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Is there any interest in a base class which prevents construction during the static initialization phase?
by Ben Robinson 13 Jun '11

13 Jun '11

Hello, Because the order of static initialization is undefined, numerous difficult to detect problems can arise when multiple objects are initialized during the static initialization phase. This base class would guarantee that a class will never be unintentionally constructed during static initialization. This is the same philosophy behind how boost::noncopyable guarantees that a class will never be unintentionally copied. Usage would appear as follows: #include <submission/nonstaticinitializable.hpp> #include <boost/noncopyable.hpp> namespace { class Foo : private submission::nonstaticinitializable, private boost::noncopyable { public: Foo() : nonstaticinitializable() {} }; // Foo } // unnamed namespace Foo fooThatWillAssert; // This instance asserts during static initialization int main() { nonstaticinitializable::enable_initialization(); // Indicates that static initialization is complete. Foo foo; // This instance initializes successfully after static initialization. return 0; } // main What does Boost think about submission::nonstaticinitializable (I chose the name to mirror noncopyable)? Thank you, Ben Robinson

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Even more Boostcon videos
by Marshall Clow 12 Jun '11

12 Jun '11

Bojan (Thursday): http://blip.tv/boostcon/fast-numerical-computation-in-c-expression-template… Joel (Thursday): http://blip.tv/boostcon/practical-simd-acceleration-with-boost-simd-5261117 Matt (Thursday): http://blip.tv/boostcon/boost-generic-concepts-without-concepts-5262126 I will post a couple more over the weekend, then be on holiday for a couple weeks, then post the rest in early July. -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

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Last of the first batch of Boostcon videos
by Marshall Clow 12 Jun '11

12 Jun '11

Gordon (Thursday): http://blip.tv/boostcon/introducing-mpl-graph-5262812 Bryce (Friday): http://blip.tv/boostcon/ast-construction-with-the-universal-tree-5266608 I am looking into why Bartoz' Haskell preso is not showing up. You can download the mp4 directly here: http://blip.tv/file/get/Boostcon-HaskellThePseudocodeLanguageForCTemplateMe… but the conversion to H.264 seems to time out (I've tried several times) I'll be contacting blip.tv about this in the morning. -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

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[release][phoenix] Permission to merge to release
by Thomas Heller 12 Jun '11

12 Jun '11

Hi, I would like to ask for permission of merging to changesets i commited during the last week to trunk. The risks should be very minimal. The first change fixes a bug with MSVC 7.1 not being able to parse nested function types correctly. Thus it needs some help. The second change is a small fix to allow non-const and const references as function paramaters in bound functions. Both changes fix bugs that were only realised this week. The affected Changesets are: http://svn.boost.org/trac/boost/changeset/72485 and http://svn.boost.org/trac/boost/changeset/72548 I hope these changes get merged to release. Thanks, Thomas

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[phoenix] Bind member functions with non-const reference parameters
by Sergiu Dotenco 12 Jun '11

12 Jun '11

Using phoenix bind with member functions that have non-const reference parameters results in compile errors. However, free functions with similar signature seem to be supported. This behavior is inconsistent, especially compared to existing bind incarnations. For instance: #include <boost/bind.hpp> #include <boost/lambda/bind.hpp> #include <boost/phoenix/phoenix.hpp> void foo(int&) { } struct Foo { void bar(int&) { } }; int main() { using boost::phoenix::placeholders::arg1; int i = 0; Foo f; boost::phoenix::bind(foo, arg1)(i); // works boost::lambda::bind(&Foo::bar, &f, boost::lambda::_1)(i); // works boost::bind(&Foo::bar, &f, _1)(i); // works boost::phoenix::bind(&Foo::bar, &f, arg1)(i); // compile error } Tested with VC10 and boost trunk (r72541).

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[fusion] Serialization support
by Christian Holmquist 12 Jun '11

12 Jun '11

Hey all, Unless I'm mistaken, there's no support for serializing fusion sequences using Boost.Serialization. I had an hour over at work today and hacked together something.. It can be accessed from here: git@github.com:cholmquist/fusion-serialize.git I only tested it on MSVC-2005, didn't write any docs, but if there's interest I could do the additional work.. Unless there's something fundamentally flawed with my implementation.. I do wonder why this hasn't been added previously (?). Cheers, Christian

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Re: [boost] Is Boost interested in the Boost-based Base64 library
by Denis Shevchenko 11 Jun '11

11 Jun '11

2011/6/10 Robert Ramey <ramey(a)rrsd.com> > I think you'd find it interesting to see how the serialization library does > it. > ../boost/archive/iterators/base64_from_binary > ../boost/archive/iterators/binary_from_base64 Yes, Robert. :-) I took theese iterators (and 'transform_width') and wrap them in one simple and ready-to-use solution. Simple and ready-to-use even for novices. I need a such solution, for this common task. And I definetly know many developers looking for such solution. Solution they can use immediately, without long studying the documentation. Just few lines of code: int main() { std::string text = "TEXT"; std::string encoded = boost::base64().encode( text ); std::string text_again = boost::base64().decode< std::string >( encoded ); } You think such (or similar) solution is not needed for Boost? Well, probably it is not needed, but I think it's useful. If not - I apologize for troubling. - Denis

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Fwd: [Boost C++ Libraries] #4922: memory leak in boost::iostreams::detail::chain_impl::~chain_impl()
by Виктор Шугаев 11 Jun '11

11 Jun '11

Hi, more than a half year ago I found memory leak in boost.iostreams library. I wrote a patch and created a ticket (#4922). But it seems that nobody mantains this library. It is critical for my work. -- Thanks in advance, Victor -------- Исходное сообщение -------- Тема: [Boost C++ Libraries] #4922: memory leak in boost::iostreams::detail::chain_impl::~chain_impl() Дата: Thu, 02 Dec 2010 12:25:38 -0000 От: Boost C++ Libraries <noreply(a)lists.boost.org> Копия: boost-bugs(a)lists.boost.org #4922: memory leak in boost::iostreams::detail::chain_impl::~chain_impl() --------------------------------------+------------------------------------- Reporter: victor.shugaev@… | Owner: turkanis Type: Patches | Status: new Milestone: To Be Determined | Component: iostreams Version: Boost 1.45.0 | Severity: Problem Keywords: | --------------------------------------+------------------------------------- It appears that there are some cases when the ''chain_impl::close()'' ('''boost/iostreams/chain.hpp''') throws an exception. If it is invoked from {{{ ~chain_impl() { try { close(); reset(); } catch (...) { } } }}} the following ''reset()'' method won't be invoked and it results in memory leak because of there is a ''delete buf;'' invokation in the ''reset()''. Patch file is attached. Also I have managed to produce such a situation (example is attached). Below shows that the ''gzip_decompressor'' was constructed 4 times (1 time by default constructor and 3 times by copy constructor), but destroyed only 3 times. Destructor for object at 0x4e46b98 wasn't invoked. ---- $ valgrind ./leak_example[[BR]] ==18153== Memcheck, a memory error detector[[BR]] ==18153== Copyright (C) 2002-2009, and GNU GPL'd, by Julian Seward et al.[[BR]] ==18153== Using Valgrind-3.5.0 and LibVEX; rerun with -h for copyright info[[BR]] ==18153== Command: ./leak_example[[BR]] ==18153==[[BR]] '''gzip_decompressor has been constructed at: 0x7ff0007c0[[BR]] gzip_decompressor has been copy constructed from: 0x7ff0007c0 at: 0x7ff000450[[BR]] gzip_decompressor has been copy constructed from: 0x7ff000450 at: 0x7ff000320[[BR]] gzip_decompressor has been copy constructed from: 0x7ff000320 at: 0x4e46b98[[BR]] gzip_decompressor has been destroyed at: 0x7ff000320[[BR]] gzip_decompressor has been destroyed at: 0x7ff000450[[BR]] gzip_decompressor has been destroyed at: 0x7ff0007c0'''[[BR]] ==18153==[[BR]] ==18153== HEAP SUMMARY:[[BR]] ==18153== in use at exit: 51,493 bytes in 13 blocks[[BR]] ==18153== total heap usage: 28 allocs, 15 frees, 69,665 bytes allocated[[BR]] ==18153==[[BR]] ==18153== LEAK SUMMARY:[[BR]] ==18153== '''definitely lost: 216 bytes in 1 blocks'''[[BR]] ==18153== indirectly lost: 51,277 bytes in 12 blocks[[BR]] ==18153== possibly lost: 0 bytes in 0 blocks[[BR]] ==18153== still reachable: 0 bytes in 0 blocks[[BR]] ==18153== suppressed: 0 bytes in 0 blocks[[BR]] ==18153== Rerun with --leak-check=full to see details of leaked memory[[BR]] ==18153==[[BR]] ==18153== For counts of detected and suppressed errors, rerun with: -v[[BR]] ==18153== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 4 from 4)[[BR]] -- Ticket URL:<https://svn.boost.org/trac/boost/ticket/4922> Boost C++ Libraries<http://www.boost.org/> Boost provides free peer-reviewed portable C++ source libraries.

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[thread] Fix compilation with GCC-MinGW64 for 1.47.0?
by Mikko Vainio 11 Jun '11

11 Jun '11

Hi, The trunk version of Boost.Thread compiles with GCC-MinGW64 but the release branch does not[1]. Is the trunk version going to be merged to release for 1.47.0? Cheers, Mikko [1] Here's the error log: gcc.compile.c++ bin.v2/libs/thread/build/gcc-mingw-4.6.1/release/link-static/target-os-windows/threadapi-win32/threading-multi/win32/thread.o "/usr/bin/x86_64-w64-mingw32-g++" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -mthreads -Wno-long-long -DBOOST_ALL_NO_LIB=1 -DBOOST_THREAD_BUILD_LIB=1 -DNDEBUG -I"." -c -o "bin.v2/libs/thread/build/gcc-mingw-4.6.1/release/link-static/target-os-windows/threadapi-win32/threading-multi/win32/thread.o" "libs/thread/src/win32/thread.cpp" In file included from ./boost/thread/win32/basic_timed_mutex.hpp:14:0, from ./boost/thread/win32/mutex.hpp:8, from ./boost/thread/mutex.hpp:14, from ./boost/thread/detail/thread.hpp:13, from ./boost/thread/thread.hpp:22, from libs/thread/src/win32/thread.cpp:10: ./boost/thread/win32/interlocked_read.hpp: In function 'void* boost::detail::interlocked_read_acquire(void* volatile*)': ./boost/thread/win32/interlocked_read.hpp:63:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] ./boost/thread/win32/interlocked_read.hpp: In function 'void boost::detail::interlocked_write_release(void* volatile*, void*)': ./boost/thread/win32/interlocked_read.hpp:71:13: error: cast from 'void*' to 'long int' loses precision [-fpermissive] ./boost/thread/win32/interlocked_read.hpp:71:13: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] In file included from ./boost/thread/win32/mutex.hpp:8:0, from ./boost/thread/mutex.hpp:14, from ./boost/thread/detail/thread.hpp:13, from ./boost/thread/thread.hpp:22, from libs/thread/src/win32/thread.cpp:10: ./boost/thread/win32/basic_timed_mutex.hpp: In member function 'void boost::detail::basic_timed_mutex::destroy()': ./boost/thread/win32/basic_timed_mutex.hpp:46:39: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] In file included from ./boost/thread/win32/mutex.hpp:8:0, from ./boost/thread/mutex.hpp:14, from ./boost/thread/detail/thread.hpp:13, from ./boost/thread/thread.hpp:22, from libs/thread/src/win32/thread.cpp:10: ./boost/thread/win32/basic_timed_mutex.hpp: In member function 'void* boost::detail::basic_timed_mutex::get_event()': ./boost/thread/win32/basic_timed_mutex.hpp:183:43: error: cast from 'void*' to 'long int' loses precision [-fpermissive] ./boost/thread/win32/basic_timed_mutex.hpp:183:43: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] In file included from ./boost/thread/shared_mutex.hpp:14:0, from ./boost/thread/detail/thread_group.hpp:9, from ./boost/thread/thread.hpp:24, from libs/thread/src/win32/thread.cpp:10: ./boost/thread/win32/shared_mutex.hpp: In member function 'T boost::shared_mutex::interlocked_compare_exchange(T*, T, T) [with T = boost::shared_mutex::state_data]': ./boost/thread/win32/shared_mutex.hpp:110:103: instantiated from here ./boost/thread/win32/shared_mutex.hpp:50:99: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] ./boost/thread/win32/shared_mutex.hpp:50:99: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] ./boost/thread/win32/shared_mutex.hpp:51:52: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] ./boost/thread/win32/shared_mutex.hpp:51:52: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] ...failed gcc.compile.c++ bin.v2/libs/thread/build/gcc-mingw-4.6.1/release/link-static/target-os-windows/threadapi-win32/threading-multi/win32/thread.o... ...skipped <pbin.v2/libs/thread/build/gcc-mingw-4.6.1/release/link-static/target-os-windows/threadapi-win32/threading-multi>libboost_thread_win32-mgw46-mt-1_47.a(clean) for lack of <pbin.v2/libs/thread/build/gcc-mingw-4.6.1/release/link-static/target-os-windows/threadapi-win32/threading-multi>win32/thread.o... ...skipped <pbin.v2/libs/thread/build/gcc-mingw-4.6.1/release/link-static/target-os-windows/threadapi-win32/threading-multi>libboost_thread_win32-mgw46-mt-1_47.a for lack of <pbin.v2/libs/thread/build/gcc-mingw-4.6.1/release/link-static/target-os-windows/threadapi-win32/threading-multi>win32/thread.o... ...skipped <pstage/lib>libboost_thread_win32-mgw46-mt-1_47.a for lack of <pbin.v2/libs/thread/build/gcc-mingw-4.6.1/release/link-static/target-os-windows/threadapi-win32/threading-multi>libboost_thread_win32-mgw46-mt-1_47.a... ...failed updating 1 target...

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enable_shared_from_this::weak_from_this() request
by Marat Abrarov 11 Jun '11

11 Jun '11

Hi, boost users and experts. I often use boost::enable_shared_from_this. I know - it contains boost::weak_ptr, which is initiated in the details of boost::shared_ptr's constructor. Also sometimes I need function weak_from_this() at the classes derived from boost::enable_shared_from_this. I currently use something like: ... class my_class : public boost::enable_shared_from_this<my_class> , private boost::noncopyable { ...somewhere in my_class details... private: typedef my_class this_type; typedef boost::weak_ptr<this_type> this_type_weak_ptr; this_type_weak_ptr weak_from_this() { return this_type_weak_ptr(shared_from_this()); } }; // my_class ... But as I know restoring shared_ptr from weak_ptr (done in shared_from_this()) is quite expensive. So my_class::weak_from_this() does unnecessary work instead of just copy internal weak_ptr stored in enable_shared_from_this. So the question is - why there is no weak_from_this() member function in boost::enable_shared_from_this class? May be it would be useful to add such member function? Regards, Marat Abrarov.

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[heap] A few questions
by Andrew Hundt 10 Jun '11

10 Jun '11

I was looking through the Boost.Heap documentation, and I came up with a couple questions: 1) Is it possible to iterate through the heap in order of priority with an iterator? 2) What advantages to the increase() and decrease() functions provide? I also have a few suggestions for improving the documentation: In http://tim.klingt.org/boost_heap/heap/concepts.html the note: boost.heap implements priority queues as max-heaps. While many textbooks and papers are formulated for min-heaps. Using max-heaps is consistent with the STL heap functions, though. would be better written as: boost.heap implements priority queues as max-heaps to be consistent with the STL heap functions. This is in contrast with the typical textbook design, which uses min-heaps. http://tim.klingt.org/boost_heap/heap/data_structures.html Can you provide runtime complexity constraints for each of these data structures? Particularly if the mutable version has different performance from the standard version of each. spelling: For a low arity, the h[e]ight of the heap is larger improved wording: In analogy to d-ary heaps, boost-heaps also provides an mutable version at the cost of an indirection. would be better as: The b_heap_mutable<http://tim.klingt.org/boost_heap/boost/heap/d_ary_heap_mutable.html> class stores the values inside a std::list in order to achieve mutability. You mentioned: | please note, that you *have* to call update before modifying any other node. This should be made more explicit in the documentation Overall this library looks extremely useful. Good work! Cheers! Andrew Hundt

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[Serialization] serialize from and to an already instantiated object.
by nico 10 Jun '11

10 Jun '11

Hello. I've already posted this topic in the boost-user mailing list, but no reply: maybe this boost list is more active... ? Anyway: I use boost.serialization to perform save and load to files. If a class is serializable through the boost mechanism, I'd like to easily add the "savable" feature (through serialization and boost archives). Here how I do, and then I've got 2 questions. I don't post all the #include statements. Let's have a serializable class (I only use text archive for this example) ---------MyClass.h--------- class MyClass { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version); int data_; public: MyClass(); virtual ~MyClass(); }; BOOST_CLASS_EXPORT_KEY(MyClass) ---------MyClass.cpp--------- MyClass::MyClass() : data_(123) {} MyClass::~MyClass() {} template<class Archive> void MyClass::serialize(Archive & ar, const unsigned int version) { ar & data_; } // instanciate the serialize function for text archives #include "boost/archive/text_iarchive.hpp" #include "boost/archive/text_oarchive.hpp" template void MyClass::serialize(boost::archive::text_iarchive & ar, const unsigned int version); template void MyClass::serialize(boost::archive::text_oarchive & ar, const unsigned int version); BOOST_CLASS_EXPORT_IMPLEMENT(MyClass) --------- Now I define a FileSavable class. Its purpose is to add the "save-to-file" feature to a class that can be serialized in a text archive, making the latter inherting from FileSavable, and adding a line in its serialize function, I write it below). ---------FileSavable.h--------- class FileSavable { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version); public: virtual ~FileSavable() {} void SaveToFile(std::string path); void LoadFromFile(std::string path); }; BOOST_CLASS_EXPORT_KEY(FileSavable) ---------FileSavable.cpp--------- template<class Archive> void FileSavable::serialize(Archive & ar, const unsigned int version) {} void FileSavable::SaveToFile(std::string path) { std::ofstream ofs(path.c_str()); assert(ofs.good()); boost::archive::text_oarchive oa(ofs); oa & this; } void FileSavable::LoadFromFile(std::string path) { std::ifstream ifs(path.c_str()); assert(ifs.good()); boost::archive::text_iarchive ia(ifs); FileSavable* p; ia & p; *this = *p; delete p; } // instanciate the serialize function for text archives #include "boost/archive/text_iarchive.hpp" #include "boost/archive/text_oarchive.hpp" template void FileSavable::serialize(boost::archive::text_iarchive & ar, const unsigned int version); template void FileSavable::serialize(boost::archive::text_oarchive & ar, const unsigned int version); BOOST_CLASS_EXPORT_IMPLEMENT(FileSavable) ---------Modification to MyClass--------- It now inherit from FileSavable: class MyClass : public FileSavable The serialize function call the base class: template<class Archive> void MyClass::serialize(Archive & ar, const unsigned int version) { ar & boost::serialization::base_object<FileSavable>(*this); ar & data_; } --------- Thanks if you read me until here, now my questions: 1) I don't care the FileSavable part of MyClass being serialized, but if I don't call it with boost::serialization::base_object, I have a runtime error: terminate called after throwing an instance of 'boost::archive::archive_exception' what(): unregistered void cast 7MyClass<-11FileSavable Do you see a way to avoid having to add this line in MyClass? Ideally, just having to inheriting from FileSavable would be great: a simple way to add a feature. 2) As you can see, my LoadFromFile function first creates a new MyClass object in p, by de-serializing an archive, and then copies this newly created object into "*this", and finally deletes the object created by the archive d-eserialization. I didn't find a way to avoid this temporary and de-serialize directly in this. Moreover, my solution is not exception-safe, but I didn't manage to de-serialize in a temporary auto_ptr nor boost::shared_ptr. Thanks in advance for replies. Nicolas.

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[multi_array]inner_product interest?
by Larry Evans 10 Jun '11

10 Jun '11

Attached is code to calculate the inner product of 2 multi_arrays. As indicated in comments, the code was adapted from the Budd book. It may be faster than doing subscripting to get the array elements; however, I've done no benchmarks, but I'd guess it would be faster since there's no calls to subscripting operators. Instead, there's just one div call and 3 multiplications per element of the result array. The .txt attachment shows relevant quotes from the book and reasons why changes were made to the book's code to accommodate multi_array's different storage orders. I've not done too much testing, but did do a simple test for 2 by 2 arrays whose output seems correct. Any interest? -regards, Larry

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Re: [boost] Is Boost interested in the Boost-based Base64 library
by Denis Shevchenko 10 Jun '11

10 Jun '11

> Hmmm - so you are proposing that something like the following header > be added to boost? > > ... Yes, Robert, something like this. > a) where in the directory/namespace would this be? boost, boost/utility, or? For example, in boost/base64 directory and in boost namespace. I think it CAN be in boost namespace. So we have boost/base64 directory with docs, examples and base64.hpp file. In main boost directory will be file with same name base64.hpp with: #include <boost/base64/base64.hpp> > c) All this for one small special purpose function? Yes, Robert, for one small, concrete and frequent task. > d) How is a user going to find this pair of functions in the boost libraries. As well as he going to find boost::mem_fn, for example... :-) > e) As soon as someone puts this in, imediately some else will ask - great > but it needs a parameter to so I can change the line width. Then someone > asks for someother tweak. This is the result of making a "simple solution". > It's easy enough to make a simple solution - it's very hard to keep it simple. I understand you. My solution is simple and will be simple. Without "line width", special formatting, etc. Base64 encoding/decoding, nothing else. - Denis

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Re: [boost] Is Boost interested in the Boost-based Base64 library
by Sean Chittenden 09 Jun '11

09 Jun '11

I'm assuming folks have looked at using: > http://code.google.com/p/stringencoders/ Pretty simple API: > char buf[100]; > char result[10]; > char endian[] = {(char)0, (char)0, (char)1}; > int d = modp_b64_encode(buf, endian, 3); And very fast: > http://code.google.com/p/stringencoders/#Why With some neat, very platform specific tricks: > http://code.google.com/p/stringencoders/#How_It_Works Don't get me wrong, I'd definitely like to see Boost have something because that extreme of performance isn't always necessary, but FYI for those interested in the discussion. -sc -- Sean Chittenden sean(a)chittenden.org

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Re: [boost] [Boost-users] More boostcon videos
by Marshall Clow 09 Jun '11

09 Jun '11

On Jun 9, 2011, at 9:05 AM, Ovanes Markarian wrote: > On Thu, Jun 9, 2011 at 5:53 PM, Marshall Clow <mclow.lists(a)gmail.com> wrote: > Bartoz (Tuesday): > http://blip.tv/boostcon/haskell-the-pseudocode-language-for-c-template-meta… > > Tony (Wednesday): > http://blip.tv/boostcon/lockfree-programming-part-2-data-structures-5258064 > > Cliff (Wednesday); > http://blip.tv/boostcon/design-journeys-with-skoot-a-peer-oriented-generic-… > > > I'm hoping to get about half of the videos up before I go on holidays next week. > > Hello Marshall, > > seems like both videos > http://blip.tv/boostcon/lockfree-programming-part-2-data-structures-5258064 > http://blip.tv/boostcon/design-journeys-with-skoot-a-peer-oriented-generic-… > > contain Cliff's presentation. D'oh! I fat-fingered the upload. New link for Tony's preso: http://blip.tv/boostcon/lockfree-programming-part-2-data-structures-5258642 -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

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[Accumulators + Signals2] Compilation error with GCC when both are used
by sguazt 09 Jun '11

09 Jun '11

Hello, It seems that Accumulators and Signals2 have problems to coexist. For instance, look at the following simple C++ program: --- [c++] --- #include <boost/accumulators/accumulators.hpp> #include <boost/accumulators/statistics/stats.hpp> #include <boost/accumulators/statistics/mean.hpp> #include <boost/signals2.hpp> int main() { } --- [/c++] --- If I compile it with GCC 4.6.0 (under Fedora Linux 15 x86_64): $ g++ -Wall -Wextra -pedantic -ansi -I,/boost-trunk -o boost_signals2_accumulators boost_signals2_accumulators.cpp I get the following errors: --- [error] --- In file included from ./boost-trunk/boost/signals2.hpp:20:0, from boost_signals2_accumulators.cpp:4: ./boost-trunk/boost/signals2/signal_type.hpp:29:2: error: #error This header requires BOOST_PARAMETER_MAX_ARITY to be defined as 7 or greater prior to including Boost.Parameter headers In file included from ./boost-trunk/boost/signals2.hpp:20:0, from boost_signals2_accumulators.cpp:4: ./boost-trunk/boost/signals2/signal_type.hpp:78:9: error: wrong number of template arguments (6, should be 5) ./boost-trunk/boost/parameter/parameters.hpp:714:8: error: provided for ‘template<class PS0, class PS1, class PS2, class PS3, class PS4> struct boost::parameter::parameters’ ./boost-trunk/boost/signals2/signal_type.hpp:83:9: error: ‘parameter_spec’ is not a class or namespace ./boost-trunk/boost/signals2/signal_type.hpp:83:29: error: expected unqualified-id before ‘<’ token ./boost-trunk/boost/signals2/signal_type.hpp:99:11: error: ‘args’ was not declared in this scope ./boost-trunk/boost/signals2/signal_type.hpp:105:9: error: template argument 1 is invalid ./boost-trunk/boost/signals2/signal_type.hpp:108:31: error: ‘args’ was not declared in this scope ./boost-trunk/boost/signals2/signal_type.hpp:108:67: error: template argument 1 is invalid ./boost-trunk/boost/signals2/signal_type.hpp:111:31: error: ‘args’ was not declared in this scope ./boost-trunk/boost/signals2/signal_type.hpp:111:94: error: template argument 1 is invalid ./boost-trunk/boost/signals2/signal_type.hpp:115:31: error: ‘args’ was not declared in this scope ./boost-trunk/boost/signals2/signal_type.hpp:115:97: error: template argument 1 is invalid ./boost-trunk/boost/signals2/signal_type.hpp:121:13: error: ‘args’ was not declared in this scope ./boost-trunk/boost/signals2/signal_type.hpp:124:11: error: template argument 1 is invalid ./boost-trunk/boost/signals2/signal_type.hpp:128:31: error: ‘args’ was not declared in this scope ./boost-trunk/boost/signals2/signal_type.hpp:128:69: error: template argument 1 is invalid --- [/error] --- I've tried both with last Boost devel version and Boost 1.46.0. Note, I have no problem if one of the two libraries are not used (e.g. if I comment either the first 3 #includes or the last one). Any idea? Thank you very much!! Best, -- Marco

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[config][hp-ux] UTF-8 codecvt_facet.cpp failing on HP-UX
by Beman Dawes 09 Jun '11

09 Jun '11

There is a Filesystem bug report, 5048, that actually affects any library using ...\libs\detail\utf8_codecvt_facet.cpp The problem is line 255: #elif WCHAR_MAX > 0x10000 On HP-UX, WCHAR_MAX is defined like this: # if defined(_INCLUDE_STDCSOURCE_199901) # define WCHAR_MAX UINT_MAX /* max value of an unsigned integer */ # define WCHAR_MIN 0 # else # define WCHAR_MAX (wchar_t)UINT_MAX /* max value of an unsigned integer */ # define WCHAR_MIN (wchar_t)0 # endif An obvious fix is to add #define _INCLUDE_STDCSOURCE_199901 to ...\boost\config\platform\hpux.hpp, and that's been confirmed by the user who originated the bug report. I'm guessing that this fix doesn't work if the user includes <stdint.h> before <boost/config.hpp>, but can't think of anything better. Any objections to committing the change to ...\boost\config\platform\hpux.hpp? --Beman

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[MPL] map size must not be > 19, sunCC vs. gcc
by Bartosz Marcinkiewicz 09 Jun '11

09 Jun '11

Hello, This is on Solaris 11 Express (gcc version 4.3.3, Sun C++ 5.11 SunOS_i386 2010/08/13). When boost::mpl::map<> has more than 19 entries Sun CC does not compile my code. G++ compiles it, even when there are more than 19 entries. [bma@sol11e ~/c++]$ CC -I ~/opt/include -o m3 mpl_map3.cpp && ./m3 "mpl_map3.cpp", line 80: Error: value is not a member of boost::mpl::next<int>. 1 Error(s) detected. [bma@sol11e ~/c++]$ g++ -I ~/opt/include -o m3 mpl_map3.cpp && ./m3 -> 1 -> 2 MPL map size: 20 Both compilers can handle boost::mpl::map with 19 entries. [bma@sol11e ~/c++]$ g++ -I ~/opt/include -o m3 mpl_map3.cpp && ./m3 -> 1 -> 2 MPL map size: 19 [bma@sol11e ~/c++]$ CC -I ~/opt/include -o m3 mpl_map3.cpp && ./m3 -> 1 -> 2 MPL map size: 19 I am attaching code. Is it compiler error in Sun Studio or error in code attached? Thank you for any help. Best regards, bm. -- Bartosz Marcinkiewicz tel. (+48) 516 034 243 e-mail: bma(a)epcon.pl EPCON Sp. z o.o. www.epcon.pl adres: 53-407 Wroclaw, ul. Gajowicka 114/116 tel. (+48) 71 361 75 55 ext. 36 fax (+48) 71 361 74 44

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First Boostcon videos available....
by Marshall Clow 09 Jun '11

09 Jun '11

Keynote: http://blip.tv/boostcon/hans-boehm-threads-and-shared-variables-in-c-0x-key… Chris Kohloff (Monday): http://blip.tv/boostcon/thinking-asynchronously-designing-applications-with… Hartmut (Monday): http://blip.tv/boostcon/phoenix-v3-an-overview-5250984 -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

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More Boostcon videos available
by Marshall Clow 08 Jun '11

08 Jun '11

Sumant (Mondau): http://blip.tv/boostcon/toward-native-xml-processing-using-multi-paradigm-d… Justin (Tuesday): http://blip.tv/boostcon/intel-s-c-software-transactional-memory-compiler-an… Robert Stewart (Tuesday): http://blip.tv/boostcon/spirit-qi-in-the-real-world-5254335 ( I'm not going to be able to keep up this pace, btw...... ) -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

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Re: [boost] First Boostcon videos available....
by Ralf Globisch 08 Jun '11

08 Jun '11

Marschall, thank you so much! It's really cool for those of us who couldn't attend boostcon... >>> Jarrad Waterloo 06/08/11 3:34 PM >>> How do I download the videos? I don't see the download option like past boostcon videos. @Jared, if you use Firefox, there's a plugin called DownloadHelper that you can use to download the videos. On 6/7/2011 8:39 PM, Marshall Clow wrote: > Keynote: http://blip.tv/boostcon/hans-boehm-threads-and-shared-variables-in-c-0x-key… > Chris Kohloff (Monday): http://blip.tv/boostcon/thinking-asynchronously-designing-applications-with… > Hartmut (Monday): http://blip.tv/boostcon/phoenix-v3-an-overview-5250984 > > -- Marshall > > Marshall Clow Idio Software > > A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). > -- Yu Suzuki > > _______________________________________________ > Unsubscribe& other changes: http://lists.boost.org/mailman/listinfo.cgi/boost _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost -- This message is subject to the CSIR's copyright terms and conditions, e-mail legal notice, and implemented Open Document Format (ODF) standard. The full disclaimer details can be found at http://www.csir.co.za/disclaimer.html. This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.

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Re: [boost] First Boostcon videos available....
by Marat Abrarov 08 Jun '11

08 Jun '11

Marshall, > Keynote: http://blip.tv/boostcon/hans-boehm-threads-and-shared-variables-in-c-0x-key… > Chris Kohloff (Monday): http://blip.tv/boostcon/thinking-asynchronously-designing-applications-with- > boost-asio-5250947 > Hartmut (Monday): http://blip.tv/boostcon/phoenix-v3-an-overview-5250984 Long awaited videos! Why not youtube? blip.tv is rather slow (at least in Russia). Regards, Marat Abrarov.

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[Heaps] Compiler error: ‘optional’ was not declared in this scope
by Phil Endecott 08 Jun '11

08 Jun '11

Dear All, I'm trying to do some simple tests with the proposed Heaps library, but I get a mountain of compiler errors that start like this: ./boost_heap-HEAD-449f378/boost/heap/priority_queue.hpp:32: error: ‘optional’ was not declared in this scope ./boost_heap-HEAD-449f378/boost/heap/priority_queue.hpp:32: error: template argument 1 is invalid ./boost_heap-HEAD-449f378/boost/heap/priority_queue.hpp:32: error: expected unqualified-id before ‘,’ token I thought this was probably due to me having a too-old boost installation, but I believe I'm now compiling with 1.46.1 and I get the same error (though I need to verify that my paths are all set correctly). Any ideas anyone? (I've arrived late to this review having been away, but I'd like to do some quick benchmarks if I have time.) Thanks, Phil.

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Re: [boost] Gauging interest in new library re: multiscale/multigranular containers
by nathaniel＠tierblend.org 07 Jun '11

07 Jun '11

Thanks to the two comments (so far). I am happy to provide a more detailed discussion but thought it appropriate to keep my original posting shortish if possible. For a little backstory, although I have been working on code related to my original posting for a while, I decided to formally submit a "gauging interest" after some emails to Barry Smith, the head of the National Center for Ontological Research, who sent me a stack of research papers with new data structures and algorithms relevant to "multiscale" analysis. This gave me a range of functions or algorithms to implement on top of those I was already working on. There's going to be a conference on biomedical ontology in about six weeks' time, so I decided to assign myself the task of completing at least part of a library in preparation for that. NCOR seems to be working on a "partition theory" which takes a top-down approach to scale. I'll base my comments on "A Theory of Granular Partitions": http://ontology.buffalo.edu/smith/articles/partitions.pdf. Partitions are defined as collections of "cells" which can be nested, including one "maximal cell". For lack of a more elegant term, suppose a collection class is called cell_set, as in template<typename CELL_Type> class cell_set; If this class is to model the theory then any instance will need a "maximal cell" or "root" in which all others are contained, which could be autogenerated with a member function. Moreover, it needs a "subcell" relation and an "insert" function which probably would take an existing cell as parent to any new cell and that would default to the root. I think a variation on this class should allow multiply parents, but for now I'll assume along with the above paper that parenthood is unique. The paper also defines a "parthood" relation and "mereological product" such that c * c' represents the set of subcells shared by two cells (which given unique parenthood must be either c or c* or null). They define two notions of summation, one of which simply groups all subcells of c + c' into a set, and another which looks for the least cell actually defined in the partition that contains all of those subcells. I could mention further structures which they define (and which could be member or namespace-scoped functions), but you get the idea. As a practical tool, this construction seems to be used as a kind of sorting machine. In the simplest case, there is one class of "target objects" which are to be fit into the set of cells (they use the term "projection" for a cell "projecting" onto one or more of those objects). So cell_set then takes two type parameters as in template<typename CELL_Type, typename TARGET_Type> class cell_set; the idea being that any cell_set instance would have a "location" function which takes a TARGET_Type value or collection and "locates" it within a cell in cell_set (defaulting to root if nothing else works). Users would have to provide a boolean "fit" function testing whether a TARGET_Type object fits into a CELL_Type object. Scale can be defined on cell_set instances by assigning the largest scale to root and stipulating that subcells are smaller-scaled than parent cells. A default implementation could assign a scale 1 to root, define "depth" as the number of parent cells between a given cell and root, assign scale 0 to the "deepest" cell, and if D is the max depth assign scale to other cells c using 1 - depth(c)/D. More nuanced implementations could consider the number of different subcells which a cell contains, with the idea that cells with more "inner structure" should be assigned larger scale. Scale can also be used to filter cell_sets into more maximal or more minimal calls, providing a kind of granular query machine. Imagine, for example, that a store is building a database for inventory, which fits into a collection of nestable categories. Scalar filtering might come into play if the store wants to temporarily "reassign" products to new categories to prevent categories being listed on their website with too few products, or conversely if the store wants to spotlight categories for some sort of promotion but only ones with no subcategories. Now, personally, I find that parent uniqueness is too restrictive and does not really fit real-world situations (for the same reasons that single inheritance is problematic...). Easing this restriction makes cell_sets more complex in a number of ways. They end up being graphs rather than trees, with parenthood one edge-type among others. I'm not saying that "partition theory" is the last word on multiscale modeling; I think another useful class would be some sort of multi_graph<CELL_Type> which shares many features with cell_set but allows multiple parents and perhaps allows the maximal cell to be undefined. This latter class would be more "bottom up". Instead of introducing new subcells as partitions of existing cells, new cells would be constructed as "mergers" of existing cells. In addition, edge types could be classified based on whether c <> c' (for some link type <>) implies that c is a subcell of c' or that c and c' are both potential subcells of some parent. These differences give rise to different kind of "walks" or constraints on walks, e.g., only follow edges to parents, or to children, or to siblings. Of course, cell_set as I described could be considered a special case of this more general multi_graph structure, but if multi_graph is to inherit cell_set's features it should support the construction of a "sort machine" for one or more target types; that is, provided a user-defined function "fitting" objects "into" vertices in the multi_graph, it should provide location functions for single or collections of objects of the proper type(s). Scalarity and granularity functions would work much as described for cell_sets, although graph-theoretic measures such vertex degree can be used to refine scale quantification for cells. I am particularly interested in using multi_graphs so defined for modeling GUIs. I've read some interesting work by RedWhale software, in Palo Alto, concerning algorithms for matching data elements to UI controls, which they call "interactors". For example, numeric data field would be mapped to spinners, list boxes, edit fields, scrollers, radio buttons, etc., based on their range of allowed values. Assume that the links between data components and interactors are represented by a multigraphs, so that for one edge type <v>, c <v> c' implies that c is a data field and c' is an interactor type which will visually represent c in a GUI. Suppose moreover that c <s> c' implies that c and c' are both interactors but c' is a higher-scales control, such as a notebook or dialog box; and that c <c> c' implies that c and c' are data components with c contained inside c'. The visual clarity of a GUI can be analyzed by studying how these three edge types interact in the graph, and any patterns which emerge could be used to refine algorithms to automatically generate GUIs based on data models. This could be extended by also introducing user-generated-events and application tasks, such as saving updated data to disk, so that c <t> c' could mean that c is a event meaning that the user wants to perform task c' (e.g., save to disk). Finally, to respond to a couple of points raised. For argument's sake, suppose I develop a single cell_graph class which incorporates both the partition and multigraph functionality I've described. (Actually I'd probably want instead to do a small group of related classes rather than one monolith, but, again, this is for argument's sake). Certainly this could be implemented in terms of existing STL containers, but the choice of which container to use is affected by how the cell_graph itself is used. As far as I can tell, for optimal memory usage cell_graph should work on values rather than pointers, but the values should never be copied, if possible, so that pointers into the cell_graph remain valid indefinitely. On the other hand, there are occcasions when it is useful to use cell_graph more as a vector than as a list. I won't go into the precise memory layout I've been using because I have not worked out all the details yet, but I think the choice of something nonstandard is justified. Conversely, even if (say) cell_graph<CELL_Type, PROJECTION_Type> is implemented in terms of standard STL containers behind the scenes, there is enough extra functionality to implement that it makes sense to develop it as a separate library. There are actually several other type parameters which I have not mentioned (although they take defaults), so using "bare" vector or set would yield very unwieldy code; better to hide as much as possible behind typedefs, partial specializations, or inhertiance: template <typename VERTEX_Type, typename CONNECTOR_Type, typename NODE_WRAP_Type, typename NODE_SERVICER_Type> void TierBlend::Route_Matrix_Compiler <VERTEX_Type, CONNECTOR_Type, NODE_WRAP_Type, NODE_SERVICER_Type>::compile(NODE_SERVICER_Type* servicer) ... Stuff like this should be library code, not user code. Finally, there is no single meaning to "scale" or "granularity". A scale metric can be induced on a partition or "partition-graph" based solely on nesting (e.g. subcells inside parent cells) but in real world situations there is no reason why "sibling" cells should have the same scale. The point is merely that classes representing these structures should provide for a scale measure associated with cells, graph vertices, and/or subgraphs, and should be a possible constraint or characterization of edge types as well (e.g. it could be stipulated that c <> c' implies c < c' for edge type <> and parthood relation <). Similarly, "granularity" could be associated with a given filter, query, or operation which specifies a range of scales on which the operation is to be performed. Thanks again for the comments. ---------------------------------------- From: "Edward Diener" <eldiener(a)tropicsoft.com> Sent: Sunday, June 05, 2011 8:18 AM To: boost(a)lists.boost.org Subject: Re: [boost] Gauging interest in new library re: multiscale/multigranular containers On 6/4/2011 4:55 PM, nathaniel(a)tierblend.org wrote: > > Hi: I would like to submit a library which would allow functionality > related to scale and granularity to be performed on STL-like containers. > Until recently I was in a doctoral program specializing in the philosophy > of science, and I am especially interested in multiscale data modeling and > its applications to e.g. GUI design, code generation, decision procedures, > and DSL implementation. For example, one of my projects involves a DSL > implemented through multiscale graphs in lieu of conventional syntax trees. > I used to study at Buffalo, which houses the National Center for > Ontological Research -- headed by the quite broad-ranging scholar Barry > Smith -- and has done pioneering work in biomedical ontology and also in > ontological models related to complex or "vague" aggregative structures. > In these structures collections of objects of some base type T can be > defined as aggregates but with varying degrees of looseness or "individual > coherence"; and this aggregation can be iterated to produce multiscaled > structures which can be queried or represented at different granularities. > There are a number of analytic procedures which can be implemented on such > structures, some overlapping with graph theoretic or statistical methods. > These structures also possess alot of internal structure above and beyond > their underlying list of values, so they are suited to memory-optimized C++ > code rather than higher-level languages like Java. However, I am not aware > of generic libraries which really incorporate these kind of data structures > and their analysis in a systematic way, although I have come across > non-template libraries which implement some similar features. What I > propose is a library which could be used in a fashion similar to > std::vector or std::set but which support additional functions along the > lines of, e.g., building multigraphs out of T-type nodes; partitions of > T-sets with functions to define or measure e.g. intrapartition relevance; > defining (or extending) a scale metric on T-objects, T-sets, T-arrays, or > other "T- data structures" and using it for rescaling, scale-filter, and > other scale-related transformations; defining iterators or "walks" on > T-collections which take scale and granularity into account; etc. In a > number of cases the algorithms for these kinds of operations have been > described in theoretical form or even already implemented in languages like > Scheme. You generally need to define "scale" and "granularity" in mathematical terms for computer programmers, else you are just interesting scientists in our particular area. Also would it not be possible to create a class which consists of an STL container and some other objects which represent "scale" and "granularity" and add the necessary functionality to that class rather than attempting to re-engineer some STL container ? _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

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