- Boost-users - lists.preview.boost.org

Re: [Boost-users] statechart comparison
by Andreas Huber 01 Apr '09

01 Apr '09

Hi Brent > Is it still the case that boost statecharts require allocation and > destruction of a state object when entering and exiting that state? More precisely, the library issues "new State" upon state entry & and "delete State" upon state exit. So state construction & destruction *are* required but calls to global operator new and delete are not. The latter can be avoided by replacing operator new for your states or, on a more general level by passing a custom allocator to the state machine. Boost.Statechart was designed for reactive systems, where state machines are often serviced by dedicated threads. In such a scenario, the inter-thread communication usually introduces a much higher overhead than state construction & destruction. Regards, -- Andreas Huber When replying by private email, please remove the words spam and trap from the address shown in the header.

1 0

Re: [Boost-users] boost.statechart - a data driven state machine
by Andreas Huber 01 Apr '09

01 Apr '09

[snip] > I'd like this state machine to be completely data driven because it will > massively simplify testing and experimenting with different behaviours (ie. > I won't have to re-compile and produce new executables to try out a simple change). > > Instead of hard-coding all the states, events, transitions, etc., I would like > to read all those in from a config file (text, csv, xml, whatever). Boost.Statechart deliberately does not support dynamic configurability. The rationale can be found here: <http://www.boost.org/doc/libs/1_38_0/libs/statechart/doc/rationale.html#Dyn…> Regards, -- Andreas Huber When replying by private email, please remove the words spam and trap from the address shown in the header.

1 0

mpl::for_each state
by Skelly, Luke 01 Apr '09

01 Apr '09

Please ignore my last message. I somehow accidentally sent it while still editing! I am trying to create a std::map from an mpl::map. I've been trying to figure out how to use mpl::for_each to accomplish this. The problem I have is that the runtime function is passed to for_each by value and returns void. All the examples I've seen for mpl::for_each involve printing and not creating any new objects. Here is the attempt I've made: // creates std::map<size_t,size_t> from mpl::map<size_t,size_t> template<typename TypeMap> struct MapMaker { typedef std::map<size_t, size_t> map_type; map_type func_map; MapMaker() { boost::mpl::for_each<TypeMap>(*this); } template<typename U> void operator()(U x) { func_map[U::first::value]=U::second::value; } func_type operator[](size_t i) { return func_map[i]; } }; typedef boost::mpl::map< boost::mpl::pair<boost::mpl::size_t<1>, boost::mpl::size_t<2> >, boost::mpl::pair<boost::mpl::size_t<2>, boost::mpl::size_t<24> >, > myMap; int main() { MapMaker<myMap> m; size_t result = m[1]; } Of course this is a simplified version of what I'm really trying to do, which is create a map to function pointers. The problem is in the call to mpl::for_each in the MapMaker constructor. The std::map is created, but never returned. I've considered making func_map static, but that complicates things quite a bit, especially since MapMaker it is a class template. Luke Skelly

2 2

How to build signals2 with bjam?
by Stefan Funck 01 Apr '09

01 Apr '09

Hi all, I just checked out the current release from subversion and tried to build the signals2 lib with bjam --toolset=msvc --build-type=complete --with-signals2 stage but receive the message error: wrong library name 'signals2' in the --with-<library> option Building e.g. the thread or signals lib works fine. Does bjam have a list of "valid" libraries it checks against and signals2 is not yet contained in, or what am I doing wrong? Thanks for any help! Stefan

3 2

boost::regex ++ sequence is invalid
by jc 01 Apr '09

01 Apr '09

Hi, This is a carry over from the wrong group(boost build). In short the "+ +" sequence is invalid in boost::regex and valid in PRCE via an addition made to Perl 5.10. So, I am porting regular expressions that are used in PRCE and having trouble getting around this limitation in boost::regex. snip1: const boost::regex regex_username_password( "(" "(?:" "[a-zA-Z0-9_.!~*'()&=+$,;?/-]++" "|" "%[0-9a-fA-F]{2}" ")+" ")" "(?:" ":" "(" "(?:" "[a-zA-Z0-9_.!~*'()&=+$,-]++" "|" "%[0-9a-fA-F]{2}" ")*" ")" ")?" "@" ); snip2: const boost::regex regex_url_params("\\s*;([^?>]++)"); Help! -s7

1 0

Compiling Boost 1.38.0 with xlc 8.0 (Linux 64)
by Matthieu Brucher 01 Apr '09

01 Apr '09

Hi, I'm trying to use Boost on a PowerPC with IBM's compiler. Is there a .jam somewhere to use? Matthieu -- Information System Engineer, Ph.D. Website: http://matthieu-brucher.developpez.com/ Blogs: http://matt.eifelle.com and http://blog.developpez.com/?blog=92 LinkedIn: http://www.linkedin.com/in/matthieubrucher

1 0

Socket iostream Question
by Anthrope 01 Apr '09

01 Apr '09

Hello all, I am developing a high-performance socket-based application using the boost asio library. The application implements a binary tcp-based protocol that a bi-directional exchange of fixed-size messages. To simplify the coding while not sacrificing flexibility or performance, I decided to use the TCP iostream classes. The approach seems to work well, and I like the fact that the streams are buffered and allow me control over when I flush them. There's one minor issue that I thought I would seek some guidance on: Diagnosing and reporting failures connecting to servers are problematic. Basically, if a connect fails, the only way to know about it is to check the fail bit of the iostream. It would be nice to know why a client is unable to connect. So, to that end, I thought I could construct the iostream object via the default constructor, grab its streambuf via the rdbuf() call and in turn grab a basic_socket object reference to the streambuf and then call connect() on it, i.e., tcp::iostream iStream ; boost::asio::basic_socket_streambuf<tcp>& buf(*(iStream.rdbuf())); boost::asio::basic_socket<tcp, stream_socket_service<tcp> >& mySock(buf) ; mySock.connect(endPoint, error) ; The call to connect() on mySock with the error_code argument enables me to the diagnose and report connection problems a bit better. Once the connection is established, we can resume using the iostream directly. I would like to hear from you as to whether this approach makes sense, and what the pitfalls might be. And, alternative approaches would be most welcome too! Thanks in advance, Prashanth Nandavanam -- View this message in context: http://www.nabble.com/Socket-iostream-Question-tp22805249p22805249.html Sent from the Boost - Users mailing list archive at Nabble.com.

2 1

Is boost license GPL compatible?
by Tommy Nordgren 31 Mar '09

31 Mar '09

That is, is it possible to distribute a library distributed under the boost license together with a software package distributed under the GPL. ----------------------------------- See the amazing new SF reel: Invasion of the man eating cucumbers from outer space. On congratulations for a fantastic parody, the producer replies : "What parody?" Tommy Nordgren tommy.nordgren(a)comhem.se

3 2

zip_iterator and sTL algorithms like random_shuffle
by Andreas Fabri 31 Mar '09

31 Mar '09

Hello, I have two vectors and want to random_shuffle them the same way using the zip_iterator. I thought the code below would do it, but when I execute it I see that both sequences get screwded up. What do I wrong? Best regards, andreas #include <vector> #include <boost/iterator/zip_iterator.hpp> #include <algorithm> #include <iostream> int main() { std::vector<int> I(8), J(8); for(int i = 0; i < I.size(); i++){ I[i] = J[i] = i; } std::random_shuffle(boost::make_zip_iterator(boost::make_tuple(I.begin(), J.begin())), boost::make_zip_iterator(boost::make_tuple(I.end(), J.end()))); for(int i = 0; i < I.size(); i++){ std::cout << I[i] << " " << J[i] << std::endl; } return 0; }

3 5

[Q] scoped_ptr for forward declared classes
by V S P 31 Mar '09

31 Mar '09

Hello I have a situation where I have struct cmoney_impl_dtl; //hidden impl is in Cpp file struct myclass { boost::scoped_ptr<hidden_impl> myimpl_ptr; } The compiler complains that the struct hidden_impl must be fully defined in the header file (which I cannot do) ------------- c:\usr\local\boost.msvc2008\boost_1_38_0\boost\checked_delete.hpp(32) : error C2027: use of undefined type 'cmoney_impl_dtl' c:\dbt_money.hpp(38) : see declaration of 'cmoney_impl_dtl' c:\usr\local\boost.msvc2008\boost_1_38_0\boost\scoped_ptr.hpp(80) : see reference to function template instantiation 'void boost::checked_delete<T>(T *)' being compiled ------------- is there a way around this? I was trying to use shared_ptr there, but MSVC reports memory leak on those objects... so I must be doing something wrong there , and therefore just wanted to try a simple ptr. thanks in advance, Vlad -- V S P toreason(a)fastmail.fm -- http://www.fastmail.fm - Same, same, but different...

2 4

warnings with boost::bind
by Hansi 31 Mar '09

31 Mar '09

Hello, I have a question. I use boost::bind with the following class: class B { int data; } class A { bool SetData(const B&){return true;}; } now when I make somewhere the following: A a; boost::bind<bool>(&A::SetData,&a); I get a warning 8>D:\boost\boost_1_34_1\boost/bind.hpp(1575) : warning C4180: qualifier applied to function type has no meaning; ignored 8> D:\boost\boost_1_34_1\boost/bind.hpp(1609) : see reference to class template instantiation 'boost::_bi::add_cref<Pm,I>' being compiled 8> with 8> [ 8> Pm=bool (__thiscall Microtec::Program::* )(const Microtec::TrackingInfo &), 8> I=1 8> ] 8> .\Program.cpp(2385) : see reference to class template instantiation 'boost::_bi::dm_result<Pm,A1>' being compiled 8> with 8> [ 8> Pm=bool (__thiscall Microtec::Program::* )(const Microtec::TrackingInfo &), 8> A1=bool 8> ] I think it is for the const reference. Is this a problem? Is there some way to avoid it (okay the way with pragma I know)? I use boost 1.34.1 and MSVC2005 Regards

2 5

Cyclic includes when using smart pointers.
by Jared Lee Richardson 31 Mar '09

31 Mar '09

Hey, I'm having trouble with cyclic includes in a project I'm working on. This is my first attempt at a project that heavily uses boost, and specifically, smart pointers. I have the following situation, simplified down. Header file 1: class Test1 { vector<Test2Ptr> mTest2Objects; }; typedef boost::shared_ptr<Test1> Test1Ptr; Header file 2: class Test2 { vector<Test1Ptr> mTest1Objects; }; typedef boost::shared_ptr<Test2> Test2Ptr; Now normally I'd get around this easily by doing a forward declaration, but I can't do that with a smart pointer definition. How can I work around this? So far I have found ways to work around the above(Since that's not precisely what I'm doing), but when I start inlining functions it will become very difficult to work around. Obviously something is wrong with my include structure or how I am going about this, but I don't know what... Any help? Is there a way I can forward-declare smart pointers? How are complicated cyclic includes usually resolved, if forward declares aren't enough(i.e., inline files)? Thanks, Jared

2 3

[concept check][mpl] (Conditional) Concept checking for functions
by Jesse Perla 31 Mar '09

31 Mar '09

One rough idea I had was that since I will always have boost::function declarations as the default type, I could try to see if the type F is compatible with the boost::function type? Could this be done in a simple metafunction similar to the following: template<class BoostF, class F> struct CheckFunctionCompatible { static void Check() { F f; BoostF fboost = f; //If this fails, then I am basically failing } }; But then if I instantiate, won't it also try to instantiate the constructor? template<class F> class { typedef CheckFunctionCompatible<boost::function<double (double)>, F> test_F_compatibility; }; Of course, this wouldn't work for detecting the signature of the function, but that is a 2nd order feature for me. Of course, this also assumes that F can be constructed with no parameters, but this also might be reasonable for me if there is no better solution. -Jesse

2 2

TupleIt and zip_iterator
by Andreas Fabri 31 Mar '09

31 Mar '09

Was Anthony Williams TupleIt, mentioned in http://www.cpptalk.net/7-vt9657.html?postdays=0&postorder=asc&start=90 and distributed in http://groups.yahoo.com/group/boost/files/tupleit.zip) the precursor of the boost::zip_iterator? In contrast to the boost::zip_iterator an TupleIt iterator range can be sorted. What are the advantages of the zip_iterator, besides being in boost. andreas

1 0

Re: [Boost-users] [wave]include not found
by Ein Held 31 Mar '09

31 Mar '09

Here we go: http://rapidshare.com/files/215649826/wave.zip.html or http://uploaded.to/?id=ndz0tn

1 0

[Q] does map.erase destroy shared_ptr ?
by V S P 31 Mar '09

31 Mar '09

Hello, I am storing database streams as associated string tag as std::map< std::string, boost::shared_ptr<otl_stream> > once in a while I need to remove a stream based on the tag, so I do //find stream based on tag //close stream s->close //call map.erase can I expect that once I call map erase the destructor of the stream will get called? (for some reason I do not see my trace statement of the destructor, but the stream destruction are unfamiliar code to me.. so I may be just doing something wrong). thank you, Vlad -- V S P toreason(a)fastmail.fm -- http://www.fastmail.fm - Faster than the air-speed velocity of an unladen european swallow

2 1

Returning a shared_ptr or raw pointer from a template function
by Ryan McConnehey 31 Mar '09

31 Mar '09

I want to allow the user to specify if a function returns a raw pointer or a shared_ptr from a creation type function. The code I've started with is as follows: class Track{}; class Tm{}; template <class R, class T> R create(void) { R temp(new T()); return temp; } This allows to the user to call the function like: Tm* tm3 = create<Tm*, Tm>(); boost::shared_ptr<Tm> tm4 = create<boost::shared_ptr<Tm>, Tm>(); I would like to have a class that has this create function and upon creation of the class specify if the create function returns a raw pointer or shared_ptr. template <class U> //The U specifies is the create function returns a raw or shared pointer class Rdi { template <class S> U create(void) { U temp(new S()); return temp; } }; How would I modify this class to allow the user to make the following calls? Rdi<boost::shared_ptr> fun1; Tm* tm3 = fun1.create<Tm>(); Rdi<raw Pointer???> fun2; boost::shared_ptr<Tm> tm4 = fun2.create<Tm>(); Any help would be appreciated. Ryan

2 1

[wave]include not found
by Ein Held 31 Mar '09

31 Mar '09

Hello According to the wave documentation, the include folder functions of the context object work "are modelled after the command line behaviour implemented by the popular gcc compiler." Unfortunately this is wrong. By default gcc 4.x -Is' folders (when not used with -I-) are searched for "...." and <...> include files. Wave does not do so. Anyway, I am searching for a solution for this problem: Lets say I got a file named dub.cpp that I am parsing with wave and that looks like that: #include <foo/bar.hpp> int main{} bar.hpp looks like this: #include "test.hpp" extern int a; test.hpp is just an empty file in the same folder as bar.hpp I added the parent folder of foo to the wave context object via add_sysinclude_path . Unfortunately wave does not find the file test.hpp (exception - "error - could not find include file"). I tried nearly all possible combinations of add_include_path, add_sysinclude_path, set_sysinclude_delimiter - but I have not succeeded. This simple sample is still failing.. gcc -c -I"/foo/parent/folder" dub.cpp works fine though. Whats wrong?

2 1

Completely Perplexed Noob to BGL: Reachability Question
by Roshan Rammohan 31 Mar '09

31 Mar '09

Hi all, Although I was attracted to BGL since I have to use a lot of graph algorithms for my work, and I have managed to read through as much online documentation as possible, generic programming is still very mysterious to me. All I need to do is compute reachability from vertex B to vertex A before I add the edge A->B to a graph (directed and acyclic) so that I can maintain its acyclic property. I do not want to add the edge, discover a cycle and then remove it. I saw a very closely related example here. (thanks to Steven Watanabe) http://lists.boost.org/boost-users/2009/03/46396.php That was helpful, but I'm still not able to adapt this to my need mainly because I find the syntax and concepts of generic programming extremely confusing. I am not sure how I can pass an extra parameter into a BFSVisitor which the member function discover_vertex can use. Does discover_vertex have to have only a vertex_descriptor and a Graph? I want to pass another constant vertex to it so I can return on equality. I need to initiate a BFS from vertex B, (and not continue with new trees once the tree with B as root is finished) . On discovering vertex A in this search I need to return true, false for all other cases. Pretty simple, and I am hoping someone would write a code snippet for me that will solve the problem and also provide me with the baby step I need to wrap my head around this Visitor concept. Thanks in advance. - Roshan Rammohan PhD Candidate, A.I. lab, Dept of C.S., Univ. of New Mexico, USA

6 6

[statechart] state behaviour
by liquid 30 Mar '09

30 Mar '09

Hi, two questions about states in statechart: 1. How (if possible) to implement this: a state upon an event generates an event and transits to another state? 2. Can a state have private nondestroyable memory? Regards liquid

2 2

Re: [Boost-users] regex iterator question
by Mike Marchywka 30 Mar '09

30 Mar '09

---------------------------------------- > To: boost-users(a)lists.boost.org > Date: Mon, 30 Mar 2009 12:48:48 -0400 > From: dfs(a)savarese.org > Subject: Re: [Boost-users] regex iterator question > > > In message , "Robert Ramey" writes: >>Thinking about it, this problem must come very often. How is it usually >>addressed? There must be a simple bridge across this. In a pinch, I'll >>just have to load the whole file into some sort collection, but I prefer the >>ultimate unlimited file size solution. > I always like unbounded solutions too but if you try to stream a file past a regex-er it is likely to be slow, and as pointed out by others, not even reasonable in the general case although you may want to think about specialized cases that may benefit from any restricted set of regex'es you have. You would have to think about "strategies" or similar notions that look at the problem and pick an approach or specific implementation based on parameters. I originally came here to do 1000's of REGEX queries on megabyte strings and ultimately used Boost and Greta for testing but quickly found ways to compile query/sample vectors and implement restricted searches once I found all the not-so-regular expressions fit a given constraint or could even do simple things like sorts to preserve locality later. There are a lot of potential performance limitations depending on the specific task parameters and machine. But, yes, it would be nice if someone had a general "strategy" library. LOL. > In the worst case, if you're using Perl-style expressions (or any style > that isn't strictly "regular" and requires backtracking; lookahead > assertions are a common culprit), the entire input may have to be > consumed and buffered even if the expression ultimately matches only a > few characters (see "On the Use of Regular Expressions for Searching Text", > Clark and Cormack, ACM Transactions on Programming Languages and Systems, > Vol 19, No. 3, pp 413-426.). Therefore, if you're dealing with small > files, you may as well buffer the entire file in a char array and use > regex_token_iterator. If you're dealing with large files, > memory map the file instead. > > daniel > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users _________________________________________________________________ Internet Explorer 8 – Get your Hotmail Accelerated. Download free! http://clk.atdmt.com/MRT/go/141323790/direct/01/

2 2

Re: [Boost-users] Using boost regex dll in code
by John Maddock 30 Mar '09

30 Mar '09

> Is there a way to contact you directly? I believe my confusion can be > solved rather quickly w/o using the user groups. You can use the john - at - johnmaddock.co.uk address to mail me directly, but I'll be offline for the day very shortly, Regards, John.

1 0

regex iterator question
by Robert Ramey 30 Mar '09

30 Mar '09

I've got a need for regex and I would like to use it to extract tokens matching a regular expresssion from a file stream. Seems like this would be a common desire. So first shot is boost::regex_token_iterator<some_input_iterator> This doesn't work since regex_token_iterator requires a bidirectional iterator. Seems reasonable enough. So next I comb through boost and find #include <boost/spirit/iterator/multi_pass.hpp> and try boost::regex_token_iterator< boost::spirit::multi_pass<some_input_iterator> > I'm thinking this is veeeeeery cool - maybe a 1000 lines of free code included for the price of one. But, doesn't work. multi_pass is a forward_trasversal iterator while regex_token_iterator requires a bidirectional_trasversal_iterator. A huge disappoint to come soooo close. Thinking about it, this problem must come very often. How is it usually addressed? There must be a simple bridge across this. In a pinch, I'll just have to load the whole file into some sort collection, but I prefer the ultimate unlimited file size solution. Robert Ramey

3 3

boost.statechart - a data driven state machine
by dev＠kostiadis.com 30 Mar '09

30 Mar '09

Hello all, I'm using the statechart library to create a generic state machine that I can reuse in a number of projects. I'd like this state machine to be completely data driven because it will massively simplify testing and experimenting with different behaviours (i.e. I won't have to re-compile and produce new executables to try out a simple change). Instead of hard-coding all the states, events, transitions, etc., I would like to read all those in from a config file (text, csv, xml, whatever). I'm pretty sure I can't be the first person to want this. Is there an implementation of this out there somewhere? Are there any docs/links/etc. that will point me to the right direction? Thank you in advance, k.

1 0

Problem using Boost->String->Split
by professor rumsdiegeige 30 Mar '09

30 Mar '09

Hello, using Visual Studio 2005 and Boost 1.31, I'm trying to compile this: #include <boost/algorithm/string.hpp> #include <boost/algorithm/string/split.hpp> #include <vector> #include <string> using namespace boost::algorithm; typedef vector< string > split_vector_type; split_vector_type SplitVec; std::string r = std::string(sc); boost::algorithm::split( SplitVec, r, boost::algorithm::is_any_of(sep) ); But I get: error C2039: 'iterator': is not a member of "global namespace'' in iterator.hpp 37 What's wrong here? Thanx! Sabine Lorentz

2 3