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Can any one help me with this fstream
by ch.asad＠gmail.com 02 Jan '10

02 Jan '10

Hi i am new to boost. i have written a code. can any one guide me whats the issue with this code. It gives an error when I assign the File pointer to a Global poiter. " h_file = file; h_str = str; " Can any one guide me whats the issue with this and how cna i solve this issue. thanks, Asad // Accelor-test.cpp : Defines the entry point for the console application. // #include <iostream> #include <string> #include <fstream> #include <string> #include <vector> #include <iostream> #include <iterator> #include <functional> #include <boost/asio.hpp> #include <boost/algorithm/string/classification.hpp> #include <boost/algorithm/string/split.hpp> #include <boost/algorithm/string/find_iterator.hpp> #include <boost/thread/thread.hpp> using boost::asio::ip::tcp; using namespace std; using namespace boost; std::fstream h_file; int hb; int cnt; tcp::iostream h_str; //boost::mutex mutex; void Accelor_test() { std::cout<<"\nAPP started ...\n"; char ver[100]; char s1[100]; vector<std::string> strng,st,u_p; //int ef; h_str.read(ver,sizeof(ver)); std::cout<<" INBOUND : Version read : " <<ver<<std::endl; h_file.getline(s1,sizeof(s1)); std::cout<<s1<<std::endl; } void send_HB() { std::cout<<"\nHeart Beat Started..."; // boost::mutex::scoped_lock lock(mutex); char h_b[] = "HB\n"; for(;;) { boost::xtime xt; boost::xtime_get(&xt, boost::TIME_UTC); xt.sec += 1; h_str.write(h_b,sizeof(h_b)); boost::thread::sleep(xt); std::cout <<"OUTBOUND : HB ,"<< ++cnt << std::endl; } } int main(int argc, char* argv[]) { std::fstream file = std::fstream("inttest_sample.csv",std::fstream::in); if(h_file == NULL) { std::cout<<"File not found"; } char s1[100]; vector<std::string> conf,connection,u_p; int ef; h_file.getline(s1,sizeof(s1)); std::cout<<"s1 = "<<s1<<endl; std::cout<<"Split Conf"; split(conf, s1, is_any_of(","), token_compress_on); split(connection, conf[0], is_any_of(":"), token_compress_on); tcp::iostream str(connection[0],connection[1]); h_file = file; h_str = str; boost::thread thrd_hb(&send_HB); boost::thread thrd_acc(&Accelor_test); thrd_hb.join(); thrd_acc.join(); file.close(); str.close(); //std::cout<<"kjdshkjf"; } -- View this message in context: http://old.nabble.com/Can-any-one-help-me-with-this-fstream-tp26986763p2698… Sent from the Boost - Dev mailing list archive at Nabble.com.

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[any] New feature idea for boost.any
by Andres B. 01 Jan '10

01 Jan '10

Hello, i am Andrés, i am new in the boost world and i have an idea to boost.any. With the actual boost::any i can't do this: boost::any any_var; int i; any_var = 10; i = 1 + any_var; double d; // d = 1.0 + any_var; // throw: bad_any_cast, because any_var is int any_var = 10.0; d = 1.0 + any_var - 3.0; // now any_var is double because are incompatible types. To solve this problem, we need add the casting operator and add overload the global operators. I wrote the code and actually have the global operators overloaded +, -, *, /, %. I don't know how write code to Boost, for this reason maybe has errors. namespase boost { class any { //.... public: // casting operators template <class ValueType> operator ValueType () const { return boost::any_cast<ValueType>(*this); } template <class ValueType> operator ValueType () { return boost::any_cast<ValueType>(*this); } // arithmetic operators template <typename ValueType> ValueType operator+ (const ValueType& t1) const { return (ValueType)(*this) + t1; } template <typename ValueType> ValueType operator- (const ValueType& t1) const { return (ValueType)(*this) - t1; } template <typename ValueType> ValueType operator* (const ValueType& t1) const { return (ValueType)(*this) * t1; } template <typename ValueType> ValueType operator/ (const ValueType& t1) const { return (ValueType)(*this) / t1; } template <typename ValueType> ValueType operator% (const ValueType& t1) const { return (ValueType)(*this) % t1; } //... } // End any //... // Global operators template <class ValueType> ValueType operator+ (ValueType t1, boost::any t2) { return t1 + (ValueType)(t2); } template <class ValueType> ValueType operator- (ValueType t1, boost::any t2) { return t1 - (ValueType)(t2); } template <class ValueType> ValueType operator* (ValueType t1, boost::any t2) { return t1 * (ValueType)(t2); } template <class ValueType> ValueType operator/ (ValueType t1, boost::any t2) { return t1 - (ValueType)(t2); } template <class ValueType> ValueType operator% (ValueType t1, boost::any t2) { return t1 % (ValueType)(t2); } } If you like it or not, please tell me. Excuse my English

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linear algebra (and matrix) library (again)
by DE 31 Dec '09

31 Dec '09

hi again i worked on a linear algebra library there are almost fully working prototype and its documentation in the vault (BIBLAL) http://www.boostpro.com/vault/index.php?direction=0&order=&directory=linalg& i would appreciate your interest and feedback -- Pavel ps happy new year!

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Re: [boost] [date_time] quarters as new durations?
by pete＠pcbartlett.com 31 Dec '09

31 Dec '09

On Tue 22/12/09 13:54 , "Stewart, Robert" <Robert.Stewart(a)sig.com> wrote: > wrote: > > On Tue 22/12/09 13:27 , "Stewart, Robert" wrote: > > > Jeff Garland wrote: > > > > > > > > Month durations play some games to handle this problem (see > > > > docs for details) which quarters could adopt. But if you > > > > adopt the month rules then I don't thing you buy much more > > > > than simply writing > > > > > > > > const months quarters = months(3); > > > > > That's an excellent point. I don't think the fuzzy math > approach is > > > appropriate for quarters because they have a precise definition: > 1/4 > > > of a year. Months are less precise, though 365 / 4 is not a > whole > > > number, of course. > > > > Possibly opening a can of worms here, but a quarter in my > > line of work is invariably three months. If your mileage > > varies, then there could be a problem in providing a fully > > meaningful quarter duration type if people think it means > > different things. > Jeff's idea of months(3) is all you need, right? Yup, and in fact I use exactly that approach at the moment. A new duration type with quarter in the name that meant something other than three months could serve to confuse as much as it helps though, IMO.

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GPL and boost
by Stefan Strasser 31 Dec '09

31 Dec '09

Hi, is there a precedent of optional(!) external library dependencies to GPLed libraries in boost? IIUC the implementation of the interface to the library in boost would constitute a derivative work of the GPLed library and therefore be "infected" by it. do the terms of the GPL then only apply if a boost user is actually using this optional code and linking to the external library or does this inhibit the distribution of such code with boost releases in general? and if so, is external distribution, e.g. in the vault, but documentation in the main library acceptable? I'm asking because of a possible interface to Oracle's Berkeley DB, but I guess this will come up again with Boost.Rdb and GPLed SQL databases.

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Linking Errors in Boost Logging
by nsk＠umd.edu 31 Dec '09

31 Dec '09

Hi, I am a beginner in using the Boost Libraries. I came across them when I was trying to implement the Boost Logging Framework version2 from John Torjo's website. I tried implementing the starter project(http://torjo.com/log2/doc/html/starter_project.html) from Boost Log documentation using Visual Studios 2005 IDE. I got the following 2 errors: error C2440: '<function-style-cast>' : cannot convert from 'const char [13]' to 'boost::logging::formatter::tag::time' and error C2780: 'void boost::logging::writer::format_write<formatter_base,destinatio n_base,lock_resource,apply_format_and_write,router_type,format ter_array,destination_array>::add_formatter(formatter,const boost::logging::char_type *)' : expects 2 arguments - 1 provided So, I commented the formatter::tag::time line assuming that I don't need time to be displayed for the time being. The program complied properly but it gave me link errors: error LNK2019: unresolved external symbol "struct boost::logging::filter::use_tss_with_cache<10> * __cdecl g_l_filter(void)" (?g_l_filter@@YAPAU? $use_tss_with_cache@$09@filter@logging@boost@@XZ) referenced in function "void __cdecl `anonymous namespace'::`dynamic initializer for 'ensure_log_is_created_before_maing_l_filter''(void)" (?? __Eensure_log_is_created_before_maing_l_filter@? A0x6e6fd73c@@YAXXZ) my_app_log.obj and error LNK2019: unresolved external symbol _main referenced in function ___tmainCRTStartup MSVCRTD.lib Please let me know whether I am missing some linker dependencies. Please help! -Nik Kale

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Major code changes deadline approaching
by Vladimir Prus 30 Dec '09

30 Dec '09

Boosters, The deadline for "major code changes" for 1.42 is Monday, January 4, 2010. Please try to get all big features merged to release branch by that date, and let the release team know if there are any issues. The next deadline will be Jan 11, when the release branch will be closed for all changes, except by explicit permission. -- The Release Managers, Beman Dawes Daniel James Eric Niebler Rene Rivera Vladimir Prus

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is_explicitly_convertible
by Daniel Frey 29 Dec '09

29 Dec '09

Just in case someone's interested: I implemented is_explicitly_convertible for GCC 4.4+ (4.3 doesn't work). Since it uses lots of C++0x-ish stuff, it is likely not a good addition to boost::type_traits, but I figured the people here might be interested anyway :) #include <type_traits> namespace boost { namespace impl { template< typename T > T make(); template< typename From, typename To > decltype( To( make< From >() ), make< std::true_type >() ) select( int ); template< typename, typename > std::false_type select( ... ); } template< typename From, typename To > struct is_explicitly_convertible : std::is_same< decltype( impl::select< From, To >( 0 ) ), std::true_type > { }; } struct X { X( double& ); explicit X( int& ); }; #define STATIC_ASSERT( X ) static_assert( X, #X ) int main() { STATIC_ASSERT(( boost::is_explicitly_convertible< double&, X >::value )); STATIC_ASSERT(( boost::is_explicitly_convertible< int&, X >::value )); STATIC_ASSERT(( !boost::is_explicitly_convertible< void*, X >::value )); } Regards, Daniel

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boost::serialization, binary archive contents
by Dan 29 Dec '09

29 Dec '09

Hi All, Im not sure if this the correct mailing list or not.. in fact im not sure if i'm even going about this the right way.. forums are so much easier.. Im using the boost::serialization library, im attempting to serialize an image file from the freeimage library. It is working beautifully if i serialize to a text archive however, binary archives fail to load with a "stream error" exception. With the freeimage library i can save the image to memory and then retrieve the pointer to the start memory address and also retrieve the size. With this information I attempt the following (NOTE, "io" is the freeimage memory stream (fipMemoryIO) which is returning the memory pointer and the size): void save(Archive & ar, const unsigned int version) const { BYTE * pData; DWORD dwSize; io.acquire(&pData1, &dwSize); ar & dwSize; boost::serialization::array<BYTE> ao = boost::serialization::make_array<BYTE>(pData, dwSize); ar & ao; } void load(Archive & ar, const unsigned int version) { BYTE * pData; DWORD dwSize; ar & dwSize; pData = new BYTE[dwSize]; boost::serialization::array<BYTE> ao = boost::serialization::make_array<BYTE>(pData, dwSize); ar & ao; // <----------- This throws an exception } The above throws the exception.. even though it succeeds with a text archive. What is even more frustrating is that if (when saving) the contents pData1 points to are changed, when loading there is no exception. (Obviously the bitmap would be corrupt but thats beside the point). void save(Archive & ar, const unsigned int version) const { BYTE * pData; DWORD dwSize; io.acquire(&pData1, &dwSize); ar & dwSize; memset(pData1, 0xAB, dwSize); // <--- Add this line an no exception is thrown. boost::serialization::array<BYTE> ao = boost::serialization::make_array<BYTE>(pData, dwSize); ar & ao; } I am at a loss. If i want to write x number of bytes it should write x number of bytes no matter what those bytes are.. I must be doing something wrong because this just doesnt make sense. The exception is always thrown in basic_binary_iprimitve.hpp if(scount != s) boost::serialization::throw_exception( archive_exception(archive_exception::stream_error) ); Regards, Dan

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[typeof] Determining if a type has been registered or not at compile time
by Edward Diener 27 Dec '09

27 Dec '09

Is there any way one can determine whether a type has been registered or not with Boost.Typeof at compile time so that the information can be used in TMP ? I am thinking, of course, of the use of typeof in a template, where a template parameter may or may not be aregistered type when the template has been instantiated. I would like to provide my own TMP fallback code if the type has not been registered rather than see an immediate compiler error generated. Something like: boost::mpl::eval_if < boost::typeof::registered<T>, // this would be nice to have boost::mpl::identity<BOOST_TYPEOF_TPL(some_expression)>, boost::mpl::identity</* use another facility to get the type I want into a metafunction*/> >

2 4

Interest check: Boost.Mock
by Peter Bindels 26 Dec '09

26 Dec '09

Hi all, Over the past three-quarters of a year I've been working (with three friends) on a mocking framework for C++. In our vision, it would be a good complement to Boost.Test for testing classes separate from interfaces required - it would improve the ability to unit-test the classes that tie others together and that implement higher-level algorithms. It does this by creating an object that is "derived" from a given class at runtime, and replacing the functions with functions that redirect to verifying logic. The verifying logic uses basic structures to record expectations and to verify they happened. These ways of creating an object at runtime and modifying it are highly compiler dependant but remarkably portable - as it runs on at least 3 different compiler series (GCC, MSVC, EDG-based) and 5 platforms (Windows XP, Windows CE, Linux, QNX, bare platform), with few modifications. The library has been released under the name "Hippo Mocks" already. I'm interested in submitting it to Boost for three reasons. First of all, I believe that there may be obvious or very interesting optimizations or expansions I do not notice. Second, as Christian has elaborated on already, having the Boost tag on the project makes it more noticed and more used. As it has taken quite a bit of time from me already I would like people to use it. Third, Boost.Test allows testing code but does not support mocking. In the environment of unit testing, anything that is not a base library benefits from mocking by abstracting away details that are irrelevant and that will break your test unnecessarily. For Boost the main changes would be superficial in the naming and in using more default libraries instead of a new implementation. For Hippo Mocks I've decided to make no assumptions in anything over C++98 so there's a full Tuple implementation and so on. If there's an interest I'll spend the evening porting the code to qualify for the Boost coding norms and upload it to the vault (if I can - but that should be OK). I would like you to take a look at the code and tell me what you think of it. Thanks for your time. Kind regards, Peter Bindels

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Information about BMock
by Sterkin, Asher 24 Dec '09

24 Dec '09

Gennady, Recently I've came across discussion about extending the Boost.Test framework with a mocking capabilities: http://old.nabble.com/Interest-check:-Boost.Mock-td23958875.html I've even found a new header file mock_object.hpp within the 1_41 distribution, but not any documentation yet. There was a question about BMock library I developed and presented about at BoostCon09. The main differentiator of BMock from the rest of C++ frameworks I'm familiar with (except maybe MockItNow) is that it does not require neither classes, nor virtual methods. It does use heavily BOOST.Preprocessor and, at certain degree, boost meta-programming capabilities. Even though it has some historical quirks BMock has two major advantages, in my view, unsurpassable yet: a) Ability to dynamically mock ANY function or method. The function definition header needs to be wrapped with a special BMOCK_FUNCTION macro. Opposite to MockItNow this proves a fully portable solution, which does not depend on profiler API or any other low-level compiler capabilities. a) Deep integration with Boost.Test library, most importantly with its diagnostics. So far it proved itself as an extremely useful tool for embedded software development in C/C++. Attached you will find BMock documentation (sorry, not Boost standard :(). Not everything is relevant and not everything should remain, but hopefully you will get an adequate impression about how does it work from the user perspective. As I explained it to Dave during the BoostCon 09 I do not think that BMock in its current state is suitable to be a separate contribution to the Boost library, nor do I think it should be. From the beginning the BMock was conceived as a lightweight (well, as much as possible) extension to Boost.Test. If you find it interesting I will be happy to send you all sources (not too much) and to discuss how to proceed further. Regards, Asher Sterkin Asher [cid:image001.png@01CA84E9.267C30C0] <http://twitter.com/asterkin> [cid:image002.png@01CA84E9.267C30C0] <http://www.twitpic.com/photos/asterkin> [cid:image003.png@01CA84E9.267C30C0] <http://disturbingthoughts-asher.blogspot.com/> [cid:image004.gif@01CA84E9.267C30C0] <http://www.linkedin.com/pub/asher-sterkin/3/106/10a> ________________________________ This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the postmaster(a)nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes. To protect the environment please do not print this e-mail unless necessary. An NDS Group Limited company. www.nds.com Gennady, Recently I’ve came across discussion about extending the Boost.Test framework with a mocking capabilities: [1]http://old.nabble.com/Interest-check:-Boost.Mock-td23958875.html I’ve even found a new header file mock_object.hpp within the 1_41 distribution, but not any documentation yet. There was a question about BMock library I developed and presented about at BoostCon09. The main differentiator of BMock from the rest of C++ frameworks I’m familiar with (except maybe MockItNow) is that it does not require neither classes, nor virtual methods. It does use heavily BOOST.Preprocessor and, at certain degree, boost meta-programming capabilities. Even though it has some historical quirks BMock has two major advantages, in my view, unsurpassable yet: a) Ability to dynamically mock ANY function or method. The function definition header needs to be wrapped with a special BMOCK_FUNCTION macro. Opposite to MockItNow this proves a fully portable solution, which does not depend on profiler API or any other low-level compiler capabilities. a) Deep integration with Boost.Test library, most importantly with its diagnostics. So far it proved itself as an extremely useful tool for embedded software development in C/C++. Attached you will find BMock documentation (sorry, not Boost standard L). Not everything is relevant and not everything should remain, but hopefully you will get an adequate impression about how does it work from the user perspective. As I explained it to Dave during the BoostCon 09 I do not think that BMock in its current state is suitable to be a separate contribution to the Boost library, nor do I think it should be. From the beginning the BMock was conceived as a lightweight (well, as much as possible) extension to Boost.Test. If you find it interesting I will be happy to send you all sources (not too much) and to discuss how to proceed further. Regards, Asher Sterkin Asher [2]twitter [3]twitpic [4]favicon [5]Linkedin _________________________________________________________________ This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the postmaster(a)nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes. To protect the environment please do not print this e-mail unless necessary. An NDS Group Limited company. www.nds.com References 1. http://old.nabble.com/Interest-check:-Boost.Mock-td23958875.html 2. http://twitter.com/asterkin 3. http://www.twitpic.com/photos/asterkin 4. http://disturbingthoughts-asher.blogspot.com/ 5. http://www.linkedin.com/pub/asher-sterkin/3/106/10a

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[optional] Strict Aliasing Warnings on Trunk
by Dean Michael Berris 24 Dec '09

24 Dec '09

I've recently been seeing this error more and more especially on GCC with -Wall: /home/dean/boost/boost/optional/optional.hpp:407: warning: dereferencing pointer ‘<anonymous>’ does break strict-aliasing rules /home/dean/boost/boost/optional/optional.hpp:427: note: initialized from here and: /home/dean/boost/boost/function/function_base.hpp:321: warning: dereferencing type-punned pointer will break strict-aliasing rules /home/dean/boost/boost/function/function_base.hpp:325: warning: dereferencing type-punned pointer will break strict-aliasing rules This is on Linux and GCC 4.4.1. I'm not an expert in this regard but is there a way to either silence or avoid these warnings? Anything you want me to try from my end? Thanks in advance and I hope this helps. -- Dean Michael Berris blog.cplusplus-soup.com | twitter.com/mikhailberis linkedin.com/in/mikhailberis | facebook.com/dean.berris | deanberris.com

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Using Boost.Atomic for shared_ptr
by Phil Endecott 24 Dec '09

24 Dec '09

Dear All, I have just had a quick look at how easily shared_ptr could be adapted to use Helge's proposed Boost.Atomic. To me it looks very simple, but maybe someone who knows more about all this could have a look? I took the non-threaded implementation in sp_counted_base_nt.hpp as a starting point, and simply changed the two counts from long to boost::atomic<long> : boost::atomic<long> use_count_; // #shared boost::atomic<long> weak_count_; // #weak + (#shared != 0) Then, the majority of the methods don't need to change since the atomic template provides atomic versions of e.g. operator++. The one that does need more work is add_ref_lock, which I've implemented as follows: bool add_ref_lock() // true on success { while (1) { long c = use_count_; if (c == 0) return false; if (use_count_.compare_exchange_weak(c,c+1)) return true; } } There is also the question of memory barriers. I understand that things like operator++ provide the most pessimistic memory barriers, so ideally these should be replaced with calls that use the right barriers. Does anyone have any thoughts about how this would compare with the current custom assembler implementations? Cheers, Phil.

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[fusion] change on trunk breaking proto
by Eric Niebler 23 Dec '09

23 Dec '09

Hi Fusion gurus. I'm chasing an elusive bug that the following Proto test has exposed: http://beta.boost.org/development/tests/trunk/developer/output/RW_WinXP_VC-… All is well on the release branch, but on trunk, Proto's examples.cpp test is failing -- but only on MSVC! I suspect Fusion because if I replace the version of Fusion on trunk with the one on release all is well. (Caveat: when I do this, I also need to make a corresponding change to the as_callable function object in proto/transform/fold.hpp to accommodate the changed argument order of fusion::fold's functor.) It seems something is causing MSVC to prematurely instantiate a template used in a Proto transform, but I can't see what. I first suspected the recent changes to fusion::fold, but that seems not to be the case. If I just take the release version of fusion::fold, the problem still manifests. The problem must be elsewhere. Does anyone from Fusion team want to give this a crack? I'll be happy to help. -- Eric Niebler BoostPro Computing http://www.boostpro.com

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Interprocess message queue implementation
by Alex Miller 22 Dec '09

22 Dec '09

Hello, I have been looking over the implementation of Boost.Interprocess's message queues, and have become slightly confused as to the reasoning for how it was designed. Assuming my understanding is correct, it allocates a piece of shared memory, and then constructs a message queue within that piece of memory. Is there a reason that this was done in favor over implementing it by using SystemV's message queues ( the one located in <sys/msg.h> )? Thanks, Alex Miller

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Re: [boost] [date_time] quarters as new durations?
by pete＠pcbartlett.com 22 Dec '09

22 Dec '09

On Tue 22/12/09 13:27 , "Stewart, Robert" <Robert.Stewart(a)sig.com> wrote: > Jeff Garland wrote: > > Stewart, Robert wrote: > > > Thomas Lemm wrote: > > >> I am happily using the boost date_time library and I plan to > > >> extend it towards including quarters as new (gregorian) date > > >> durations, just the way months are included already > > >> (excluding parsing of quarters) > > > > > > Why excluding parsing? That would imply only partial > > > support relative to other durations, right? > > > > > Well, so quarters turns out to be like months as far as > > durations go -- that is, it's mathematical like days and > > weeks. So the big drawback you face is dealing with the > > associated "fuzzy math". For example, what's the result > > of > > > > date("2008-Feb-28") + quarters(1) = ? > > date("2008-Feb-27") + quarters(1) = ? > > > > Month durations play some games to handle this problem (see > > docs for details) which quarters could adopt. But if you > > adopt the month rules then I don't thing you buy much more > > than simply writing > > > > const months quarters = months(3); > That's an excellent point. I don't think the fuzzy math approach is > appropriate for quarters because they have a precise definition: 1/4 > of a year. Months are less precise, though 365 / 4 is not a whole > number, of course. Possibly opening a can of worms here, but a quarter in my line of work is invariably three months. If your mileage varies, then there could be a problem in providing a fully meaningful quarter duration type if people think it means different things. > There is probably still a need to use some fuzzy math in order to > determine the calendar date for quarter boundaries. Quarters are > usually associated with a fiscal year and there are different > definitions of those, so you probably need to add fiscal year support > and make quarters a derived concept. > > There's also an argument against adding quarters as a > > duration. I have an app somewhere in which I have quarter > > defined as a date_period so I could write: > > > > date_period q = quarter(2009, 1); > > > > To me at least this seems like the more likely application. > I agree. I didn't consider the ramifications of duration versus > period. The issue routinely occurs with months already though. Month durations and date_periods spanning a specific month already have to work closely with each other: date_period month_containing(date d) { return date_period(date(d.year(),d.month(),1) , months(1) ); } so it may not be a big issue.

2 1

[date_time] quarters as new durations?
by Thomas Lemm 22 Dec '09

22 Dec '09

Hi, I am happily using the boost date_time library and I plan to extend it towards including quarters as new (gregorian) date durations, just the way months are included already (excluding parsing of quarters) Now my question: What are the chances that his change might make it into the boost date_time library? Is there some interest in this feature, if so I would provide a patch to update source and documentation to include the quarters as a new duration. Please let me know, Kind regards Thomas Lemm

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[ANN] CLI 1.1.0 released
by Boris Kolpackov 21 Dec '09

21 Dec '09

Hi, Seeing that I've got a lot of useful feedback for the initial release, I am pleased to announce the availability of CLI 1.1.0. CLI is an open-source (MIT license), cross-platform command line interface compiler for C++. It allows you to specify the options that your program supports, their types, default values, and documentation. This specification can then be automatically translated to C++ classes that implement parsing of the command line arguments and provide a convenient and type-safe interface for accessing the extracted data. The automatic usage and documentation generation is by far the biggest new feature in this release. The usage information is formatted during compilation and the documentation can be generated in the HTML and man page formats. For an example of the HTML output, see the documentation for the CLI compiler itself (you may also want to check the cli.1 man page and the usage information printed by the compiler): http://www.codesynthesis.com/projects/cli/doc/cli.xhtml Other new features in this release: * Optional generation of modifiers in addition to accessors. * Support for erasing the parsed elements from the argv array. * Support for custom argument sources via an abstract scanner interface. * Support for reading command line arguments from the argv array as well as files specified with command line options. For a more detailed list of new features in this release see: http://www.codesynthesis.com/pipermail/cli-users/2009-December/000001.html More information, documentation, and source code distributions are available from the project's web page: http://www.codesynthesis.com/projects/cli/ Enjoy, Boris -- Boris Kolpackov, Code Synthesis http://codesynthesis.com/~boris/blog Open-source XML data binding for C++ http://codesynthesis.com/products/xsd XML data binding for embedded systems http://codesynthesis.com/products/xsde Command line interface to C++ compiler http://codesynthesis.com/projects/cli

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[serialization] optional serialization and non-default-constructables
by Felipe Magno de Almeida 21 Dec '09

21 Dec '09

Hello, serialization for boost.optional calls load_construct_data but doesn't call save_construct_data. Which causes serialization for non-default-constructables to break. Regards, -- Felipe Magno de Almeida

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Re: [boost] [msm] Review
by Christophe Henry 21 Dec '09

21 Dec '09

>> You brought 2 reasons for this impossibility: >> 1. Automatic entry/exit. You answer that "With separate FSMs you'd >> have to manage this yourself". >> 2. Automatic event dispatch. You answer that "Again, with separate >> FSMs you'd have to do that yourself (dispatch to first FSM and if that >> didn't consume the event, dispatch to second FSM and so on)." > > It appears that you should read the 2005 post a lot more carefully, > especially the quoted context. The remarks you quote above have *nothing* to > do with the impossibility I claimed. No, I won't spend "a lot more" time trying to decipher the supposedly hidden meaning of your post and invest the time more wisely by making MSM more useful. The link I added seems quite clear to me and anyone interested can make himself his own opinion by opening it. You did not bother bringing an argumentation disproving my claim, so I will simply keep it. As you also didn't address the more important technical part (multiple TU) of my answer, I will consider it accepted.

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What about "Maybe" ?
by Arnaud Masserann 21 Dec '09

21 Dec '09

Hi, Is there any interest for a "Maybe" utility class, like the one in Haskell ? For those who don't know about Maybe, here is the Haskell ref : http://www.haskell.org/ghc/docs/6.10.4/html/libraries/base/Prelude.html#t%3… And a code snippet showing its use : http://pastebin.com/m3a590d6e Arnaud

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How to detect if f() returns void or not?
by Frédéric Bron 21 Dec '09

21 Dec '09

I would like to detect if the return type of a function is void or not within C++03 standard? I need that to implement new type traits to detect if types can be compared and to detect for example operator< returning void. The following code compiles only with c++0x standard and keyword decltype but not with c++03 standard and BOOST_TYPEOF. Frédéric #include <iostream> #include <boost/type_traits/is_void.hpp> #include <boost/typeof/typeof.hpp> void returns_void(); int returns_int(); int main() { std::cout<<std::boolalpha; // std::cout<<boost::is_void< BOOST_TYPEOF(returns_void()) >::value<<'\n'; // std::cout<<boost::is_void< BOOST_TYPEOF(returns_int()) >::value<<'\n'; std::cout<<boost::is_void< decltype(returns_void()) >::value<<'\n'; std::cout<<boost::is_void< decltype(returns_int()) >::value<<'\n'; return 0; }

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[bind] Function call operator is a template?!
by Andy Venikov 20 Dec '09

20 Dec '09

All this time I've been using bind quite happily without really going into the details of its implementation. Recently, however, I had to discover the hard way that the function call operator that is produced as part of the bind() return is a template! I guess most of the time one would not care if it's a template or not as long as you can call the resulting functor with the right signature. It does, however, make a difference. The difference can be seen when calling the resulting functor with wrong arguments. The error detection happens earlier in the case when functor's operator() is a concrete function as opposed to a template. And that plays bad tricks with SFINAE. You see, recently I was faced with a challenge where I had to check at compile time whether calling a template argument with a specific signature is a well-formed expression. Something similar to Eric Niebler's "can_be_called<>": http://www.boost.org/doc/libs/1_41_0/doc/html/proto/appendices.html#boost_p… Well, this technique won't work with bind(), because the template member operator() will happily accept ANY argument during SFINAE and the error detection will happen much later, when you actually try to call the functor. I'm not going to debate whether it's right or wrong, but I'm still curious - why did it have to be a template? When bind() is called it already has all the information about the function's signature so it could construct a concrete member operator() without resorting to templates. For example bind(main) could easily determine that the signature is <int (int, char * [])> and could create a functor with a single "int operator()(int, char *[])", instead of a template. It's not like it's lambdas, where when you say _1 + _2 you literally mean parameters of any type. Thanks, Andy.

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getting errors whti boost.
by ch.asad＠gmail.com 19 Dec '09

19 Dec '09

Hi I am getting errors when i ininclude boost header file in my project. my progrm is running fine. I want ot use boost asio in my program. But when just write "include<boost/asio>" or any other header fie of boost in my program i am getting below errors. It just started all of a suddden before that it was working fine. I am tring it with Eclpse and MinGW.Please also guide me how t setup boost for Visual C++.net 9.0. I have tried boost_1_38_0 and boost_1_41_0 but same problem. i am getting the following errors on eclipse. Thanks in advance, -Asad Description Resource Path Location Type (Errors 5) D:/boost/boost_1_38_0/boost/system/error_code.hpp undefined reference to `boost::system::get_generic_category()' test project 206 C/C++ Problem D:/boost/boost_1_38_0/boost/system/error_code.hpp undefined reference to `boost::system::get_generic_category()' test project 211 C/C++ Problem D:/boost/boost_1_38_0/boost/system/error_code.hpp undefined reference to `boost::system::get_generic_category()' test project 212 C/C++ Problem D:/boost/boost_1_38_0/boost/system/error_code.hpp undefined reference to `boost::system::get_system_category()' test project 205 C/C++ Problem D:/boost/boost_1_38_0/boost/system/error_code.hpp undefined reference to `boost::system::get_system_category()' test project 213 C/C++ Problem (Warnings 9) Description Resource Path Location Type D:/boost/boost_1_38_0/boost/asio/detail/socket_types.hpp #warning Assuming _WIN32_WINNT=0x0501 (i.e. Windows XP target). test project 39 C/C++ Problem D:/boost/boost_1_38_0/boost/asio/detail/socket_types.hpp #warning For example, add -D_WIN32_WINNT=0x0501 to the compiler command line. test project 38 C/C++ Problem D:/boost/boost_1_38_0/boost/asio/detail/socket_types.hpp #warning Please define _WIN32_WINNT or _WIN32_WINDOWS appropriately. test project 37 C/C++ Problem D:/boost/boost_1_38_0/boost/date_time/filetime_functions.hpp left shift count >= width of type test project 101 C/C++ Problem Invalid project path: Include path not found (C:\MinGW\include\c++\4.3.2-dw2). test project pathentry Path Entry Problem Invalid project path: Include path not found (C:\MinGW\include\c++\4.3.2-dw2\backward). test project pathentry Path Entry Problem Invalid project path: Include path not found (C:\MinGW\include\c++\4.3.2-dw2\i686-pc-mingw32). test project pathentry Path Entry Problem Invalid project path: Include path not found (C:\MinGW\lib\gcc\i686-pc-mingw32\4.3.2-dw2\include-fixed). test project pathentry Path Entry Problem Invalid project path: Include path not found (C:\MinGW\lib\gcc\i686-pc-mingw32\4.3.2-dw2\include). test project pathentry Path Entry Problem And on the console it shows like : **** Internal Builder is used for build **** g++ -ID:\boost\boost_1_38_0 -O0 -g3 -Wall -c -fmessage-length=0 -osrc\test project.o ..\src\test project.cpp In file included from D:/boost/boost_1_38_0/boost/asio/detail/win_iocp_io_service_fwd.hpp:24, from D:/boost/boost_1_38_0/boost/asio/io_service.hpp:37, from D:/boost/boost_1_38_0/boost/asio/basic_io_object.hpp:20, from D:/boost/boost_1_38_0/boost/asio/basic_socket.hpp:24, from D:/boost/boost_1_38_0/boost/asio/basic_datagram_socket.hpp:25, from D:/boost/boost_1_38_0/boost/asio.hpp:20, from ..\src\test project.cpp:12: D:/boost/boost_1_38_0/boost/asio/detail/socket_types.hpp:37:5: warning: #warning Please define _WIN32_WINNT or _WIN32_WINDOWS appropriately. D:/boost/boost_1_38_0/boost/asio/detail/socket_types.hpp:38:5: warning: #warning For example, add -D_WIN32_WINNT=0x0501 to the compiler command line. D:/boost/boost_1_38_0/boost/asio/detail/socket_types.hpp:39:5: warning: #warning Assuming _WIN32_WINNT=0x0501 (i.e. Windows XP target). In file included from D:/boost/boost_1_38_0/boost/date_time/microsec_time_clock.hpp:23, from D:/boost/boost_1_38_0/boost/date_time/posix_time/posix_time_types.hpp:11, from D:/boost/boost_1_38_0/boost/asio/detail/select_reactor.hpp:25, from D:/boost/boost_1_38_0/boost/asio/impl/io_service.ipp:27, from D:/boost/boost_1_38_0/boost/asio/io_service.hpp:550, from D:/boost/boost_1_38_0/boost/asio/basic_io_object.hpp:20, from D:/boost/boost_1_38_0/boost/asio/basic_socket.hpp:24, from D:/boost/boost_1_38_0/boost/asio/basic_datagram_socket.hpp:25, from D:/boost/boost_1_38_0/boost/asio.hpp:20, from ..\src\test project.cpp:12: D:/boost/boost_1_38_0/boost/date_time/filetime_functions.hpp: In function `uint64_t boost::date_time::winapi::file_time_to_microseconds(const FileTimeT&)': D:/boost/boost_1_38_0/boost/date_time/filetime_functions.hpp:101: warning: left shift count >= width of type g++ -LC:\boost_1_38_0\libs -LC:\STLport-5.2.0\build\lib -otestproject.exe src\test project.o src\test project.o: In function `Z41__static_initialization_and_destruction_0ii': D:/boost/boost_1_38_0/boost/system/error_code.hpp:205: undefined reference to `boost::system::get_system_category()' D:/boost/boost_1_38_0/boost/system/error_code.hpp:206: undefined reference to `boost::system::get_generic_category()' D:/boost/boost_1_38_0/boost/system/error_code.hpp:211: undefined reference to `boost::system::get_generic_category()' D:/boost/boost_1_38_0/boost/system/error_code.hpp:212: undefined reference to `boost::system::get_generic_category()' D:/boost/boost_1_38_0/boost/system/error_code.hpp:213: undefined reference to `boost::system::get_system_category()' src\test project.o: In function `ZN5boost6detail17sp_counted_impl_pINS_4asio6detail12winsock_initILi2ELi0EE7do_initEE11get_deleterERKSt9type_info': D:/boost/boost_1_38_0/boost/detail/sp_counted_impl.hpp:(.text$_ZN5boost4asio6detail12winsock_initILi2ELi0EE7do_initD1Ev[boost::asio::detail::winsock_init<2, 0>::do_init::~do_init()]+0x7): undefined reference to `WSACleanup@0' D:/boost/boost_1_38_0/boost/detail/sp_counted_impl.hpp:(.text$_ZN5boost4asio6detail12winsock_initILi2ELi0EE7do_initC1Ev[boost::asio::detail::winsock_init<2, 0>::do_init::do_init()]+0x1f): undefined reference to `WSAStartup@8' D:/boost/boost_1_38_0/boost/detail/sp_counted_impl.hpp:(.text$_ZN5boost4asio5error19get_system_categoryEv[boost::asio::error::get_system_category()]+0x7): undefined reference to `boost::system::get_system_category()' collect2: ld returned 1 exit status Build error occurred, build is stopped Time consumed: 4886 ms. -- View this message in context: http://old.nabble.com/getting-errors-whti-boost.-tp26856283p26856283.html Sent from the Boost - Dev mailing list archive at Nabble.com.

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