And there can be discrepancy > between the two, e.g. 80286 protected mode: largest segment size is 64k, yet the largest amount of > addressable memory is 16MB (or even in the range of TB if one allocates all LDTs and plays with swapping). Bugger, you're right, didn't think of that. > So, size_type should be able to represent the size of a *single* largest representable object. Why use it > for e.g. number of elements in a vector? That is something I did give some thought about in the past, to the point where I considered implementing my own set of container classes! However, I realized that in a sense, 'size_type' is indeed the correct type for an index. The reason behind it is this: an index type needs to be able to address a range of values that spans the minimum (0) and maximum (?) possible index for a container of some arbitrary type. For the STL, the smallest entity you can put inside a container is a single byte (disregarding bit-arrays). And the maximum number of such entities a container could legally contain would be limited by the amount of memory available divided by the size of the contained elements. While, as you pointed out, there doesn't need to be a direct relation from index to memory address, the range an index type needs to cover is equal to the range a 'size_type' needs to cover. Moreover, at least on a small scope, every architecture I am aware of groups values of container elements into one or more chunks of memory, which in turn store adjacent values into adjacent memory slots. So at least on a local scale, index values do correspond to memory addresses or memory offsets. > The "problem" could be solved by using largest _signed_ type both for size_type and difference_type. [snip] > So I'd advocate signed representation for size_type and difference_type. I agree. Stefan

4 6

program_options does not compile
by dejfson 19 Aug '08

19 Aug '08

Dear All, if I try this piece of code: ---------------------------------------------- --------------------------------------------- extern "C" { #include <vmeapi.h> } #include <iostream> #include <signal.h> #include <string> #include <boost/program_options.hpp> // FANCY THINGY HERE: IF YOU INCLUDE CURSES BEFORE STRING, IT WILL BREAK COMPILATION #include <curses.h> //using namespace std; //namespace po = boost::program_options; static void sig_catch(int sig) { VME_Release(); /* Exception handler */ switch(sig) { case SIGINT : case SIGTERM : // nl(); // echo(); cout << "\nVME safe exit." << endl; VME_Release(); if (VME_IsErr()) { cout << "Errors at VME_Release():" << endl; VME_DispErr(); } exit(0); break; default : break; } } int main (int argc, char **argv) { /* Init VME access */ VME_Init(); if (VME_IsErr()) { VME_DispErr(); cout << "^C to quit." << endl;; } /* Turn off auto error reporting */ VME_ErrQuiet(); /* Install signal handler */ if (signal(SIGINT, &sig_catch) == (void *) -1) cout << "VMET Can't install SIGINT handler." << endl; if (signal(SIGTERM, &sig_catch) == (void *) -1) cout << "VMET Can't install SIGTERM handler." << endl; cout << "works somehow" << endl; VME_Release(); if (VME_IsErr()) VME_DispErr(); } ---------------------------------------------------------- ---------------------------------------------------------- it does not compile. Compilator identifies the problem as: g++ -pipe -fcommon -I/acc/local/ppc4/include -D__NO_INCLUDE_WARN__ -I/user/biswop/include -I./include -c main.cpp -o main.ppc4.o In file included from /acc/local/ppc4/include/boost/program_options.hpp:15, from main.cpp:8: /acc/local/ppc4/include/boost/program_options/parsers.hpp:156: parse error before `>' make: *** [main.ppc4.o] Error 1 ------------------------------------------------------------ By looking on the code in parsers.hpp I do not see any particular breaks, thus I suspect that there is something very odd with compiler. This piece of code is used on PPC processors in VME industrial crates. The operating system is LynxOS, however it uses quite old version of compiler - 2.95.3. I do not have any chance how to upgrade it as we use this compiler everywhere. Boost version is 1.33.1 (and again no chance to upgrade, however in this respect I could very probably force cross-compiler to compile the library) I would appreciate any info/hint how to make it running by using this compiler. Thanks a lot d.

2 1

How to transform a single-threaded program into a multi-threaded program? (Source example)
by Stephen Torri 18 Aug '08

18 Aug '08

What I am trying to learn how to do is convert a single threaded program into a multi-threaded program. The task of the program is to analyze a text file a set number of times. Each analysis of the text file does not depend on another. The only thing that they need is the name of the file, how many iterations of the analysis to do and a unique id. I am not concerned about the information from each round being printed in sequential order. That is for example if thread A has a unique ID of 50 and thread B has a unique ID of 51 that I want thread B's output ahead of thread A's output. The output is going to be captured into a file and post-processed in a spreadsheet application. Below is a running example of what I am trying to do. To restate my question: How do I use boost threads to make a multi-threaded version of this program? Stephen ----- EXAMPLE CODE ----- #include <boost/bind.hpp> #include <boost/cstdint.hpp> #include <boost/format.hpp> #include <boost/program_options.hpp> #include <boost/shared_ptr.hpp> #include <boost/thread/thread.hpp> #include <iostream> #include <string> #include <sstream> class Work { public: std::string process ( boost::uint32_t round_number, boost::uint32_t iterations, std::string file ) { // Read file for data std::stringstream result; for ( boost::uint32_t index = 0; index != iterations; ++index ) { // Perform algorithm and save best result result << boost::format ("%1%:%2%") % round_number % index << std::endl; } return result.str(); } }; int main (int argc, char** argv) { boost::program_options::options_description generic ( "Generic options" ); generic.add_options() ( "help", "produce help message" ) ( "file", boost::program_options::value<std::string>(), "Target file" ) ( "rounds", boost::program_options::value<boost::uint32_t>(), "Number of rounds (default: 1)" ) ( "iterations", boost::program_options::value<boost::uint32_t>(), "Number of iterations (default: 5)" ); boost::program_options::variables_map vm; boost::program_options::store ( boost::program_options::command_line_parser ( argc, argv ). options(generic).run(), vm ); boost::program_options::notify ( vm ); if ( vm.count ( "help" ) ) { std::cout << generic << std::endl; return 0; } // Get values from command flags boost::uint32_t m_rounds = 1; boost::uint32_t m_iterations = 5; if ( vm.count ( "rounds" ) ) { m_rounds = vm["rounds"].as<boost::uint32_t>(); if ( m_rounds == 0 ) { std::cout << " Invalid number of rounds: 0" << std::endl; return 0; } } if ( vm.count ( "iterations" ) ) { m_iterations = vm["iterations"].as<boost::uint32_t>(); if ( m_iterations == 0 ) { std::cout << " Invalid number of iterations: 0" << std::endl; return 0; } } std::cout << "Number of rounds: " << m_rounds << std::endl; std::cout << "Number of iterations: " << m_iterations << std::endl; boost::shared_ptr<Work> data_alg_ptr ( new Work() ); for ( boost::uint32_t index = 0; index < m_rounds; ++index ) { std::cout << data_alg_ptr->process ( index, m_iterations, "data.txt" ) << std::endl; } return 0; }

2 1

Re: [Boost-users] [swap] How to override swap now?
by Joseph Gauterin 18 Aug '08

18 Aug '08

Hi Terry, >How should a user/developer like me implement a custom swap so that users >get the benefit of my::swap, then boost::swap, and finally std::swap without >putting too much burden on my user. In the same way that swap functions are currently provided: either a specilization of std::swap or a 'swap' function in the same namespace as a UDT. >If the user does this... >using namespace std; >using namespace boost; >using namespace my; >And then somewhere in his code... > HisType a = MakeA(); > HisType b = MakeB(); > swap(a, b); // Unqualified? Or should the user specify a namespace? > Which one? A call to std::swap will swap the two values using temporary values and assignments. A call to boost::swap will call my::swap using argument dependent lookup. A call to my::swap will just call my::swap. An unqualified call to swap will call my::swap using argument dependent lookup. >If the user has his own swap(HisType, HisType) invoke that. >Otherwise, if HisType.swap() exists, then use that. >Otherwise, use my::swap() if its "better" than boost::swap >Otherwise, use boost::swap(), if its "better" than std::swap >Otherwise, just use std::swap(). boost::swap calls my::swap() if it exists, else it calls std::swap(). HisType.swap is not considered directly. >Sorry about all the ambiguity. But that's the real problem, isn't it? Indeed - but we're using a trick to make sure that boost::swap is never ambiguous with std::swap. So: using namespace std; using namespace boost; swap(a, b); Will call a function called swap in the namespace where 'a' is declared if it exists (adl), or std::swap otherwise. It will never call boost::swap. std::swap(a, b); Will swap 'a' and 'b' using temporaries and assignments. boost::swap(a, b); Will call a function called swap in the namespace where 'a' is declared if it exists, or std::swap otherwise. No 'using' statements or declarations are required. Joe.

1 0

[Function] Comparing function objects with std::find
by Christian Larsen 18 Aug '08

18 Aug '08

Hi, I'm storing function objects in a std::vector, but to remove one again, I need to find an iterator to the one I want to remove. I do this in an "unregister" function taking a single boost::function<void ()> as parameter. Inside the function I would like to use the std::find algorithm to get an iterator to that function in the vector. I'm getting compile errors, though; see the example below. How do I fix these? I'm using MSVC++ 8 (SP1), and Boost 1.33.1 (can not upgrade). Example, where in my "unregister" function I use find as in the last part of this example (i.e. I have a Listener and not a plain function pointer). This does not compile: #include <algorithm> #include <vector> #include <boost/function.hpp> using namespace std; using namespace boost; void listenerA() {} void listenerB() {} int main() { typedef function<void ()> Listener; typedef vector<Listener> ListenerVector; ListenerVector listeners; listeners.push_back(&listenerA); listeners.push_back(&listenerB); ListenerVector::iterator iter; // This compiles and works iter = find( listeners.begin(), listeners.end(), &listenerB); assert(iter != listeners.end()); // This gives: // error C2666: 'boost::operator ==' : 4 overloads have // similar conversions iter = find( listeners.begin(), listeners.end(), Listener(&listenerB)); assert(iter != listeners.end()); return 0; } Compiler errors: c:\program files (x86)\microsoft visual studio 8\vc\include\algorithm(40) : error C2666: 'boost::operator ==' : 4 overloads have similar conversions d:\development\boost_1_33_1\boost\function\function_template.hpp(583): could be 'void boost::operator ==<R,Allocator>(const boost::function0<R,Allocator> &,const boost::function0<R,Allocator> &)' [found using argument-dependent lookup] with [ R=void, Allocator=std::allocator<void> ] d:\development\boost_1_33_1\boost\function\function_base.hpp(609): or 'bool boost::operator ==<boost::function<Signature>>(Functor,const boost::function_base &)' [found using argument-dependent lookup] with [ Signature=void (void), Functor=boost::function<void (void)> ] d:\development\boost_1_33_1\boost\function\function_base.hpp(600): or 'bool boost::operator ==<_Ty>(const boost::function_base &,Functor)' [found using argument-dependent lookup] with [ _Ty=boost::function<void (void)>, Functor=boost::function<void (void)> ] or 'built-in C++ operator==(void (__thiscall boost::function0<R,Allocator>::dummy::* )(void), void (__thiscall boost::function0<R,Allocator>::dummy::* )(void))' with [ R=void, Allocator=std::allocator<void> ] while trying to match the argument list '(boost::function<Signature>, const boost::function<Signature>)' with [ Signature=void (void) ] c:\program files (x86)\microsoft visual studio 8\vc\include\algorithm(74) : see reference to function template instantiation '_InIt std::_Find<std::_Vector_iterator<_Ty,_Alloc>,_Ty>(_InIt,_InIt,const _Ty &)' being compiled with [ _InIt=std::_Vector_iterator<Listener,std::allocator<Listener>>, _Ty=Listener, _Alloc=std::allocator<Listener> ] d:\development\misc\functionvector\functionvector.cpp(35) : see reference to function template instantiation '_InIt std::find<std::_Vector_iterator<_Ty,_Alloc>,boost::function<Signature>>(_InIt,_InIt,const _Ty &)' being compiled with [ _InIt=std::_Vector_iterator<Listener,std::allocator<Listener>>, _Ty=Listener, _Alloc=std::allocator<Listener>, Signature=void (void) ] Best regards, Christian

2 5

Boost.Time_series library
by Kim Tang 18 Aug '08

18 Aug '08

Hi all, i ve downloaded the time_series.zip by the link: http://boost-consulting.com/vault/index.php?directory=Math%20-%20Numerics and unzip it on my computer. But the compilation of the example (time_series\time_series\main.cpp) program fails due to the errors: c:\boost\time_series\boost\sequence\size.hpp(27) : error C2143: syntax error : missing ';' before '<' 1> c:\boost\time_series\boost\sequence\size.hpp(33) : see reference to class template instantiation 'boost::sequence::impl::size<S,T>' being compiled 1>c:\boost\time_series\boost\sequence\size.hpp(27) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int 1>c:\boost\time_series\boost\sequence\size.hpp(27) : error C2238: unexpected token(s) preceding ';' 1>c:\boost\time_series\boost\sequence\size.hpp(29) : error C2143: syntax error : missing ';' before '(' 1>c:\boost\time_series\boost\sequence\size.hpp(29) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int 1>c:\boost\time_series\boost\sequence\size.hpp(30) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int After looking at the file boost\time_series\boost\sequence\size.hpp i see that the variable name range_size in line 27 is unknown. So my question is which file should i include? I ve searched for the variable name range_size in the time_series folder. And one possibility is the file boost\detail\range_concepts.hpp. But is this the right file? Thanks, Kim Tang

4 3

shared_ptr custom deallocator - member function?
by Alejandro Martinez 18 Aug '08

18 Aug '08

can i use some class's (a kind of factory) member be used as a deallocator in a shared_ptr? like to do something like this: boost::shared_ptr<mysqlpp::Connection> cp(sDbPool->grab(), boost::bind(&mysqlpp::ConnectionPool::release, sDbPool)); where sDbPool is a shared_ptr to the "factory/pool manager". i tryed just that, but visual studio express 2008 keeps crashin on me. (the compiler crashes, not the program). any ideas?

2 2

bjam only finding system python on mac
by David Philp 18 Aug '08

18 Aug '08

I am trying to write a python extension for the Python that comes with Sage (Sage bundles its own Python). My user-config.jam is supposed to direct bjam to the Sage version of Python, but whatever I do, it links to the System Python. I think my configuration is correct, because if I (as root) move the System Python.framework so that bjam cannot find it, I can compile a working extension. ("Working" in the sense that it can be loaded into Sage's python, and runs perfectly.) Otherwise (without hiding System Python), the extension compiles just fine, but cannot be loaded into the Sage version of python. When loaded into Sage's python, it fails with "Fatal Python error: Interpreter not initialized (version mismatch?)" which seems reasonable. The extension can be loaded into the System Python. Here are the details. I've used "Sage_root" for the base directory of Sage to make this a bit more readable. (It is actually /Users/dphilp/ sage-3.0.3.): boost 1.35.0 sage 3.0.3, which contains python 2.5.2p2 (slightly patched for sage, and is built using --enable-framework=Sage_root/local/Frameworks/Python.framework ) Everything seems to work fine, Sage's doctests run perfectly, etc. In user-config.jam (this is overkill, but I wanted to remove any possible ambiguity): using python : 2.5 : Sage_root/local/Frameworks/Python.framework/Versions/2.5/bin/python : Sage_root/local/Frameworks/Python.framework/Versions/2.5/include/ python2.5 : Sage_root/local/Frameworks/Python.framework/Versions/2.5/lib/ python2.5/config ; bjam --debug-configuration reports that it is using the requested version of python, i.e. the one inside Sage. Using --with-python=... on the command line does not help. When I use --debug-building, there is no hint of the System Python.framework anywhere. But when I run otool -L my_ext.so, it reports that the extension is linked to the System framework---that is, unless I hide the System framework, in which case it reports that it is linked to the Sage framework. This seems to me to be a bug in bjam, but I would appreciate any help either way. (Moving the System's python doesn't seem to be a good long term solution!) Thanks in advance for any answers or redirections. David ================================== David J Philp Postdoctoral Fellow National Centre for Epidemiology and Population Health Building 62, cnr Mills Rd & Eggleston Rd The Australian National University Canberra ACT 0200 Australia T: +61 2 6125 8260 F: +61 2 6125 0740 M: 0423 535 397 W: http://nceph.anu.edu.au/ CRICOS Provider #00120C

2 2

STL iterator issue in signals::detail::named_slot_map_iterator on MS VisualStudio?
by Ákos Maróy 18 Aug '08

18 Aug '08

Hi, I'm trying to compile a code sample using boost signals on Windows using Visual Studio 2008, that works fine on Linux using gcc. My application crashes at the first time a signal's operator() method is called, and it seems that the issue is with some STL-related iterator magic. The application breaks in named_slot_map.hpp, in the call to boost::signals::detail::named_slot_map_iterator::init_next_group(), basically in operator== of class _Tree_nod, in file xtree - probably an MS STL implementation. basically it breaks here: #if _HAS_ITERATOR_DEBUGGING if (this->_Mycont == 0 || this->_Mycont != _Right._Mycont) { _DEBUG_ERROR("map/set iterators incompatible"); _SCL_SECURE_INVALID_ARGUMENT; } #else I tried to search on the issue, and found this thread: https://lists.secondlife.com/pipermail/sldev/2008-July/010867.html this even specifying _SECURE_SCL=0 doesn't help. I'm using boost 1.35.0, linking againts libboost_signals_vc90-mt-1_35. at the time of the call, actually there are no listeners bound to the signal. Is this an issue with boost::signals? or with MS VS? Akos

2 2

XML Serialization forward compatibility
by Terdale, Shantibhushan 18 Aug '08

18 Aug '08

I am trying to use XML serialization for streaming data on network. I could understand that with versioning you can make any class backward compatible. I have a situation which demands the other way; I need to read and construct an old object from new XML data. Currently it throws stream_error exception for any newly added member. I am trying to figure out how to deal with it; either write new archive or derive from existing XML archive and do changes etc. I am wondering whether anybody has done any work towards this idea and would like to share their insight. Thanks Shanti

2 1

Re: [Boost-users] size_type doubts / integer library..
by Lang Stefan 18 Aug '08

18 Aug '08

-----Ursprüngliche Nachricht----- > > If the developer > > chooses either type, others looking at the code might not recognize that > > certain values outside that range (but well within the limits of the > > chosen type) will cause problems or might indicate an error elsewhere. > > That's the job of the programmer. You have the native types with platform > dependent ranges. Good. That's a good start (without which you couldn't do > anything anyways). Now you need integer types to be defined in terms of > ranges, ok, you can do it with templates. Arbitrary precision arithmetic is > not the C++ standard IMO, it sits perfectly fine in third-party library space. > There was also a BigNum boost library proposal for GSoC. After that is done > then maybe everyone will be happy about this. > > -- > Dizzy > "Linux is obsolete" -- AST I am not sure you got my meaning. What I was trying to point out that today, like thirty years ago, when a programmer looks at a variable, he has to consider what integral type it fits in. And he needs to do so in terms of the machine! (can you say DWORD?) This implies two anachronisms: 1) the programmer needs to know the exact range the built-in integral types cover. While this is not a big problem, the mere fact a programmer needs to know such internal details indicates a design problem of the language. 2) the programmer can not easily express the true limits of the integral variables he uses: if he needs to make sure a variable does not exceed a certain limit, this requires excessive testing, or alternativly substituting his type with a custom class. On top of that he needs to devise mechanisms that prevent other programmers from circumventing these limitations. These two artifacts of the C language are the cause for uncountable runtime errors. If a programmer wasn't forced to think about internal representations and could instead just define the type he needs in terms of the range his variable should be tied to, then a lot of run time errors could never happen! Yes, it is the job of the programmer to avoid such errors. Today. As it was thirty years ago. But it shouldn't be! Of course, in many cases there is no need to check a variable's range, simply because it is being used inside a very limited scope. But even then the ability for simple range checking without added effort could help detect runtime errors! Stefan

3 2

[boost signal] Connecting while a notification is being processed
by Eric B 18 Aug '08

18 Aug '08

Hi I wonder what would happen (if) - while a signal is being processed - one of the listener method cause a new listener to connect to this signal Will the new listener append to the end of the listeners and therefore be called last ?

1 0

[boost]smart iterator
by Eduardo Panisset 18 Aug '08

18 Aug '08

Hi, Just for clarifying what I mean by "smart iterator": a smart iterator would be a iterator that acquires/releases locks on container/container items. If we would consider a Reader/Writer paradigm - few writtings and many readings, then a const_iterator would acquire/release a read lock on container and read lock on item, and a iterator would acquire/release a read lock on container and a write lock on item. For writting operations on container (e.g insert, remove), we would acquire write lock on container. Of course, we would consider a container stability, if stable (e.g. std::list, std::map) or unstable( e.g. std::vector, std::deque) in order to optimizing the solution (stable containers would allow simultaneous read/write operations on container). obs:Maybe the paradigm of concurrency could be a parameter. There is an analogous iterator in boost ? Thanks. Eduardo Panisset

1 0

AIX xlC error on static_move_ptr.hpp
by Gary Fu 18 Aug '08

18 Aug '08

Hi, Could anyone help why the AIX (5.3) xlC complains on the include file 'static_move_ptr.hpp' and how to solve the problem if possible ? I tried on Linux g++ without problem. Thanks, Gary 8:52pm > xlC -I $HOME/BOOST/boost_1_36_0 example.cpp -o example "/home_dir/Ggfu/BOOST/boost_1_36_0/boost/ptr_container/detail/static_move_ptr.hpp", line 182.22: 1540-2611 (S) The name "typename move_ptrs::enable_if_convertible<TT,T,boost::ptr_container_detail::static_move_ptr &>::type::type" can only be used to declare a constructor. #include <boost/ptr_container/detail/static_move_ptr.hpp> #include <iostream> #include <string> using namespace std; int main() { //print out the text string, "Hello, World!" cout << "Hello, World!" << endl; return 0; }

1 0

Re: [Boost-users] size_type doubts / integer library..
by Lang Stefan 18 Aug '08

18 Aug '08

Some thoughts: 1. Original problem Assigning a size to an ID type, IMHO appears to be completely unrelated to the general integral types' problem. There are two possibilities: A) you intend to use your ID to later reference some address or offset (which is the same) in memory. If that is your intention, then you should stick to the size type (i. e. std:size_t). Problem solved. B) if you don't intend to ever use your ID in the future to refer to an address in memory, then using an integral type might prove short-sighted. Unless you have a very concise knowledge about how many IDs you will need in, say, 5 years, or maybe 10 years from now, it's dangerous to limit yourself to a specific integral type for such a value. The least I would do is a typedef to hide the true type of that value and prevent anyone from making presumptions about it's potential size. Better yet define a class for this ID. If you do that you can write your own conversions and mathematical operators exactly the way you want them to be. Plus you have a central place to fix your conversions if you decide to change your ID class in a couple of years. Problem solved - in a very clean way. (IMHO) Then again I might be overestimating the importance and scope of this ID value. But in that case, why is 'unsigned long' the 'correct' type? Regarding this question, see my comments in part 3 of this message. 2. Size types (and difference types) I disagree on your complaint about size types all being unsigned. The quotation from B. Stroustrup explicitly made an exception for specific cases, and as I understand it he *was* referring to size types. The problem with size types is that they do need to be able to point to every location within the addressable memory space. Unfortunately this means they will need every single bit of the biggest data entity a CPU can handle at any one time. If size types were signed, they would need one extra bit for the sign, effectively doubling the amount of memory such a type would take up in memory. Unfortunately 'difference types' technically should be both signed and able to address every legal address in memory - which means one bit more than the current size types! However, see below.... 3. Integral types situation I agree with your general assessment of the integral types' situation. For several reasons actually, some of them not pointed out yet: A) Whenever signed and unsigend types are mixed, the compiler implicitly converts some of the values or intermediate results. Unfortunately it's often not obvious, which values and terms are being converted, and whether that can lead to problems. Most of the time (but not always, as you have correctly pointed out) the compiler issues warnings in such situations, but many compilers just point to the line, not the exact variable or term. B) What makes this problem even more difficult, is the widespread use of libraries, which may or may not use signed/unsigned values for specific properties, and thus don't even leave it open to the developers to avoid such combinations! C) Built-in integral types are based on internal representations of numbers. From the perspective of a designer this is just plain wrong! It is a violation of the principle of information hiding! Types shouldn't reveal anything about their internal representation, and after 20+ years of history in object oriented programming I really don't understand why we are still forced to use such types! When a developer selects an integral type for a variable, he considers the preconditions and postconditions, and decides the range of values his variable could legally assume. However, he shouldn't be forced to map this range to one of a few predefined ranges, just because these predefined ranges happen to fit the compiler's preferred internal representation. If a variable can assume values in the range [0..999999], then is 'long' the 'correct' type? Or is it 'unsigned long'? My answer is: neither! If the developer chooses either type, others looking at the code might not recognize that certain values outside that range (but well within the limits of the chosen type) will cause problems or might indicate an error elsewhere. 4. Resolution I like the suggestion of an integral type that is defined as a range of valid values. An additional (optional) parameter could be provided to define policies such as behavior on overflow, conversion problems and the like. This would be in the spirit of information hiding. In the case of size types or difference types, the address space could be reasonably restricted to a range that allows for a sign bit without compromising the maximum internal data size. In most cases anyway. And when it turns out an additional bit is still needed, then so be it! This design would take away the need to think in internal representations, and instead would allow the developers to concentrate on the true limitations of their variable types. 5. Advantages A) Developers can set more concise limits on their variables and behavior on violation of these limits. B) Predefined behavior on violations at runtime. C) Compiler developers can optimize internally needed storage by clustering mechanisms, depending on whatever memory access and processing capabilities the available cores provide. D) Compiler developers need to deal with just one basic integral class instead of a dozen or more. Depending on processor architecture this may or may not be very helpful (it might be neccessary to redefine the current integral types internally), but at least the use of these types would be more secure and less prone to programming errors. (Of course this implies the annihilation of current integral types which won't happen for some time, even after a standard basic adaptable integral type would be provided.) So these are my 5 cents, sorry for the lengthy post. Stefan

4 3

trunk documentation
by Felipe Magno de Almeida 18 Aug '08

18 Aug '08

Is there a link where I can access the generated trunk documentation? Thanks in advance, -- Felipe Magno de Almeida

5 6

Serialization in Bost 1.36
by Hansi 18 Aug '08

18 Aug '08

Hello, has the version used in boost 1.36 now the same features as the version on the homepage www.rrsd.com ? best regards Hansjörg

2 1

What should I do to switch my legacy application to use boost smart pointers
by Meryl Silverburgh 18 Aug '08

18 Aug '08

Hi, I have a legacy application in C++, and I would like to switch it to use boost smart pointers. Can you please tell me what is the best approach for the switch? This application uses stl vector as the class container, vector<MyClass*> function which takes in MyClass* void f1(MyClass* aMyClass) { ...} function which returns MyClass* MyClass* f1() { return new MyClass(); } I am thinking just global replace all MyClass* with MyClassPtr And then put in a common .h file typedef MyClassPtr shared_ptr<MyClass> Will this approach work? Thank you for any tips.

2 1

Boost and Eclipse Integration
by Amir Hossein Jadidinejad 18 Aug '08

18 Aug '08

Hi,I'm using "Eclipse IDE for C/C++ Developers" on Linux SUSE 10.3. How can I integrate boost programs with Eclipse.I used Visual Studio.Net 2008 previously and not familiar with eclipse. Help me please.Regard,----------------------------------- Amir Hossein Jadidinejad Master of Computer Science Islamic Azad University, Iran Home Page: http://jadidi.info E-Mail : amir(a)jadidi.info , amir.jadidi(a)yahoo.com

3 3

LNK2019: unresolved external symbol "int __cdecl test_main
by Ákos Maróy 18 Aug '08

18 Aug '08

Hi, I'm trying to compile a simple unit test using the boost unit test framework, using MS Visual Studio 2008. I can compile the same code on Linux using gcc just fine (and on Windows using MiGW as well, actually). But with Visual Studio, I get the following error: ------ Build started: Project: test, Configuration: Debug Win32 ------ Linking... LINK : warning LNK4098: defaultlib 'MSVCRT' conflicts with use of other libs; use /NODEFAULTLIB:library libboost_test_exec_monitor-vc90-mt-1_35.lib(test_main.obj) : error LNK2019: unresolved external symbol "int __cdecl test_main(int,char * * const)" (?test_main@@YAHHQAPAD@Z) referenced in function "public: void __thiscall test_main_caller::operator()(void)" (??Rtest_main_caller@@QAEXXZ) C:\var\VS_workspace\Debug\test.exe : fatal error LNK1120: 1 unresolved externals Build log was saved at "file://c:\var\VS_workspace\test\Debug\BuildLog.htm" test - 2 error(s), 1 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== this is despite the fact that I'm linking against libboost_test_exec_monitor-vc90-mt-1_35.lib, that would (?) include test_main. here's the Visual C++ linking command parameter list: /OUT:"C:\var\VS_workspace\Debug\test.exe" /INCREMENTAL /NOLOGO /LIBPATH:"C:\usr\boost_1_35_0\lib" /MANIFEST /MANIFESTFILE:"Debug\test.exe.intermediate.manifest" /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /DEBUG /PDB:"C:\var\VS_workspace\Debug\test.pdb" /SUBSYSTEM:CONSOLE /DYNAMICBASE /NXCOMPAT /MACHINE:X86 /ERRORREPORT:PROMPT libboost_unit_test_framework-vc90-mt-1_35.lib libboost_test_exec_monitor-vc90-mt-1_35.lib kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib this unit test sample app I'm trying to work on is very simple: #include <boost/test/unit_test.hpp> using namespace boost::unit_test; void test() { BOOST_CHECK(true); } test_suite * init_unit_test_suite(int, char **) { test_suite *ts = BOOST_TEST_SUITE("Test"); ts->add(BOOST_TEST_CASE(&test)); framework::master_test_suite().add(ts); return 0; } I wonder what I'm doing wrong... Akos

1 0

test
by Sergey Sadovnikov 18 Aug '08

18 Aug '08

Hello All, test -- Best Regards, Sergey mailto:flex_ferrum@artberg.ru

1 0

[Trac] Can not view tickets, can not report bug.
by John C. Femiani 18 Aug '08

18 Aug '08

I wanted to search tickets by library on the track site, but I got a trac error. The error had a link to create a ticket so I could report the Trac error to you guys, but then the ticket is rejected as SPAM! What am I to do? (I have another bug to report, but I can not even get far enough to see if the bug is already reported yet :-( ) When I submit the ticket, I get this message: Submission rejected as potential spam (Akismet says content is spam) Below is the ticket incorrectly reported as SPAM ==== How to Reproduce ==== While doing a GET operation on `/report/14`, Trac issued an internal error. '' Trac detected an internal error: ValueError: invalid literal for int(): '' Request parameters: {{{ {'id': u'14'} }}} User Agent was: `Opera/9.50 (Windows NT 5.1; U; en)` ==== System Information ==== || '''Trac''' || `0.11` || || '''Python''' || `2.4.4 (#1, Jan 25 2007, 13:04:51) ` [[br]] `[GCC 3.4.6 20060404 (Red Hat 3.4.6-3)]` || || '''setuptools''' || `0.6c8` || || '''SQLite''' || `3.5.4` || || '''pysqlite''' || `2.4.1` || || '''Genshi''' || `0.5` || || '''Subversion''' || `1.4.2 (r22196)` || || '''jQuery:''' || `1.2.3` || ==== Python Traceback ==== {{{ Traceback (most recent call last): File "/opt/trac2/lib/python2.4/site-packages/Trac-0.11-py2.4.egg/trac/web/main.py", line 423, in _dispatch_request dispatcher.dispatch(req) File "/opt/trac2/lib/python2.4/site-packages/Trac-0.11-py2.4.egg/trac/web/main.py", line 219, in dispatch data, content_type) File "/opt/trac2/lib/python2.4/site-packages/Trac-0.11-py2.4.egg/trac/web/chrome.py", line 726, in render_template stream.render(method, doctype=doctype, out=buffer) File "build/bdist.linux-i686/egg/genshi/core.py", line 179, in render File "build/bdist.linux-i686/egg/genshi/output.py", line 61, in encode File "build/bdist.linux-i686/egg/genshi/output.py", line 311, in __call__ File "build/bdist.linux-i686/egg/genshi/output.py", line 753, in __call__ File "build/bdist.linux-i686/egg/genshi/output.py", line 592, in __call__ File "build/bdist.linux-i686/egg/genshi/output.py", line 698, in __call__ File "build/bdist.linux-i686/egg/genshi/output.py", line 532, in __call__ File "build/bdist.linux-i686/egg/genshi/core.py", line 283, in _ensure File "build/bdist.linux-i686/egg/genshi/core.py", line 283, in _ensure File "/opt/trac2/lib/python2.4/site-packages/Trac-0.11-py2.4.egg/trac/web/chrome.py", line 779, in _strip_accesskeys for kind, data, pos in stream: File "build/bdist.linux-i686/egg/genshi/core.py", line 283, in _ensure File "/opt/trac2/lib/python2.4/site-packages/Trac-0.11-py2.4.egg/trac/web/chrome.py", line 768, in _generate for kind, data, pos in stream: File "build/bdist.linux-i686/egg/genshi/template/base.py", line 569, in _include File "build/bdist.linux-i686/egg/genshi/template/markup.py", line 299, in _match File "build/bdist.linux-i686/egg/genshi/template/markup.py", line 299, in _match File "build/bdist.linux-i686/egg/genshi/template/markup.py", line 246, in _match File "build/bdist.linux-i686/egg/genshi/template/base.py", line 543, in _exec File "build/bdist.linux-i686/egg/genshi/template/base.py", line 533, in _eval File "build/bdist.linux-i686/egg/genshi/template/base.py", line 496, in _eval File "build/bdist.linux-i686/egg/genshi/template/base.py", line 551, in _flatten File "build/bdist.linux-i686/egg/genshi/core.py", line 283, in _ensure File "build/bdist.linux-i686/egg/genshi/path.py", line 141, in _generate File "build/bdist.linux-i686/egg/genshi/template/base.py", line 569, in _include File "build/bdist.linux-i686/egg/genshi/template/markup.py", line 235, in _strip File "build/bdist.linux-i686/egg/genshi/template/base.py", line 543, in _exec File "build/bdist.linux-i686/egg/genshi/template/base.py", line 533, in _eval File "build/bdist.linux-i686/egg/genshi/template/base.py", line 496, in _eval File "build/bdist.linux-i686/egg/genshi/template/base.py", line 551, in _flatten File "build/bdist.linux-i686/egg/genshi/core.py", line 283, in _ensure File "build/bdist.linux-i686/egg/genshi/path.py", line 141, in _generate File "build/bdist.linux-i686/egg/genshi/template/base.py", line 569, in _include File "build/bdist.linux-i686/egg/genshi/template/markup.py", line 235, in _strip File "build/bdist.linux-i686/egg/genshi/template/base.py", line 543, in _exec File "build/bdist.linux-i686/egg/genshi/template/base.py", line 520, in _eval File "build/bdist.linux-i686/egg/genshi/template/base.py", line 286, in _eval_expr File "build/bdist.linux-i686/egg/genshi/template/eval.py", line 180, in evaluate File "/opt/trac2/lib/python2.4/site-packages/Trac-0.11-py2.4.egg/trac/ticket/templates/report_view.html", line 120, in <Expression u"cell.value != 'None' and format_date(int(cell.value)) or '--'"> <td class="date" py:attrs="td_attrs">${cell.value != 'None' and format_date(int(cell.value)) or '--'} ValueError: invalid literal for int(): }}}

2 1

[swap] How to override swap now?
by Terry G 18 Aug '08

18 Aug '08

I notice that Boost now has it's own boost::swap and that it has had recent trouble before the 1.36 release. How should a user/developer like me implement a custom swap so that users get the benefit of my::swap, then boost::swap, and finally std::swap without putting too much burden on my user. So I have three questions. (1) How should user-code use boost:swap? (2) How should boost-developers use boost::swap()? (3) How should non-boost-developers provide swap()? Consider my motivating (to me) example... Let's say I have a move library that works, hypothetically. namespace my { // These are defined and actually work, hypothetically. template <class T> struct is_moveable; template <class T> struct move_from { }; template <class T>T& move(T& x); template <class T> void swap(T& x, T& y) { T tmp = move(x); x = move(y); y = move(tmp); } // swap } // namespace my If the user does this... using namespace std; using namespace boost; using namespace my; And then somewhere in his code... HisType a = MakeA(); HisType b = MakeB(); swap(a, b); // Unqualified? Or should the user specify a namespace? Which one? What I wish would happen would be... If the user has his own swap(HisType, HisType) invoke that. Otherwise, if HisType.swap() exists, then use that. Otherwise, use my::swap() if its "better" than boost::swap Otherwise, use boost::swap(), if its "better" than std::swap Otherwise, just use std::swap(). Sorry about all the ambiguity. But that's the real problem, isn't it? terry

2 1

[function_types] Removing class type from member function signature.
by Fabio Fracassi 18 Aug '08

18 Aug '08

Hi, I'm currently trying to wrap (or forward) a call to boost::signal<A_func_Signature>::connect(), to - amongst other things - insulate users from using boost::bind. So what I have is something like this: template< typename Signature, class Reciever > void connect( const signal_id& id, const Signature& sig, const Reciever* rcv ) { typedef ???? AdaptedSignature; get_signal< AdaptedSignature > ( id ) -> connect(boost::bind(sig, rcv, _1)); } now this code is supposed to be called like this: connect( some_signal_id, &SomeClass::some_member, someClass_instance ); where SomeClass::some_member has the same function signature as the signal which is associated with some_signal_id. e.g. boost::signal<void (bool)> signal; struct SomeClass { void some_member(bool b); }; So my question is how can I construct the "AdaptedSignature" type from the template deduced "Signature"? From what I gather from the documentation, boost function_types might hold the answer to my question, but I cannot figure out how. So is what I am trying to do possible, and is function_types the right tool? TIA Fabio

1 0

[scoped_ptr] Transferring pointers to scoped_ptr member
by Christian Larsen 18 Aug '08

18 Aug '08

Hi, This is just make sure I'm not being too careful in this situation. So please confirm whether this is correct. I have a class with two scoped_ptr members, and I want to pass two pointers to the constructor, which will then transfer the ownership of both to the two member scoped_ptrs. I assume the following is not safe: (I didn't try compiling; using namespace boost and std.) struct B {}; class A { public: A(B* b1, B* b2) : b1_(b1), b2_(b2) {} private: scoped_ptr b1_; scoped_ptr b2_; }; // Create an A this way: A a(new B, new B); Is it correct that this could fail if one of the 'new B's throw, thus leaking before the constructor ever started? If that is so, is this then the correct way to achieve the same in a safe manner? struct B {}; class A { public: A(auto_ptr& b1, auto_ptr& b2) : b1_(b1.release()), b2_(b2.release()) {} private: scoped_ptr b1_; scoped_ptr b2_; }; // Create an A this way: A a(auto_ptr(new B), auto_ptr(new B)); Best regards, Christian

3 6

[python] partially resolved: the never ending story of vc8/win32 linker settings desaster
by Markus Werle 18 Aug '08

18 Aug '08

Hi! So now since I wasted 2 days figuring out the interaction of Python with boost::python and Visual Studio 2005 SP1 (VC8) I finally managed to resolve the "VC8/Debug Crashes" problem. To be honest: I am shocked and I need someone to explain why things are intentionally broken the way they are. All boost libraries play nicely with *any* build system, but the settings for Boost.Python are twisted in ways that make me feel absolutely uncomfortable. Admittedly some of the headaches have their reason inside Python itself and somehow Visual Studio plays ugly, too, but IMHO it is time to rework the settings shipped with Boost.Python. I managed to resolve some of the troubles I had with VS2005. If you try to run a debug version of Boost.Python with Debug-Python you are on your own: Boost.Python(Debug) deliberately links to Python(Release) which is the source of major headache: 1. With VS2005 it is NOT a GoodIdea(TM) to mix different types of binaries for one executable, since the (stupid) linker of vs2005 succeeds without error sometimes creating executables that fail to be debugged and/or crash at random points during execution. Summary: VC8 linker sucks in many aspects, so don't do that. This is a request to change the settings of the debug version Boost.Python, even if this forces the user to download the python sources. What do you think? 2. You can, of course, build Python with _DEBUG settings. This again breaks everything: Python-2.5.2, sets Py_DEBUG and then in file Include/object.h, line 58 decides that 54 /* Py_DEBUG implies Py_TRACE_REFS. */ 55 #if defined(Py_DEBUG) && !defined(Py_TRACE_REFS) 56 #define Py_TRACE_REFS // WE HAVE A PROBLEM HERE!!!!!!!! 57 #endif Autodefined Py_TRACE_REFS itself yields Py_InitModule4 be renamed to Py_InitModule4TraceRefs in modsupport.h: #ifdef Py_TRACE_REFS /* When we are tracing reference counts, rename Py_InitModule4 so modules compiled with incompatible settings will generate a link-time error. */ ... #define Py_InitModule4 Py_InitModule4TraceRefs #endif Unfortunately two things lead to a headache here: First, boost::python::detail::init_module *always* calls Py_InitModule4 regardless of the compiler settings, which I consider critical here. See libs/python/src/module.cpp for what I mean. Second, vc8 linker - for reasons beyond my limited horizon - during search of symbols in my self-created python_d.lib/dll fails to find Py_InitModule4, requested by boost::python::detail::init_module, but happens to find python.lib/dll in the same directory and (BOOM) silently links against python.lib/dll (OUCH!) which yields a truly broken executable, the nightmare of debugging stuff that should not have compiled. I suspect Boost.Python settings to be resposible for this. Please correct me if I am wrong here (of course I may have missed something): Summary so far: If you want to debug an embedded Boost.Python/Python with vc8 you have to fetch the Python sources, change file Include/object.h, line 56 such that 54 /* Py_DEBUG implies Py_TRACE_REFS. */ 55 #if defined(Py_DEBUG) && !defined(Py_TRACE_REFS) 56 // #define Py_TRACE_REFS // WE HAVE A PROBLEM HERE!!!!!!!! 57 #endif then after rebuilding the "Debug" version of PCbuild8\pcbuild.sln go to your own project, Open the project settings linker settings and add python.lib to the "Ignore Specific Library" section. Copy the python_d.dll and .lib files to your project and everything is fine. Phew. Done. Compiles. Runs. Does not Crash. Don't you think we can do better? IMHO the content of libs/python/src/module.cpp belongs into a header that allows users to control its behaviour and that nicely interacts with the original Pythion settings. To be resolved: I failed to create a static executable that statically links to boost::python and Python, since boost::python static libs ask for python.lib/dll symbols beginning with __imp__ instead of taking those in my self-named libpython-mt-sgd.lib. Can you provide a resolution for this task? Boost.Build settings? Wrong library included? Markus

3 7

Filesystem, serialization, character encoding and portable software
by Mathieu Peyréga 18 Aug '08

18 Aug '08

Hello, I'm currently writting an open source and portable (Win32 / OS X / Linux) software, and i'm using parts of boost libraries, especially for the issue described here : - boost serialization - boost filesystem At some point, i'm storing a directory name (as a std::string) into a xml file through boost serialization library. The encoding occurs on a windows platform, and as far as i can understand (i'm really new to all these character set issues) it seems to be done in win1252 character set. One of the directory "stored" is named "français" (notice the cedilla on the c) and is the issue.. When i load this file back on a linux or osx platform, and try to access files in the "français" directory, i got an error of the kind (no such directory)... because the encoding of the ç with cedilla seem to be wrong... (everythong works fine if i put "francais" everywhere without cedilla) Is there somewhere a good starting document for character set for dummies with tutorials or stuff like that ? How would you suggest i correct the issue (while keeping the "ç") ? Altought, I understand this is not completely boost issue... But it seems to have so many "hidden" functions that i'm wondering if the libraries would have something to do that that i missed... Regards, Mathieu -- http://www.incub.net/

4 5

Boost 1.36.0 release notice
by Beman Dawes 18 Aug '08

18 Aug '08

Boost 1.36.0 has been released and is available from SourceForge. See http://sourceforge.net/projects/boost/ This release include four new libraries: * Accumulators: Framework for incremental calculation, and collection of statistical accumulators, from Eric Niebler. * Exception: A library for transporting of arbitrary data in exception objects, and transporting of exceptions between threads, from Emil Dotchevski. * Units: Zero-overhead dimensional analysis and unit/quantity manipulation and conversion, from Matthias Schabel and Steven Watanabe * Unordered: Unordered associative containers, from Daniel James. Updated libraries include Asio, Assign, Function, Hash, Interprocess, Intrusive, Math, MPI, Multi-index Containers, PtrContainer, Spirit, Thread, Wave, and Xpressive. The release managers were Beman Dawes, Rene Rivera, and Daniel James. One note of caution: the initial SourceForge release files were missing some of the documentation. If you downloaded before 16:00 UTC, August 14th, please download again to be sure to get the full distribution. Sorry for the inconvenience! --Beman Dawes PS: The 1.36.0 version of the web site should be up within a few hours. If you can't wait, see http://beta.boost.org now!

4 7

[filesystem] convenience_test.cpp question
by Olaf Peter 18 Aug '08

18 Aug '08

Hi, on studying the boost's files I found in convenience_test.cpp this statement: BOOST_CHECK( fs::extension("a/") == "." ); Why this? IMO it's not clear why this should be correct. This means that a leaf path has a file extension. On directory's view this is not equal to the current dir notation. Thanks, Olaf BTW, what about the support on hard- and softlinks mentioned in this list some times ago?

2 2

[filesystem] Changes in Boost 1.36 not documented?
by Anteru 18 Aug '08

18 Aug '08

Hi, I've just upgraded to Boost 1.36, and I had to change some code because the directory iterators ->leaf () function has changed. Looking at the docs (http://www.boost.org/doc/libs/1_36_0/libs/filesystem/doc/index.htm#Change-h…) there is no information what has changed in 1.36 and how to port 1.35 code over to it. Is this information available somewhere else? Cheers, Anteru

2 1

[filesystem] compiling code breaks on 1.36
by Scott Finley 18 Aug '08

18 Aug '08

I am on ubuntu 8.04. When upgrading from 1.34.1 to 1.36 the following code breaks. bfs_test.cpp: #include <iostream> #include <boost/filesystem.hpp> using std::cout; using std::endl; namespace bfs = boost::filesystem; int main() { bfs::recursive_directory_iterator end_itr; for( bfs::recursive_directory_iterator itr( "." ); itr != end_itr; ++itr ) { cout << bfs::extension( itr->leaf() ) << endl; } return 0; } I compile for 1.34.1 like this: gcc -o bfs bfs_test.cpp -lstdc++ -lboost_filesystem-gcc41-mt-1_34_1 running the result prints all file extensions recursively as expected. After switching to 1.36 compiling like this: gcc -o bfs bfs_test.cpp -lstdc++ -lboost_filesystem-gcc42-mt-1_36 gives the following error: bfs_test.cpp: In function 'int main()': bfs_test.cpp:13: error: 'class boost::filesystem::basic_directory_entry<boost::filesystem::basic_path<s td::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::filesystem::path_traits> >' has no member named 'leaf' My mistake, or did something change/break? Scott Finley

3 2

building and calling "dynamic c++" from a host program
by Isaac Lascasas 17 Aug '08

17 Aug '08

Hello I have the following question: If you want to make a program that will let the user write "scripts" directly in c++, how will you do it? I am strugling my mind these days looking for a solution to this problem and I want to know if boost already address this situation. My intuition tells me that the process will probably consist on invoking bjam to build a dynamic lib with the "script" and then call the built code in the host binary. But how can this be done keeping it portable and clean? Obviously it won't work if you don't have a build environment configured but anyway it may be a very interesting feature. Regards, Isaac Lascasas.

5 6

shared_ptr race condition
by Eduardo Panisset 17 Aug '08

17 Aug '08

Hi, I have studied the sp_counted_base implementation and I can't see how it is trade safe. For instance: bool add_ref_lock() // true on success { pthread_mutex_lock( &m_ ); bool r = use_count_ == 0? false: ( ++use_count_, true ); pthread_mutex_unlock( &m_ ); return r; } void release() // nothrow { pthread_mutex_lock( &m_ ); long new_use_count = --use_count_; pthread_mutex_unlock( &m_ ); if( new_use_count == 0 ) { dispose(); weak_release(); } } I suppose to exist a race condition because I can't execute the comparation "if( new_use_count) == 0" outside of critical region delimited by mutex. So if: 1. Reference count = 1 2. Thread A executes release and is interrupted after execute the comparation if( new_use_count) == 0 (the comparation returns true) 3. Thread B executes add_ref_lock, then Ref count = 1 4. Thread A executes "dispose()" and releases the pointer ! What Do you think about ? Eduardo Panisset.

5 15

Building boost with codegear rad studio 2007
by Sean Farrow 16 Aug '08

16 Aug '08

Hi: Has any one built boost 1.36 with codegear rad studio 2007. I there a codegear.jab file. Is not what would I do to create one? Cheers Sean. __________ Information from ESET NOD32 Antivirus, version of virus signature database 3357 (20080814) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

5 12

Re: [Boost-users] user-config.jam settings for building boost::MPI on windows Intel? (and potential bug in 1.36)
by Jesse Perla 16 Aug '08

16 Aug '08

* Here was my user-config.jam to install with MPICH2, windows Intel:using intel-win ; using mpi : : <find-shared-library>cxx <find-shared-library>mpi <library-path>C:/apps/MPICH2/lib ; * Considering that MPICH2 is a common library, perhaps it is worth the automatic mpi search on windows to look for it instead of just windows compute cluster. Sadly, I don't know enough about jam to write it myself. Now for a potential build issue: * After running: *bjam release debug --with-mpi *I then copied the libs/dll's into a lib folder in my Lib path for the compiler. * The build created a file called: libboost_mpi-iw-mt-gd-1_36.lib * And it created a file called: boost_serialization-iw-mt-gd-1_36.lib * However, when I tried to build using Intel C++ (and I didn't add the libs directly into the link inputs, the boost::mpi figured it out itself), it found the MPI library file, but tried to automatically look for a library called: libboost_serialization-iw-mt-gd-1_36.lib instead of the one created. * I renamed the serialization library to have "lib" in front, and everything compiled/ran fine. * * On Fri, Aug 15, 2008 at 2:23 PM, Jesse Perla <jesseperla(a)gmail.com> wrote: > I am trying to build the boost::mpi (1.36) on: > 1) Windows vista > 2) Visual Studio 2008 > 3) Intel C++ 10.1 (though could switch to the built in Microsoft compiler > here if it would help) > 4) With the open source MPICH2 libraries installed. > > I can link, compile, and test properly according to the beginning of the > MPI > intstructions ( > http://www.boost.org/doc/libs/1_35_0/doc/html/mpi/getting_started.html) > > Now, I added "using intel ; " and "using mpi ; " to my user-config.jam, but > > I guess it can't autodetect since it spits out: > > C:\apps\boost\boost_1_36_0>bjam --with-mpi > > The system cannot find the path specified. > > The system cannot find the path specified. > > The system cannot find the path specified. > > MPI auto-detection failed: unknown wrapper compiler mpic++ > > > > > > Does anyone know the set of config settings that would work for the setup I > described? When I tried to get debugging info out of the build, it said something > about trying to detect windows cluster server, which I am not using > (instead, MPICH2 as above). > > I guess part of the question is whether Intel C++ needs a "wrapper > compiler" as discussed later in the getting started. Since I was able to > compile and run the (non boost) MPI code, it doesn't seem so to me. > (or are there binaries for the MPI libraries? I had trouble finding them...) > > > Thanks, > Jesse >

1 0

Compiling from source - boost on Ubuntu AMD64
by Simon Pickles 16 Aug '08

16 Aug '08

Hi, Are there any requirements for building boost from source on Ubuntu AMD64? Do I need to pass any -m64 or -fPIC flags? Many thanks Simon

1 0

boost 1.34.1 build failed with segfaulting bjam using gcc4.2.3
by François Mauger 16 Aug '08

16 Aug '08

Hi boosters I just tried to build boost 1.34.1 from source on my laptop running Linux Ubuntu 8.04 and gcc version 4.2.3. Unfortunately it failed at the very beginning: $ ./configure --prefix=/scratch/sw/boost/install-1_34_1-gcc42 \ --with-libraries=date_time,filesystem,\ iostreams,program_options,python,serialization,thread #!!! ---> here the bjam binary is built Building Boost.Jam with toolset gcc... tools/jam/src/bin.linuxx86/bjam Detecting Python version... 2.5 Detecting Python root... /usr Unicode/ICU support for Boost.Regex?... /usr Backing up existing Boost.Build configuration in user-config.jam.1 Generating Boost.Build configuration in user-config.jam... Generating Makefile... $ make ./tools/jam/src/bin.linuxx86/bjam -sICU_PATH=/usr --user-config=user-config.jam --with-date_time --with-filesystem --with-iostreams --with-program_options --with-python --with-serialization --with-thread Segmentation fault <=== BLAM! strace output that prints: >>>>>>> $ strace tools/jam/src/bin.linuxx86/bjam execve("tools/jam/src/bin.linuxx86/bjam", ["tools/jam/src/bin.linuxx86/bjam"], [/* 236 vars */]) = 0 brk(0) = 0x8071000 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) mmap2(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7fb8000 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7fb7000 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7fb6000 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory) ... open("/etc/ld.so.cache", O_RDONLY) = 3 fstat64(3, {st_mode=S_IFREG|0644, st_size=66160, ...}) = 0 mmap2(NULL, 66160, PROT_READ, MAP_PRIVATE, 3, 0) = 0xb7fa5000 close(3) = 0 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) open("/lib/tls/i686/cmov/libc.so.6", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\260e\1"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0755, st_size=1364388, ...}) = 0 mmap2(NULL, 1369712, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7e56000 mmap2(0xb7f9f000, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x149) = 0xb7f9f000 mmap2(0xb7fa2000, 9840, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb7fa2000 close(3) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7e55000 set_thread_area({entry_number:-1 -> 6, base_addr:0xb7e556b0, limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, seg_not_present:0, useable:1}) = 0 mprotect(0xb7f9f000, 4096, PROT_READ) = 0 munmap(0xb7fa5000, 66160) = 0 time(NULL) = 1218843031 brk(0) = 0x8071000 brk(0x8092000) = 0x8092000 open("/etc/localtime", O_RDONLY) = 3 fstat64(3, {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 fstat64(3, {st_mode=S_IFREG|0644, st_size=2945, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7fb5000 read(3, "TZif2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\f\0\0\0\f\0\0"..., 4096) = 2945 _llseek(3, -28, [2917], SEEK_CUR) = 0 read(3, "\nCET-1CEST,M3.5.0,M10.5.0/3\n", 4096) = 28 close(3) = 0 munmap(0xb7fb5000, 4096) = 0 uname({sys="Linux", node="mauger-laptop", ...}) = 0 brk(0x80b3000) = 0x80b3000 brk(0x80d4000) = 0x80d4000 brk(0x80f5000) = 0x80f5000 --- SIGSEGV (Segmentation fault) @ 0 (0) --- +++ killed by SIGSEGV +++ Process 6883 detached <<<<<<<<<<<<<<<< I'm not familiar with the 'strace' utility so I cannot guess whatever useful from this output. So my pb comes from the brand new bjam executable (tools/jam/src/bin.linuxx86/bjam) that segfaults systematically for some mystery reason. Using bjam from the 'bjam' Debian package is ok so I can of course use the '--with-bjam=/usr/bin/bjam' switch to build the whole boost stuff. But I'm not satisfied with this solution for the standard boost build procedure worked perfectly as expected for boost 1.34.1 under my previous Ubuntu 7.04/gcc 4.1 and also for the new boost 1.36.0/gcc 4.2.3. Maybe someone could give me some hints to understand this problem? thanks a lot regards frc -- Francois Mauger Laboratoire de Physique Corpusculaire de Caen et Universite de Caen

2 1

namespace and directory name choice
by Hicham Mouline 16 Aug '08

16 Aug '08

hello, technically, this is not a boost question. I am writing a library to be used by third-party developers. Internally, i use boost::mpl sequences. Joaquin wrote mpl sequences cross-product metafunctions that i use, i called them sequence2_cross_product and sequence3_cross_product for the x-product of 2 and 3 sequences. I put the metafunction in a separate header file. I don't intend to expose it to my clients. Is there an agreed convention/style as to where such a header file should lie? My namespace hierarchy reflects my directory structure, so this is like asking in which namespace should i put this metafunction. I would have like to see such metafunctions already in boost::mpl., so should/can i highjack boost::mpl namespace in my header? or put it at toplevel right below my namespace ? rds,

3 2

Re: [Boost-users] [boost] Boost 1.36.0 release notice
by David Abrahams 15 Aug '08

15 Aug '08

on Fri Aug 15 2008, Stefan Seefeld <seefeld-AT-sympatico.ca> wrote: > David Abrahams wrote: >> on Fri Aug 15 2008, Stefan Seefeld <seefeld-AT-sympatico.ca> wrote: >> >> >>> Why can't the packaging process be automatized, making it fully >>> reproducible ? Trying to increase the amount of tests run on the final >>> package attacs the problem from the wrong end, IMO. >>> >> >> reproducability != correctness. >> >> I agree that automation is a good idea, but it might also be a good idea >> to test the results of that automation, neh? >> > Indeed. My point, however, was that I would *first* automatize, *then* > validate. The point of reproducibility is to cut down on the amount of > (repeated) validation you have to do afterwards, no ? :-) Makes sense to me. -- Dave Abrahams BoostPro Computing http://www.boostpro.com

1 0

Re: [Boost-users] [boost] Boost 1.36.0 release notice
by David Abrahams 15 Aug '08

15 Aug '08

on Fri Aug 15 2008, Stefan Seefeld <seefeld-AT-sympatico.ca> wrote: > Why can't the packaging process be automatized, making it fully > reproducible ? Trying to increase the amount of tests run on the final > package attacs the problem from the wrong end, IMO. reproducability != correctness. I agree that automation is a good idea, but it might also be a good idea to test the results of that automation, neh? -- Dave Abrahams BoostPro Computing http://www.boostpro.com

1 0

[Thread] Resetting interruption request
by Christian Larsen 15 Aug '08

15 Aug '08

Hello, I'm afraid this is a frequently asked question, but my attempts at searching have not been successful. My question is whether there is a smarter way to reset the interruption request (if any) than this: try { boost::this_thread::interruption_point(); } catch (boost::thread_interrupted&) { // ignore } Which I find a little messy for what I want to achieve. I'm using version 1.35.0. Best regards, Christian Larsen

2 4

recursive_timed_mutex::timed_lock()
by Eduardo Tavares 15 Aug '08

15 Aug '08

Hello ALL, I'm having problems using recursive_timed_mutex::timed_lock() on Linux -- an assertion failure occurs at line 171 (thread/pthread/recursive_mutex.hpp) : pthread_mutex_timedlock() returns ETIMEDOUT instead of expected EBUSY. After some hours of headache I checked out it's cousin -- mutex::timed_lock() -- and realized the (in my opinion) correct implementation. Is it a bug in recursive_timed_mutex.hpp ? Thanks in advance. Eduardo Tavares.

2 1

Thread example using a function object and using the return value
by Stephen Torri 15 Aug '08

15 Aug '08

I would like to have a function object that I can use the return value of its operator() function. Here is what I think best explains my request class Apple { public: int operator()( int x ) { int value = x * 2; return value; } } void main (int, char**) { int thread_count = 2; // 2-Core cpu // Create a pool of Apple threads typedef boost::shared_ptr<boost::thread> Thread_Ptr_t; typedef std::list < Thread_Ptr_t > Thread_Pool_t; Thread_Pool_t m_thread_pool; // Create threads for ( int index = 0; index < thread_count; ++index ) { Thread_Ptr_t new_thread_ptr ( new boost::thread ( boost::bind ( &Apple, _1, )( index ) ) ); m_thread_pool.push_back ( new_thread_ptr ); } // Wait for all threads to finish for ( Thread_Pool_t::iterator pos = m_thread_pool.begin(); pos != m_thread_pool.end(); ++pos ) { (*pos)->join(); } } Where is the point I should be catching return from the operator() function? I want the thread to do work and then have the opportunity to get some results from it. Is there a code example someone can show me? Stephen

2 1

user-config.jam settings for building boost::MPI on windows Intel?
by Jesse Perla 15 Aug '08

15 Aug '08

I am trying to build the boost::mpi (1.36) on: 1) Windows vista 2) Visual Studio 2008 3) Intel C++ 10.1 (though could switch to the built in Microsoft compiler here if it would help) 4) With the open source MPICH2 libraries installed. I can link, compile, and test properly according to the beginning of the MPI intstructions ( http://www.boost.org/doc/libs/1_35_0/doc/html/mpi/getting_started.html) Now, I added "using intel ; " and "using mpi ; " to my user-config.jam, but I guess it can't autodetect since it spits out: C:\apps\boost\boost_1_36_0>bjam --with-mpi > The system cannot find the path specified. > The system cannot find the path specified. > The system cannot find the path specified. > MPI auto-detection failed: unknown wrapper compiler mpic++ > > Does anyone know the set of config settings that would work for the setup I described? When I tried to get debugging info out of the build, it said something about trying to detect windows cluster server, which I am not using (instead, MPICH2 as above). I guess part of the question is whether Intel C++ needs a "wrapper compiler" as discussed later in the getting started. Since I was able to compile and run the (non boost) MPI code, it doesn't seem so to me. (or are there binaries for the MPI libraries? I had trouble finding them...) Thanks, Jesse

1 0

Pooling for fragmentation problem
by rottyguy 15 Aug '08

15 Aug '08

Hi, I am new to boost and was looking for a little guidance in using the right pool classes to help me with memory fragmentation. I have a hash_map indexed by a std::string --> smart_ptr<bufferObject> where bufferObject is a struct that holds a dynamically created char[] buffer and length integer. As this hash_map will hold millions of records (gigabytes of data), there will be plenty of objects created/destroyed many times over the amount of memory available to the system. I would like to employ a recyclable memory pool (to combat memory fragmentation). Here are my dynamic objects: key - std:string --> allocates based on a given string during an insert (a few 100 bytes to 2k max) value - bufferObject --> allocated to be held by the smart_ptr. bufferObject, itself, will hold dynamically allocated data. These bytes can range from a few hundred bytes to 4k max hash_map - millions of these key/value pairs created/destroyed. various vectors that are used throughout to copy over portions of the cache for retrieval. Any guidance is appreciated. TIA

1 0

mpl
by Hicham Mouline 15 Aug '08

15 Aug '08

hello, relating to my earlier post, the code for the 2-seq and 3-seq cross product is: #include <boost/mpl/pair.hpp> #include <boost/mpl/placeholders.hpp> #include <boost/mpl/fold.hpp> #include <boost/mpl/vector/vector10.hpp> #include <boost/mpl/copy.hpp> #include <boost/mpl/transform.hpp> namespace mpl = boost::mpl; using namespace mpl::placeholders; template <typename T> struct pair_with : mpl::pair<T, _> {}; template <typename pair> struct triple_with : mpl::vector3<typename pair::first, typename pair::second, _> {}; // public metafunction template<typename Sequence1, typename Sequence2> struct sequence2_cross_product : mpl::fold< Sequence1, mpl::vector0<>, mpl::copy< mpl::transform< Sequence2, pair_with<_2> >, mpl::back_inserter<_1> > > {}; template< typename SequencePair, typename Sequence> struct seq_seqpair_product : mpl::fold< SequencePair, mpl::vector0<>, mpl::copy< mpl::transform< Sequence, triple_with<_2> >, mpl::back_inserter<_1> > > {}; // public metafunction template<typename Sequence1,typename Sequence2,typename Sequence3> struct sequence3_cross_product : seq_seqpair_product< typename sequence2_cross_product<Sequence1,Sequence2>::type, Sequence3> {}; usage is like: S1: any MPL sequence with T11, T12, T13...T1k types S2: any MPL sequence with T21, T22, T23...T2m types S3: any MPL sequence with T31, T32, T33...T3n types typedef sequence2_cross_product<S1, S2>::type binary_product; /* this will be a mpl::vector< pair<T11, T21>, pair<T11, T22>, ... pair<T11, T2m>, pair<T12, T21>, pair<T12, T22>, ... pair<T1k, T2m> > */ // and typedef sequence3_cross_product<S1, S2, S3>::type ternary_product; /* this will be same mpl::vector, but with vector3<T11, T21, T31> ..... instead */ 1) I'm trying to make these metafunctions general enough, perhaps in the future i might use them for something i'm not thinking about now.... i would like to let the caller (me), choose what tuple/template to embed the resulting Tij, Tkl in... . for the sequence2_cross_product metafunction, mpl::pair, or mpl::vector2 or any class template that takes 2 type template arguments, or i could restrict the user to something that interacts well with mpl, is it "lambda expressions" or "metafct" or "metafct class"? . for the sequence3_cross_product metafunction, mpl::vector3 or any class template that takes 3 type template args... same question 2) I have a class template RT (not metafct or metafct class), that takes 3 template args, for each of these args, i have a list of possible types (in an mpl sequence), then i have a class R. I would like to define 2.1. typedef boost::variant< R, RT<T11, T21, T31>, RT<T11, T21, T32>.... > R; 2.2. do an explicit template instantiation of all the RT<..,..,..> Should i use Boost.PP for this, e.g.: #include <boost/preprocessor/seq/for_each_product.hpp> #include <boost/preprocessor/seq/enum.hpp> #define Type1 (T11)(T12)(T13)...(T1k) #define Type2 (T21)(T22)(T23)...(T2k) #define Type3 (T31)(T32)(T33)...(T3k) #define M(r, product) template class RT<BOOST_PP_SEQ_ENUM(product)>; BOOST_PP_SEQ_FOR_EACH_PRODUCT(M, (Type1)(Type2)(Type3)) #undef Type1 #undef Type2 #undef Type3 #undef M and what about variant<...>, how would i write it with PP? comment, thoughsts are appreciated, thanks, regards,

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New compiler warnings triggered by Boost 1.36
by cowwoc 15 Aug '08

15 Aug '08

When I compile my code against Boost 1.36 I get: 3>C:\Program Files\boost_1_36_0\boost/config/abi_prefix.hpp(19) : warning C4103: 'c:\program files\boost_1_36_0\boost\config\abi_prefix.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>C:\Program Files\boost_1_36_0\boost/thread/exceptions.hpp(22) : warning C4103: 'c:\program files\boost_1_36_0\boost\thread\exceptions.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>C:\Program Files\boost_1_36_0\boost/config/abi_suffix.hpp(20) : warning C4103: 'c:\program files\boost_1_36_0\boost\config\abi_suffix.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>C:\Program Files\boost_1_36_0\boost/thread/exceptions.hpp(108) : warning C4103: 'c:\program files\boost_1_36_0\boost\thread\exceptions.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>C:\Program Files\boost_1_36_0\boost/config/abi_prefix.hpp(19) : warning C4103: 'c:\program files\boost_1_36_0\boost\config\abi_prefix.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>c:\program files\boost_1_36_0\boost\thread\win32\thread_primitives.hpp(151) : warning C4103: 'c:\program files\boost_1_36_0\boost\thread\win32\thread_primitives.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>C:\Program Files\boost_1_36_0\boost/config/abi_suffix.hpp(20) : warning C4103: 'c:\program files\boost_1_36_0\boost\config\abi_suffix.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>c:\program files\boost_1_36_0\boost\thread\win32\thread_primitives.hpp(396) : warning C4103: 'c:\program files\boost_1_36_0\boost\thread\win32\thread_primitives.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>C:\Program Files\boost_1_36_0\boost/config/abi_prefix.hpp(19) : warning C4103: 'c:\program files\boost_1_36_0\boost\config\abi_prefix.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>c:\program files\boost_1_36_0\boost\thread\win32\interlocked_read.hpp(14) : warning C4103: 'c:\program files\boost_1_36_0\boost\thread\win32\interlocked_read.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>C:\Program Files\boost_1_36_0\boost/config/abi_suffix.hpp(20) : warning C4103: 'c:\program files\boost_1_36_0\boost\config\abi_suffix.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) 3>c:\program files\boost_1_36_0\boost\thread\win32\interlocked_read.hpp(78) : warning C4103: 'c:\program files\boost_1_36_0\boost\thread\win32\interlocked_read.hpp' : alignment changed after including header, may be due to missing #pragma pack(pop) I don't recall seeing this in 1.35 and I compiled against it two days ago. I am compiling under Visual Studio 2008, in x64 mode. How do I fix these warnings? Thank you, Gili -- View this message in context: http://www.nabble.com/New-compiler-warnings-triggered-by-Boost-1.36-tp18994… Sent from the Boost - Users mailing list archive at Nabble.com.

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[serialization] using serialization in shared library plugin
by Mojmir Svoboda 15 Aug '08

15 Aug '08

hello, i have big problem using boost::serialization under windows xp (vs2005sp). the thing is: there is a main application and there are .dll as plugins. i'd like to use boost::serialization from within the plugin, but i get segmentation faults immeadiately when boost_serialization.*.dll is loaded into memory. i traced it to some static_register and then i lost the trace. my guess is that the library tries to allocate some memory, but our own allocator is not loaded and initialized yet... do you have, please, some recommendations how to use the serialization in this way? many thanks in advance, mojmir

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[filesystem] major problem with 1.36 on OS X
by Matthias Schabel 15 Aug '08

15 Aug '08

Attempting to compile and link the following code with a default build of 1.36 on OS X 10.5.4 (Intel) // test.cpp #include <fstream> #include <iostream> #include <string> #include <vector> //#include <boost/system/error_code.hpp> //#include <boost/system/system_error.hpp> #include <boost/filesystem/operations.hpp> #include <boost/filesystem/path.hpp> int main (int argc, char * const argv[]) { boost::filesystem::create_directory("blah"); return 0; } results in a linker error, even though the method in question is defined inline in <boost/system/error_code.hpp> : Undefined symbols: "boost::system::error_code::message() const", referenced from: boost::system::system_error::what() constin ccyMBSNr.o ld: symbol(s) not found collect2: ld returned 1 exit status This is reproducible both from a clean XCode 3.0 project and from the command line : gcc test.cpp -I/usr/local/include -I .. -L/usr/local/lib - lboost_filesystem-xgcc40-mt -lboost_system-xgcc40-mt -lstdc++ Uncommenting the explicit includes doesn't help, either. This is a weird one... Matthias

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Thoughts & questions on adding serialization
by Daryle Walker 14 Aug '08

14 Aug '08

I was thinking about adding serialization to some times I've been working on in the sandbox. First I tried to recall how Mr. Ramey said serialization can be tested. I couldn't find the specific post I was thinking about, but others that were found gave me the answer. Reading other posts in that search prompted me to ask more questions. I could reduce the classes I'm working with to: //============================================= class computer; class context { public: typedef boost::array<uint_least32_t, 4> value_type; context(); // use auto copy-ctr, copy-=, dtr void operator ()( bool ); // consumer bool operator ==() const; // equals bool operator !=() const; // not-equals value_type operator ()() const; // producer private: friend class computer; boost::uint_fast64_t length; boost::array<uint_fast32_t, 4> buffer; boost::array<bool, 512> queue; template < class Archive > void serialize( Archive &ar, const unsigned int version ); }; class computer : public convenience_methods_base<context> { // An object of type "context" is incorporated in this object // due to the base class. A mutable/const pair of non-static // member functions named "context()" gives access to the inner // context object. public: typedef context::value_type value_type; // Put various access member functions here that forward to the // internals of the "context" type, which work because of the // friend declaration. private: template < class Archive > void serialize( Archive &ar, const unsigned int version ); }; //============================================= I initially planned to have serialization functions for these two classes, the "convenience_methods_base" base class template, plus two other class templates (a base class and a support class) that "convenience_methods_base" uses. But the e-mail search I mentioned found a thread from May 2007 (on the main Boost list) the suggested that the serialization of a non-primitive should match the user's external representation of the type, and not the type's particular internal structure. So I decided to keep the serialization protocol just for the two public-facing classes, "context" and "computer." I figured that the "computer" object can be serialized like: //============================================= template < class Archive > inline void computer::serialize( Archive &ar, const unsigned int version ) { ar & boost::serialization::make_nvp("context", this->context()); } //============================================= Which leaves how "context" objects are serialized. After thinking about it for hours, I decided to just whip out something quick & dirty and refine it later. So: //============================================= template < class Archive > inline void context::serialize( Archive &ar, const unsigned int version ) { ar & BOOST_SERIALIZATION_NVP( length ) & BOOST_SERIALIZATION_NVP( buffer ) & BOOST_SERIALIZATION_NVP( queue ); } //============================================= would give a final serialization, in my test file, of: //============================================= <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <test class_id="0" tracking_level="0" version="0"> <context class_id="1" tracking_level="0" version="0"> <length>1</length> <buffer class_id="2" tracking_level="0" version="0"> <elems> <count>4</count> <item>1732584193</item> <item>4023233417</item> <item>2562383102</item> <item>271733878</item> </elems> </buffer> <queue class_id="3" tracking_level="0" version="0"> <elems> <count>512</count> <item>1</item> <item>0</item>  <item>0</item> </elems> </queue> </context> </test> </boost_serialization> //============================================= Now I started refining, keeping the principle of not leaking implementation details in mind. The problem here is the array- counts, which I don't need since they'll never change. The first one I can fix by writing each element separately: //============================================= <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <test class_id="0" tracking_level="0" version="0"> <context class_id="1" tracking_level="0" version="0"> <length>1</length> <buffer-A>1732584193</buffer-A> <buffer-B>4023233417</buffer-B> <buffer-C>2562383102</buffer-C> <buffer-D>271733878</buffer-D> <message-tail class_id="2" tracking_level="0" version="0"> <elems> <count>512</count> <item>1</item> <item>0</item>  <item>0</item> </elems> </message-tail> </context> </test> </boost_serialization> //============================================= I've always wanted to use something like a base-64 string encoding of the bit array, because it's cool and it'd save space. I added conversion functions to/from the bit array and a std::string, and then (de)serialized the string. I also had to separate "serialize" into "save" and "load" since conversion is complementary, not identical. So now I have: //============================================= <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <test class_id="0" tracking_level="0" version="0"> <context class_id="1" tracking_level="0" version="0"> <length>1</length> <buffer-A>1732584193</buffer-A> <buffer-B>4023233417</buffer-B> <buffer-C>2562383102</buffer-C> <buffer-D>271733878</buffer-D> <message-tail>g</message-tail> </context> </test> </boost_serialization> //============================================= Then I added tests for: exactly 6 bits (i.e. one base-64 letter); a sextet (actually two) and a partial sextet together; filling a queue to capacity (actually one short of that since a full queue automatically activates a turnover); and going past capacity resulting in a new hash buffer and an empty message-tail. //============================================= <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <test class_id="0" tracking_level="0" version="0"> <context class_id="1" tracking_level="0" version="0"> <length>1</length> <buffer-A>1732584193</buffer-A> <buffer-B>4023233417</buffer-B> <buffer-C>2562383102</buffer-C> <buffer-D>271733878</buffer-D> <message-tail>g</message-tail> </context> </test> </boost_serialization> <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <test class_id="0" tracking_level="0" version="0"> <context class_id="1" tracking_level="0" version="0"> <length>6</length> <buffer-A>1732584193</buffer-A> <buffer-B>4023233417</buffer-B> <buffer-C>2562383102</buffer-C> <buffer-D>271733878</buffer-D> <message-tail>q</message-tail> </context> </test> </boost_serialization> <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <test class_id="0" tracking_level="0" version="0"> <context class_id="1" tracking_level="0" version="0"> <length>14</length> <buffer-A>1732584193</buffer-A> <buffer-B>4023233417</buffer-B> <buffer-C>2562383102</buffer-C> <buffer-D>271733878</buffer-D> <message-tail>qQg</message-tail> </context> </test> </boost_serialization> <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <test class_id="0" tracking_level="0" version="0"> <context class_id="1" tracking_level="0" version="0"> <length>511</length> <buffer-A>1732584193</buffer-A> <buffer-B>4023233417</buffer-B> <buffer-C>2562383102</buffer-C> <buffer-D>271733878</buffer-D> <message- tail>ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789- _AAAAAAAAAAH__________g</message-tail> </context> </test> </boost_serialization> <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <test class_id="0" tracking_level="0" version="0"> <context class_id="1" tracking_level="0" version="0"> <length>512</length> <buffer-A>2631642121</buffer-A> <buffer-B>80961853</buffer-B> <buffer-C>4033330630</buffer-C> <buffer-D>497373075</buffer-D> <message-tail></message-tail> </context> </test> </boost_serialization> //============================================= If you want to see the actual work, look at revision/change-set #48131 in Boost's Subversion set-up. Now to the actual questions: 1. If there's only one sub-object, base or member, that has any significant data, could someone call the "serialize" member function of that sub-object directly in the wrapping class's "serialize"? (This assumes that friendship is set up.) This would make the wrapping class look identical to the sub-object's class, right? Is this a good idea? 2. Before actually trying to serialize a string, I was worried that the string's serialization would include a length count. This would be unnecessary because the object's "length" attribute already implies the length of the string (int( ceil( double( length % 512 ) / 6.0 ) )). Here, we see that the string's length isn't explicitly included in the XML archive, so I have no worries. But what about non-XML archives? Will be string's length be directly serialized, wasting space? If so, how can I fix that? 3. Having to add std::string to support serialization makes my class header heavier. My class uses fixed-sized arrays, so is there any way that I can avoid allocating a string? For writing out, could I set up a char-array with the encoding and write that out? For reading in, can I read the string in piecemeal to a char-array just in case someone added more characters than required. My converter currently ignores illegal characters and stops when enough legal characters have been read. If what I ask is possible, would the reading routine have to seek to the end of the entry so further serialization isn't messed up? -- Daryle Walker Mac, Internet, and Video Game Junkie darylew AT hotmail DOT com

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just plain weirdness (serialization)
by Noah Roberts 14 Aug '08

14 Aug '08

I'm working with 1.33.1 here and can't upgrade at this point. I'm trying to compile something I compile with VS using mingw. I'm running into this weird problem. The code in question saves and loads a boost::array to an archive. In visual studio the project compiles. With mingw it does not and issues an error about boost::array<double, 4u> not having a serialize member function. So in an effort to try and trick down why it is working fine in visual studio I decided to make a minimal program that saves a boost::array to an archive. I get the same error... I'm trying to include every system file and boost header that would be included but I can't seem to make anything work. Has anyone any idea at all? I've been working on this for a few hours now and just cannot get a minimal program to compile, yet I've compiled the original project many times in VS...including several times today. At a loss here...

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