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Re: [Boost-users] Stepping into a boost::function while debugging
by Peter Åberg 12 May '09

12 May '09

Ok, works alright I guess :-) /PÅ > Peter ?berg wrote: > > > Does anyone have a tip, suggestions or workaround on how one should do > > to step into the target function of a boost::function while debugging > > in VS 2008 (VC9), without wading through the boost::function > > implementation? > > > > I have looked around a bit now and have not found any solution except > > putting a breakpiont in the target function which may not be practical > > when one does not know which function it is. > > > > I get the feeling one have to wait for MS to add a feature like "step > > through code I don't want to see". But until then, what do you folks do? > > > > Designing with delegates in C++ feels a bit like a show-stopper for me > > until I can step into a delegate target function without getting lost > > in a haystack. > > Steven Watanabe wrote: > > I just hit step into until I get to familiar code. There isn't actually > a lot of code > to step through when calling a Boost.Function. > > In Christ, > Steven Watanabe

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Next layer: Boost.Asio mixins?
by Boris Schaeling 11 May '09

11 May '09

Did anyone create and use Boost.Asio mixins and can share his experience? I especially wonder if there is a benefit or if it's just an exercise in templates. The reason I started to think about Boost.Asio mixins is that I see the very same code in various classes which all use Boost.Asio objects. I would assume that this is not only true in my projects but also in others. Here's an example. Let's say we create a client class to connect to another host. We could come up with something like this: class client { public: void resolve(std::string host, std::string service); void connect(boost::asio::ip::tcp::resolver::iterator endpoint_iterator); void send(std::string msg); void receive(); private: boost::asio::ip::tcp::resolver r; boost::asio::ip::tcp::socket s; }; If we create another class to encapsulate a POSIX file descriptor we don't need resolve() and connect() but send() and receive(): class posix_fd { public: void send(std::string msg); void receive(); private: boost::asio::posix::stream_descriptor fd; }; While the two classes are based on different I/O objects the implementation of send() and receive() could be the same. That lead me to create mixins with which I can define client and posix_fd like this: class client : public resolver<boost::asio::ip::tcp::resolver, handler>, public connector<boost::asio::ip::tcp::socket, handler>, public sender<boost::asio::ip::tcp::socket, handler>, public receiver<boost::asio::ip::tcp::socket, handler> { // Inherited from parent classes: // void resolve(std::string host, std::string service); // void connect(boost::asio::ip::tcp::resolver::iterator endpoint_iterator); // void send(std::string msg); // void receive(); }; class posix_fd : public sender<boost::asio::posix::stream_descriptor, handler>, public receiver<boost::asio::posix::stream_descriptor, handler> { // Inherited from parent classes: // void send(std::string msg); // void receive(); }; Sending and receiving data asynchronously has been implemented now once and for all in the sender and receiver template classes. As the implementation doesn't differ for Boost.Asio I/O objects they can be reused. And if we had concepts already in C++ the mixins could be based on them. It all seems to fit nicely together. While there are some problems, too, I haven't made my mind yet if these Boost.Asio mixins are an improvement or make code more complicated. I'm not asking about mixins in general but wonder if anyone had a good or bad experience using them with Boost.Asio? Or are all Boost.Asio users simply calling the very same async_write() and async_read() functions again and again, creating yet another buffer, checking again the error code in the handlers etc.? Boris

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Re: [Boost-users] iterators must go
by John Dlugosz 11 May '09

11 May '09

> Date: Sun, 10 May 2009 09:24:42 -0400 > From: Neal Becker <ndbecker2(a)gmail.com> > Subject: [Boost-users] iterators must go > To: boost-users(a)lists.boost.org > Message-ID: <gu6kiq$2km$1(a)ger.gmane.org> > Content-Type: text/plain; charset="US-ASCII" > > Interesting presentation: > > http://www.boostcon.com/site- > media/var/sphene/sphwiki/attachment/2009/05/08/iterators-must-go.pdf > ******************************************** Re slide #21, he didn't mention the biggest one. I had a rather negative reaction to the design when I first saw the proposal and design that was to become the STL. The two iterators of a range have no connection to each other, and it is easy to get them mixed up with no way to test that the second is in the same collection as the first. Rather than (begin,end), I much prefer (begin, length) as a specification. And in implementation, iterators are literally as bad as pointers. I've preached that they must be treated like pointers, hidden away behind walls of encapsulation. When I first saw Boost ranges, I thought that was indeed much better. Way back when, abstracting a "range" and still allowing more generality was way beyond the ability of templates or template programmers. Slide #26: Yes! That discussion should have been had way back when. But the fait accompli of an existing library to serve as a starting point, and politics, shut down any hint of backtalk. Slide #47: shades of Perl 6...makes me think how the previous few slides of operations on ranges is like Perl. (#48) But in Perl6, even "Int" types can hold exceptional values, so list.size() would have no trouble returning Inf. --John (sorry about the footer; it's not my idea) TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

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Re: [Boost-users] [regex] problem with linking to boost_regex
by Phani Deepak Parasuramuni 11 May '09

11 May '09

>n addition , I believe that the correct option is >-lboost_regex-gcc43-mt, since gcc will add the >lib prefix automatically. Thanks, This solved the problem. >In Christ, >Steven Watanabe

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Re: [Boost-users] boost::asio and boost::statecharts newbie
by Marat Abrarov 11 May '09

11 May '09

Dear, Dave It's very interesting to see ASIO and FSM integration (I'd always been confused how to use them together). I haven't seen your code, but you can see mine: https://sourceforge.net/projects/asio-samples/. It's without FSM but with serial port too (Windows, may be Linux/Unix). The main concept is async active object(s) (techniques of their creation and usage on the top of ASIO) with external (user) async operations and internal ones (internal loops of async operatins). Also I tried to heavily use custom memory allocation (to reduce memory allocator calls which slows down multithreaded environment). The code isn't clean enough but it works fine. Best regards, Marat

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[1.38.0] date_time compile error on Solaris 10 Sun Studio 11
by mojo_risin 11 May '09

11 May '09

Hi, The following code: date now(day_clock<date>::local_day()); produces this error: "Error: No parameters provided for template." Any idea? Thanks in advance, Paulo -- View this message in context: http://www.nabble.com/-1.38.0--date_time-compile-error-on-Solaris-10-Sun-St… Sent from the Boost - Users mailing list archive at Nabble.com.

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Easy Build and Install
by Rodolfo Federico Gamarra 11 May '09

11 May '09

Hi all, I've downloaded boost_1_39_0.tar.gz and proceeded as told in http://www.boost.org/doc/libs/1_39_0/more/getting_started/unix-variants.html When the last step (./bjam install) was finished, I didn't find a "lib" directory within my prefix path (as told in that page and by ./bootstrap.sh --help). After looking for a while I found the libraries in "/lib". Taking a look at the bootstrap.sh file I noticed # Setup paths if test "x$EPREFIX" = x; then EPREFIX="$PREFIX" fi if test "x$LIBDIR" = x; then LIBDIR="$EXPREFIX/lib" fi Note that for building "LIBDIR" "EXPREFIX" is used instead of "EPREFIX", the former one does not appear anymore in the file. It seems that there was a typo. Thanks a lot. -- Rodolfo Federico Gamarra

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(De-) Serialization with constructor arguments
by Damien Hocking 11 May '09

11 May '09

Hi all, I'm using boost::serialization in a project and I was wondering if there's a way to deserialize through a non-default constructor that takes an argument. All the examples I've seen use default constructors. Damien

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Boost ASIO build info (Topic 3)
by Dave Mazzoni 10 May '09

10 May '09

> 3. building asio tutorial examples (Paul Sutcliffe) > ---------- Forwarded message ---------- > From: Paul Sutcliffe <psutclif(a)it.uts.edu.au> > To: boost-users(a)lists.boost.org > Date: Sun, 10 May 2009 22:17:17 +1000 > Subject: [Boost-users] building asio tutorial examples > I'm trying to build the asio tutorial code > http://www.boost.org/doc/libs/1_38_0/doc/html/boost_asio/tutorial.html > > Is there a make file anywhere or perhaps a command line example showing > exactly what libs are needed? > thanks Here's a Makefile that I use for building a project with boost::asio libs > BOOST_INCLUDE=/usr/local/include/boost-1_39 > BOOST_LIB=/usr/local/lib/boost-1_39 > LIBS=/usr/local/lib/libboost_system-gcc42-mt-1_39.so.1.39.0 > CC=/usr/bin/g++ #Path to your g++ compler: type *'which g++*' to find out > > all: serial_test > > serial_test: main.o serial_asio.hpp serial_asio.o > $(CC) -I $(BOOST_INCLUDE) -L $(LIBS) main.cpp \ > serial_asio.o -lboost_system-gcc40-mt -t -o serial_test > > main.o: main.cpp > $(CC) -I $(BOOST_INCLUDE) -c main.cpp -o main.o > > serial_asio.o: serial_asio.cpp > $(CC) -I $(BOOST_INCLUDE) -c serial_asio.cpp -o serial_asio.o > > > clean: > rm -f *.o serial_test > > And here's what's in my *serial_asio.hpp:* #ifndef SERIAL_ASIO_HPP #define SERIAL_ASIO_HPP #include <boost/asio.hpp> #include <boost/enable_shared_from_this.hpp> #include <boost/shared_ptr.hpp> #include <boost/bind.hpp> #include <boost/asio.hpp> #include <boost/asio/serial_port.hpp> #include <string> #include <iostream> #include <sstream> using namespace boost; using namespace std; enum { Max_read_length = 256 }; class Serial_connection { public: Serial_connection( boost::asio::io_service& io_service ); ~Serial_connection(); typedef boost::shared_ptr<Serial_connection> pointer; static pointer create ( boost::asio::io_service& io_service ); void read_start(); private: void handle_write ( const boost::system::error_code& an_error, size_t bytes_transferred ); void handle_read ( const boost::system::error_code& an_error, size_t bytes_transferred ); boost::asio::serial_port serial_port_; boost::asio::io_service& io_service_; char read_msg_[Max_read_length]; boost::asio::streambuf stream_buffer_; char delimiter_; stringstream ss_; bool flip_flop; }; #endif If you need more information, I'd be glad to post it here. I think this answers your question regarding "builds". Regards, Dave > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

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[wave] How to enumerate all function declarations in a preprocessed header
by David Larsson 10 May '09

10 May '09

Hi! I'm trying to use booost.wave to parse some C headers and generate code for each function declaration found. How would you write code that identifies all function declarations? Is there any higher level structure that helps me finding this or do I need to create some state machine that matches the pattern for a function declaration from what's found in the token iterator? Thanks /David

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[Proto] Questions about deep_copy
by Kim Kuen Tang 10 May '09

10 May '09

Hi all, consider the following code: std::vector<double> a(10,1.0), b(10,2.0); BOOST_AUTO( temp , proto::as_expr<MixedDomain>(a+b+0.1) ); // is the function proto::as_expr<MixedDomain>() needed? temp[0]; Here the expression a +b+ 0.1 is created by the MixedDomain as it is from the mixed example. And the operator[] is definde by: typedef typename boost::remove_reference< typename boost::result_of<Begin(MixedExpr<Expr> const & )>::type>::type Expr2; typedef typename proto::result_of::eval<Expr2, DereferenceCtx const>::type result_type; result_type operator[](std::size_t index) const { Expr2 expr2 = Begin()(*this); DereferenceCtx const deref = {}; return proto::eval(expr2, deref); } But the code crashes during runtime. The reason is that the number 0.1 is held by reference. So the number 0.1 goes out of scope before i try to evaluate the expression temp[0]; A way to solve this problem is to deep copy the expression with deep_copy. But on the other hand i do not want to copy the two vectors a and b. So i am asking what is the best way to solve this problem? Can this problem be solved by defining a Grammar that copies the number 0.1? Or do i need to extend the deep_copy by deep_copy_if<double>() (a+b+0.1). It should copy the terminal only if it matches the specified type. Thanks for your help. B/Rgds Kim Here is the whole code: //[ Mixed /////////////////////////////////////////////////////////////////////////////// // Copyright 2008 Eric Niebler. 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) // // This is an example of using BOOST_PROTO_DEFINE_OPERATORS to Protofy // expressions using std::vector<> and std::list, non-proto types. It is a port // of the Mixed example from PETE. // (http://www.codesourcery.com/pooma/download.html) #include <list> #include <cmath> #include <vector> #include <complex> #include <iostream> #include <stdexcept> #include <boost/proto/core.hpp> #include <boost/proto/debug.hpp> #include <boost/proto/context.hpp> #include <boost/proto/transform.hpp> #include <boost/proto/proto_typeof.hpp> #include <boost/proto/deep_copy.hpp> #include <boost/utility/enable_if.hpp> #include <boost/typeof/std/list.hpp> #include <boost/typeof/std/vector.hpp> #include <boost/typeof/std/complex.hpp> #include <boost/type_traits/remove_reference.hpp> #include <boost/utility/result_of.hpp> #include <boost/typeof/typeof.hpp> namespace proto = boost::proto; namespace mpl = boost::mpl; using proto::_; template<typename Expr> struct MixedExpr; template<typename Iter> struct iterator_wrapper { typedef Iter iterator; iterator_wrapper(Iter it) :it(it) {}; Iter it; }; struct begin_iter :proto::callable { template<class Sig> struct result; template<class This, class Cont> struct result<This(Cont)> : proto::result_of::as_expr< iterator_wrapper<typename boost::remove_reference<Cont>::type::const_iterator> > {}; template<class Cont> typename result<begin_iter(Cont const&)>::type operator()(Cont const& cont) const { iterator_wrapper<typename Cont::const_iterator> it(cont.begin()); return proto::as_expr(it); } }; template<typename Num> struct num_wrapper { typedef Num numeric; num_wrapper(Num num) :num_(num) { //BOOST_MPL_ASSERT( (boost::is_reference<Num>) ); }; Num num_; }; struct begin_num :proto::callable { template<class Sig> struct result; template<class This, class Cont> struct result<This(Cont)> : proto::result_of::make_expr<proto::tag::terminal ,num_wrapper< typename boost::remove_const< typename boost::remove_reference<Cont>::type >::type > > {}; template<class Cont> typename result<begin_num(Cont const)>::type operator()(Cont const cont) const { //BOOST_MPL_ASSERT( (boost::is_reference<result<begin_num(Cont const&)>::type>) ); num_wrapper<Cont> num(cont); return proto::make_expr<proto::tag::terminal>(num); } }; // Here is a grammar that replaces vector and list terminals with their // begin iterators struct Begin : proto::or_< proto::when< proto::terminal<std::vector<_,_> >, begin_iter(proto::_value)> ,proto::when< proto::terminal<std::list<_,_> >, begin_iter(proto::_value)> ,proto::when<proto::terminal<double>, begin_num(proto::_value) > ,proto::when<proto::terminal<_> > ,proto::nary_expr<_ , proto::vararg<Begin> > > {}; struct DereferenceCtx { template<typename Expr,typename EnableIf=void> struct eval : proto::default_eval<Expr, DereferenceCtx const> {}; template<typename Expr> struct eval<Expr, typename boost::enable_if< proto::matches<Expr, proto::terminal< iterator_wrapper<_> > > >::type > { typedef typename proto::result_of::value<Expr>::type IteratorWrapper; typedef typename IteratorWrapper::iterator iterator; typedef typename std::iterator_traits<iterator>::reference result_type; template<typename Expr> result_type operator()(Expr &expr,DereferenceCtx const&) { return *proto::value(expr).it; } }; template<typename Expr> struct eval<Expr, typename boost::enable_if< proto::matches<Expr, proto::terminal< num_wrapper<_> > > >::type > { typedef typename proto::result_of::value<Expr>::type NumWrapper; typedef typename NumWrapper::numeric result_type; template<typename Expr> result_type operator()(Expr &expr,DereferenceCtx const&) { return proto::value(expr).num_; } }; }; struct IncrementCtx { template<typename Expr,typename EnableIf=void> struct eval : proto::null_eval<Expr, IncrementCtx const> {}; template<typename Expr> struct eval<Expr, typename boost::enable_if< proto::matches<Expr, proto::terminal<iterator_wrapper<_> > > >::type> { typedef void result_type; template<typename Expr> result_type operator()(Expr& expr, IncrementCtx const & ) { ++proto::value(expr).it; } }; }; struct AdvanceCtx { std::size_t index_; template<typename Expr,typename EnableIf=void> struct eval : proto::null_eval<Expr, AdvanceCtx const> {}; template<typename Expr> struct eval<Expr, typename boost::enable_if< proto::matches<Expr, proto::terminal<iterator_wrapper<_> > > >::type> { typedef void result_type; template<typename Expr> result_type operator()(Expr& expr, AdvanceCtx const & ctx) { std::advance(proto::value(expr).it, ctx.index_); } }; }; // A grammar which matches all the assignment operators, // so we can easily disable them. struct AssignOps : proto::switch_<struct AssignOpsCases> {}; // Here are the cases used by the switch_ above. struct AssignOpsCases { template<typename Tag, int D = 0> struct case_ : proto::not_<_> {}; template<int D> struct case_< proto::tag::plus_assign, D > : _ {}; template<int D> struct case_< proto::tag::minus_assign, D > : _ {}; template<int D> struct case_< proto::tag::multiplies_assign, D > : _ {}; template<int D> struct case_< proto::tag::divides_assign, D > : _ {}; template<int D> struct case_< proto::tag::modulus_assign, D > : _ {}; template<int D> struct case_< proto::tag::shift_left_assign, D > : _ {}; template<int D> struct case_< proto::tag::shift_right_assign, D > : _ {}; template<int D> struct case_< proto::tag::bitwise_and_assign, D > : _ {}; template<int D> struct case_< proto::tag::bitwise_or_assign, D > : _ {}; template<int D> struct case_< proto::tag::bitwise_xor_assign, D > : _ {}; }; // A vector grammar is a terminal or some op that is not an // assignment op. (Assignment will be handled specially.) struct MixedGrammar : proto::or_< proto::when< proto::terminal<double const&> , begin_num(proto::_value)> , proto::terminal<_> , proto::and_< proto::nary_expr<_, proto::vararg<MixedGrammar> > , proto::not_<AssignOps> > > {}; // Expressions in the vector domain will be wrapped in VectorExpr<> // and must conform to the VectorGrammar struct MixedDomain : proto::domain<proto::generator<MixedExpr>, MixedGrammar> {}; // Here is MixedExpr, a wrapper for expression types in the MixedDomain. template<typename Expr> struct MixedExpr : proto::extends<Expr, MixedExpr<Expr>, MixedDomain> { explicit MixedExpr(Expr const &expr) : proto::extends<Expr, MixedExpr<Expr>, MixedDomain>(expr) {} typedef typename boost::remove_reference< typename boost::result_of<Begin(MixedExpr<Expr> const & )>::type>::type Expr2; typedef typename proto::result_of::eval<Expr2, DereferenceCtx const>::type result_type; result_type operator[](std::size_t index) const { //BOOST_MPL_ASSERT( (boost::is_reference<Expr2>) ); Expr2 expr2 = Begin()(*this); AdvanceCtx const adv = {index}; proto::eval(expr2, adv); DereferenceCtx const deref = {}; return proto::eval(expr2, deref); } private: // hide this: //using proto::extends<Expr, MixedExpr<Expr>, MixedDomain>::operator []; }; // Define a trait type for detecting vector and list terminals, to // be used by the BOOST_PROTO_DEFINE_OPERATORS macro below. template<typename T> struct IsMixed : mpl::false_ {}; template<typename T, typename A> struct IsMixed<std::list<T, A> > : mpl::true_ {}; template<typename T, typename A> struct IsMixed<std::vector<T, A> > : mpl::true_ {}; namespace MixedOps { // This defines all the overloads to make expressions involving // std::vector to build expression templates. BOOST_PROTO_DEFINE_OPERATORS(IsMixed, MixedDomain) struct assign_op { template<typename T, typename U> void operator ()(T &t, U const &u) const { t = u; } }; struct plus_assign_op { template<typename T, typename U> void operator ()(T &t, U const &u) const { t += u; } }; struct minus_assign_op { template<typename T, typename U> void operator ()(T &t, U const &u) const { t -= u; } }; struct sin_ { template<typename Sig> struct result; template<typename This, typename Arg> struct result<This(Arg)> : boost::remove_const<typename boost::remove_reference<Arg>::type> {}; template<typename Arg> Arg operator ()(Arg const &a) const { return std::sin(a); } }; template<typename A> typename proto::result_of::make_expr< proto::tag::function , MixedDomain , sin_ const , A const & >::type sin(A const &a) { return proto::make_expr<proto::tag::function, MixedDomain>(sin_(), boost::ref(a)); } template<typename FwdIter, typename Expr, typename Op> void evaluate(FwdIter begin, FwdIter end, Expr const &expr, Op op) { IncrementCtx const inc = {}; DereferenceCtx const deref = {}; typename boost::result_of<Begin(Expr const &)>::type expr2 = Begin()(expr); for(; begin != end; ++begin) { op(*begin, proto::eval(expr2, deref)); proto::eval(expr2, inc); } } template<typename Vector, typename Expr> Vector& assign(Vector &arr,Expr const &expr) { evaluate(arr.begin(),arr.end(),proto::as_expr<MixedDomain>(expr),assign_op()); return arr; } // Add-assign to a vector from some expression. template<typename T, typename A, typename Expr> std::vector<T, A> &operator +=(std::vector<T, A> &arr, Expr const &expr) { evaluate(arr.begin(), arr.end(), proto::as_expr<MixedDomain>(expr), plus_assign_op()); return arr; } // Add-assign to a list from some expression. template<typename T, typename A, typename Expr> std::list<T, A> &operator +=(std::list<T, A> &arr, Expr const &expr) { evaluate(arr.begin(), arr.end(), proto::as_expr<MixedDomain>(expr), plus_assign_op()); return arr; } // Minus-assign to a vector from some expression. template<typename T, typename A, typename Expr> std::vector<T, A> &operator -=(std::vector<T, A> &arr, Expr const &expr) { evaluate(arr.begin(), arr.end(), proto::as_expr<MixedDomain>(expr), minus_assign_op()); return arr; } // Minus-assign to a list from some expression. template<typename T, typename A, typename Expr> std::list<T, A> &operator -=(std::list<T, A> &arr, Expr const &expr) { evaluate(arr.begin(), arr.end(), proto::as_expr<MixedDomain>(expr), minus_assign_op()); return arr; } } int main() { using namespace MixedOps; int n = 10; std::vector<int> a,b,c,d; std::list<double> e; std::list<std::complex<double> > f; int i; for(i = 0;i < n; ++i) { a.push_back(i); b.push_back(2*i); c.push_back(3*i); d.push_back(i); e.push_back(0.0); f.push_back(std::complex<double>(1.0, 1.0)); } BOOST_AUTO(temp ,c + a + 0.1 ); for(int i=0, end=n;i<end;++i) std::cout<<temp[i]<<"\t"; //f -= sin(0.1 * e * std::complex<double>(0.2, 1.2)); //std::list<double>::const_iterator ei = e.begin(); //std::list<std::complex<double> >::const_iterator fi = f.begin(); //for (i = 0; i < n; ++i) //{ // std::cout // << "a(" << i << ") = " << a[i] // << "b(" << i << ") = " << b[i] // << "c(" << i << ") = " << c[i] // << "d(" << i << ") = " << d[i] // << "e(" << i << ") = " << *ei++ // << "f(" << i << ") = " << *fi++ // << std::endl; //} //boost::array<double,10> sad; } //]

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[regex] problem with linking to boost_regex
by Phani Deepak Parasuramuni 10 May '09

10 May '09

hi, this is the first time iam using boost::regex. when i compile the program, it lists a lot of 'undefined reference to' s to regex functions. tried setting linked flag -llibboost_regex-gcc43-mt and -L/usr/local/lib in eclipse but no use. please help. - Phani.

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building asio tutorial examples
by Paul Sutcliffe 10 May '09

10 May '09

I'm trying to build the asio tutorial code http://www.boost.org/doc/libs/1_38_0/doc/html/boost_asio/tutorial.html Is there a make file anywhere or perhaps a command line example showing exactly what libs are needed? thanks

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boost 1.38 test suite in separate files
by Nu Ai Tang 10 May '09

10 May '09

In the documentation from boost 1.38 (in the Unit Test Framework), there is this example if having multiple test suits. (Example follows..) My question is how can this be broken up and placed into different files? For example, the files could be testSuite1.cpp, testSuite2.cpp, and runTheseTestSuite.cpp. #define BOOST_TEST_MODULE example #include <boost/test/included/unit_test.hpp> BOOST_AUTO_TEST_SUITE( test_suite1 ) BOOST_AUTO_TEST_CASE( test_case1 ) { BOOST_WARN( sizeof(int) < 4 ); } BOOST_AUTO_TEST_CASE( test_case2 ) { BOOST_REQUIRE_EQUAL( 1, 2 ); BOOST_FAIL( "Should never reach this line" ); } BOOST_AUTO_TEST_SUITE_END() BOOST_AUTO_TEST_SUITE( test_suite2 ) BOOST_AUTO_TEST_CASE( test_case3 ) { BOOST_CHECK( true ); } BOOST_AUTO_TEST_CASE( test_case4 ) { BOOST_CHECK( false ); } BOOST_AUTO_TEST_SUITE_END()

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[uBLAS] Initialize a matrix by T*?
by Marco Guazzone 10 May '09

10 May '09

Hi, I'm new to uBLAS. I wonder if there is an efficient way to initialize a ublas::matrix<T> by a T*. Somthing like a copy(matrix<T>& m, T* p, size_t nrows, size_t ncols). For instance: --- [code_snip] --- double* pd = new double[10*20]; //... ublas::matrix<double> m; copy(m, pd, 10, 20); --- [/code_snip] --- Obviously I can create a 10x20 empty matrix (matrix<T> m(10,20)) and then scan the T* assigning each element one at time. But is there a more efficient way? Thank you very much in advance!! -- Marco

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boost::asio and boost::statecharts newbie question
by Dave Mazzoni 10 May '09

10 May '09

Hello all - I am using the boost::asio library to do serial I/O with simple Linux serial port(s) like /dev/ttyS0. I have found out how this works, and it is a very impressive library (I will offer a small example program so that you might include it for other users of ASIO serial ports once I've got it cleaned up). However, in addition to using boost::asio, I am using the boost::statechart library as the controller (FSM) for a project. I have managed to get the serial port working with the boost::asio library. Now, my problem is that I have an io_service defined and initialized in my statechart FSM. Is there some way to cast or otherwise use the io_service that I have therein into a serial_port? In other words, I would rather not have to put the serial port handling code in the FSM (I'd rather 'refer' to it using the io_service if it is possible). Thanks for your help! Dave

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boost::thread build with 64-bit mingw gcc
by Serge Skorokhodov 09 May '09

09 May '09

Hi, I tried to build boost 1.39 with 64-bit gcc 4.4 from www.equation.com and the thread library failed to compile. As it is stated here (http://sourceforge.net/forum/message.php?msg_id=5570690) the problem is (partly at least) lack of boost::thread support for 64-bit windows gcc. Will coming 1.40 version address this problem? TIA -- The fish that is singing in Ucayali river...

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mpl::find_if / placeholder question
by vasyl_y 09 May '09

09 May '09

Hi, I started learn mpl and here we go... I have an mpl::vector of compund types and i want to find an element in vector based on property of compound type and cannot find the way to do it, any suggestions? Here is an example how i'm trying to do it: #include <boost/mpl/vector.hpp> #include <boost/mpl/find_if.hpp> #include <boost/type_traits.hpp> namespace mpl = boost::mpl; template<typename T, int id> struct Type2IdLink { typedef T value_type; typedef mpl::int_<id> type_id; }; typedef Type2IdLink<char, 1> v1; typedef Type2IdLink<int, 2> v2; typedef Type2IdLink<unsigned, 3> v3; typedef mpl::vector<v1, v2, v3> types; // This work typedef mpl::find_if<types, boost::is_same<mpl::_1, v2> >::type iter; // This does not work: // value_type is not a member of mpl_::_1 typedef mpl::find_if<types, boost::is_same<mpl::_1::value_type, v2> >::type iter; BOOST_MPL_ASSERT_RELATION( iter::pos::value, == , 1); Using BOOST version 1.38, GCC4.3. Thank You -- View this message in context: http://www.nabble.com/mpl%3A%3Afind_if---placeholder-question-tp23463044p23… Sent from the Boost - Users mailing list archive at Nabble.com.

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boost - asio - advise
by Tim Pynegar 09 May '09

09 May '09

Hi, I'm trying to use asio for a udp client / server arrangment. I started by calling run on the io_service object on a separate thread and the using the async_read_from and the async_send_to. I was calling these from the main application thread. I was getting a lot of these errors that was causing an exception on the io_service run method. First-chance exception at 0x7c812afb in Testbed.exe: Microsoft C++ exception: boost::system::system_error at memory location 0x0012e29c. An invalid argument was supplied This happens after calling the async_send_to method. I've added in a send buffer and started to poll the io_service object instead of running it on it's own thread which has cut down the freqency this is happening however on occations it still does and i'd like to have it running on it's own thread. The question is really should i put in a mutex lock in my sendto function that call's the async_send_to that is unlocked when i recieve the handlesentto callback that's called when the async_send_to is finished. If i do this doesn't this basically make it a blocking function call in the same way as if i call the regular send_to function. There are other options i've thought of but they all seem to result in it basically becoming blocking. I've looked through the examples and there is a lot of different potential choices to make and was looking to see if anyone could advise on an arrangement that would allow for using multiple threads but block as little as possible. Thanks, Tim.

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Asio in Windows/Linux
by Kenny Stone 09 May '09

09 May '09

I'm trying to use asio in linux and windows, and I have to use a very specific way of starting my IO Service to get it to work in windows xp: void start() { tcp::endpoint endpoint = *iterator_; socket_.async_connect(endpoint, boost::bind(&MessageHandler::handle_connect, this, boost::asio::placeholders::error, ++iterator_ ) ); boost::thread t( boost::bind( &boost::asio::io_service::run, &(socket_.get_io_service() ))); t.detach(); //threadPool_.schedule(boost::bind( &boost::asio::io_service::run, &(socket_.get_io_service()) ) ); } The commented out line is what I wanted to use (threadpool), as thread detach is far from an ideal situation. To work in windows, I have to call io_service.run() in this function and thread detach; it doesn't seem to work any other way. Everything pretty much works in linux. Is there a pattern that I should be using here for cross platform usage of the library? Any ideas why the threadpool solution doesn't work in windows? ( http://threadpool.sourceforge.net/) Thanks, -- Kenny Stone Connamara Systems, LLC

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[BGL] Auto Connect vertexes by predicate?
by arm2arm 09 May '09

09 May '09

Hello, Are there ways to generate Graph with edges by the user defined function? Should I generate Vertex relations by hand then put it in to Graph? I would like to feed graph by points 3d and each point is linked to its closest neighbor by distance. Then as a next step I would like to dig in the graph the sub-graphs with the given linking length. My Data structure is following: _____________________ class CCoord { public: CCoord(){}; CCoord(int id_,MyFloat x_,MyFloat y_,MyFloat z_, MyFloat w_=0): id(id_), x(x_), y(y_), z(z_), w(w_){ if(w==0.0) w=sqrt(x*x+y*y+z*z); }; MyFloat x, y, z; int id; MyFloat w; } typedef std::vector<CCoord> typeVecData; typedef adjacency_list < vecS, vecS, undirectedS, no_property, property < edge_weight_t, MyFloat > > Graph; typedef graph_traits < Graph >::edge_descriptor Edge; typedef graph_traits < Graph >::vertex_descriptor Vertex; typedef std::pair<int, int> E; typeVecData data(num_nodes); srand(0); generate(data.begin(),data.end(),gencoord); typedef std::pair<int, int> Edge; Graph G(5); add_edge(0, 2, G);//how to apply relation function? ________________________________________________ What is the correst way to implement this algorithm using BGL? Thank you beforehand. Arman -- View this message in context: http://www.nabble.com/-BGL--Auto-Connect-vertexes-by-predicate--tp23451992p… Sent from the Boost - Users mailing list archive at Nabble.com.

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Re: [Boost-users] [asio] sync receive_from with timeout
by Michael Dehmlow 09 May '09

09 May '09

Ha this is exactly the problem I ran into not two days ago I agree it would be nice if there was a timeout for the library: I used to following: //Oh throw a sleep in there: while(!timeout.elapsed()) { boost::system::error_code ec; boost::asio::socket_base::non_blocking_io command(true); socket.io_control(command); bytesRead = _socket->read_some(boost::asio::buffer(data, dataBufferSize), ec); if(error&&boost::asio::error::would_block!=error) { //there is some other error the client has disconnected; } else { //I must have got some data or theres no data yet check bytesRead for that } boost::this_thread::sleep( boost::posix_time::milliseconds(100)); } No extra threads necessary. Stephan Menzel-3 wrote: > > Is the subject Jehova enough for you? ;-) > > Great. > > Well, I haven't raised the subject so far but I'd certainly like to do so > now. For years now I am not only a user but also an admirer of boost asio. > Something that has always puzzled me however is, why a timeout > functionality which is something very common and essential for sync IO > just doesn't seem to be there. > > I think there are cases where syncronous IO is a better way to go and no > async approach is sensible. In my case this is a collection of static > functions that do UDP communication and therefore have to be sync because > I just want them to be able to return and throw exceptions and be able to > be called from anyone at any time. > > As always when I stumble across the asio/timeout problem I start googling > around. When people raise the topic here they are usually pointed to an > answer Chris Kohlhoff gave to someone asking that: > > http://lists.boost.org/Archives/boost/2007/04/120339.php > > ... which is good for tcp and works alright even though in my opinion it > leaves the question why it has to be so compilicated to do something so > basic. IMHO sync IO is all but pointless without a timeout. > > Anyway, I started to turn this into a UDP version and ended up with > something very similar: > > inline void set_result(boost::optional<boost::system::error_code>* a, > boost::system::error_code b) { > a->reset(b); > }; > > template <typename MutableBufferSequence> > void udp_read_with_timeout(boost::asio::ip::udp::socket& sock, int tmo, > boost::asio::ip::udp::endpoint &endpoint, const MutableBufferSequence& > buffers) { > > boost::optional<boost::system::error_code> timer_result; > boost::asio::deadline_timer timer(sock.io_service()); > timer.expires_from_now(boost::posix_time::seconds(tmo)); > timer.async_wait(boost::bind(set_result, &timer_result, _1)); > > boost::optional<boost::system::error_code> read_result; > sock.async_receive_from(buffers, endpoint, boost::bind(set_result, > &read_result, _1)); > > sock.io_service().reset(); > while (sock.io_service().run_one()) { > if (read_result) > timer.cancel(); > else if (timer_result) > sock.cancel(); > } > > if (*read_result) > throw boost::system::system_error(*read_result); > }; > > > So now I started to go ahead with that but I had to notice two things. > First, the performance impact is massive to a point that forces me to > reconsider. Second, when I use that in a multithreaded environment the > whole thing seems to block in some threads randomly. I have made test > program where I have multiple threads using that method, just sending an > UDP request to a server and waiting for an answer using this function. In > one thread everything is slow but continously running. In more than one > thread it blocks for up to 5 or 6 seconds every few (10-20) runs for no > visible reason. In my scenario all those threads share a socket protected > by a mutex so if one of them blocks all will be halted. > > So I come to think this is not a good way to handle the problem. Does > anyone have some thoughts on that? May this be a bug in asio (1.38) or > perhaps in my function? Or is there a better way to do sync UDP IO with a > timeout functionality? > > Cheers... > > Stephan > > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > -- View this message in context: http://www.nabble.com/-asio--sync-receive_from-with-timeout-tp22326399p2233… Sent from the Boost - Users mailing list archive at Nabble.com.

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is this possible with tuples in c++0x ?
by Germán Diago 09 May '09

09 May '09

template <typename... Types> class tuple ... { template <typename N> auto operator[](std::size_t n = N) -> constexpr decltype(get<N>(*this)) { return get<N>(*this); } }; If this is possible, you could do (and it would be way more natural than get<3>(t)): tuple<int, float, float, string, mytype> t; t[3] = "hello"; But I feel this is not legal because of parameter std::size_t :(.

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more than one template with automated registration
by tang10＠llnl.gov 08 May '09

08 May '09

Is there a macro similar to BOOST_AUTO_TEST_CASE_TEMPLATE for this: template< typename Value, typename Field > void testFunction() { ... }; Thanks, Nu Ai.

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boost.python error while ./bjam install
by Aamir Ahmed Khan 08 May '09

08 May '09

I am compiling boost.python libraries by following the procedure given at http://www.boost.org/doc/libs/1_39_0/more/getting_started/unix-variants.htm… I first configure the build and installation using bootstrap.sh script $ ./bootstrap.sh --with-python=/usr/bin/python2.5 --with-libraries=python --prefix=~/work/boost/setup/boost_1_39_0/mybuild Here are the contents of project-config.jam fie as generated by the script. # Boost.Build Configuration > # Automatically generated by bootstrap.sh > > import option ; > import feature ; > > # Compiler configuration. This definition will be used unless > # you already have defined some toolsets in your user-config.jam > # file. > if ! gcc in [ feature.values <toolset> ] > { > using gcc ; > } > > project : default-build <toolset>gcc ; > > # Python configuration > using python : 2.5 : /usr ; > > # List of --with-<library> and --without-<library> > # options. If left empty, all libraries will be built. > # Options specified on the command line completely > # override this variable. > libraries = --with-python ; > > # These settings are equivivalent to corresponding command-line > # options. > option.set prefix : ~/work/boost/setup/boost_1_39_0/mybuild ; > option.set exec-prefix : ~/work/boost/setup/boost_1_39_0/mybuild ; > option.set libdir : /lib ; > option.set includedir : ~/work/boost/setup/boost_1_39_0/mybuild/include > ; > The output of bootstrap.sh script instructs me to run ./bjam to build while instructions at the above link say to run ./bjam install Anyways, I tried both the options but every time I get the same error > Class top-level-target already defined > Aborted > I searched the forums, but this error seems to never be discussed. I am stuck, please help! Best regards, Aamir Ahmed Khan

1 0