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Re: [boost] boost [msm] deferring event by base type
by Christophe Henry 25 Jun '10

25 Jun '10

> I'm now using Row and Defer functor I have now an other problem whit the : > > void defer_event(Event const& e) > { > // to call this function, you need either a state with a > deferred_events typedef > // or that the fsm provides the activate_deferred_events typedef > BOOST_MPL_ASSERT(( has_fsm_deferred_events<library_sm> )); > execute_return (library_sm::*pf) (Event const& evt)= > &library_sm::process_event; > Event temp (e); > ::boost::function<execute_return ()> f= ::boost::bind(pf, this,temp); > post_deferred_event(f); > } > > actually it tries to instantiate the base class ( Event temp (e); ) > but in my case the base class is an abstract class -> compiler error; > and after deferring I want to dispatch the original derived event not > the copy constructed base class instance of the event. What you get is a slicing. The Defer functor works like any action, meaning that the type of the event is encoded in the transition. If you consider a transition: a_row < Stopped , play , Playing , &p::start_playback > and an action: void start_playback(play const&) The type of the event in the action is the one defined in the transition. So what defer_event gets (from Defer) is the type defined in the transition, in your case the base event. It's harder to spot than a vector<base> but about the same. A solution would be to have msm's process_event reinterpret_cast action signature. I will take it into my feature list but probably not at the top as I consider the feature as only nice to have. In the meantime, I, like Juraj, would also suggest you to pimpl your data (with or without a shared_ptr) or define one entry inside deferred_events for every derived event. Regards, Christophe

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boost [msm] deferring event by base type.
by Richard Szabo 25 Jun '10

25 Jun '10

I try to use the following code struct base {}; struct event1 : public base {}; struct MyState1 : public msm::front::state<> { typedef mpl::vector<base> deferred_events; }; than MySm.process_event(event1()); when state machine in MyState1 causes that event gets dispatched and not deferred the same code works if I replace typedef mpl::vector<base> deferred_events; with typedef mpl::vector<event1> deferred_events; than it works fine and event1 is deferred in MyState1; It would be nice to able to defer event by it's base types it would make code maintenance easier not have to declare all events one by one for deferring. Br. Richie

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[filesystem][v3] Class path codecvt argument now available for appropriate functions
by Beman Dawes 24 Jun '10

24 Jun '10

The initial V3 implementation, like V2, could alter the codecvt facet used for conversion via a static imbue() function. This has a number of problems, including: * It is, in effect, a global variable, and thus "considered harmful" as being prone to abuse. * It is subject to data races in multi-threaded environments. * It can be hard to use. * It can be hard to explain. As of revision 63283 this morning, V3 class path in trunk now has an additional "const codecvt&" for all functions where conversion may be required. So you can now write: utf8_codecvt_facet utf8; // UTF-8 facet from boost or other sources path p(some_string, utf8); // some_string will be treated as UTF-8 encoded ... operations on p That's great, but where does that leave path::imbue? I think it should be deprecated. What do others think? --Beman

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[asio] Re: Pass some parameter to io_service::run
by Dmytro Ovdiienko 24 Jun '10

24 Jun '10

James, it is not academic reason. I need latency 1-2us. Right now I have 15us. I cannot waste time on locks and I cannot create bottlenecks. And how about just let user pass "void *"? I know it is not type safe... maybe boost has something like type-safe variable argument list? On 11 January 2010 17:13, James Mansion <james(a)mansionfamily.plus.com>wrote: > Dmytro Ovdiienko wrote: > >> >> I don't understand why you would have an objection to a permanent >> binding with TLS >> >> TLS looks like global variables. Global variables violate encapsulation. I >> suppose to support my program at least 2 years. I don't want to hate myself >> two years :) >> > I think that's quite a silly reason. So are singletons, but they are both > useful. ... > > >> or >> a temporary binding using a pool of parsers, since it seems that >> each datagram must be >> parsed entirely and then the parser reset for the next? >> >> Exactly. But I don't want to create pool of the parsers. Access to the >> pool should be synchronized. Synchronization eats CPU times. >> > ... but not nearly as silly as this one. Getting an item from a pool is a > great candidate for a spinlock and if you're concerned you can easily > segment the pool. Its a non-issue. I defy you to measure it in the context > of all teh context switching and system calls you're doing. > > Of course, the pool is a singleton. And that's like a global. > > The right tools to get you what you want are right there - you're just > choosing not to use them for academic reasons. > > James > > -- Dmytro Ovdiienko e-mail: dmitriy.ovdienko(a)gmail.com skype: dmitriy.ovdienko(a)gmail.com mobile: +38050-1909731 -- Dmytro Ovdiienko e-mail: dmitriy.ovdienko(a)gmail.com skype: dmitriy.ovdienko(a)gmail.com mobile: +38050-1909731

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[thread] once_flag causes dynamic initialization?
by Andrey Semashev 24 Jun '10

24 Jun '10

Hi, I've noticed that on Windows using call_once is not thread-safe as the once_flag structure has a destructor which makes it dynamically initialized. I can see the ticket [1] for this problem is hanging for quite a while, whereas the bug is quite critical, IMHO. Are there any plans on fixing it, perhaps by reverting the change that introduced it? [1] <https://svn.boost.org/trac/boost/ticket/4225> PS: Curiously, the change was made on April, 1st. A long-term joke? :)

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[standard] mutable references
by Gennady Proskurin 24 Jun '10

24 Jun '10

According to 7.1.1-10, reference members cannot be mutable. I think its worth to apply attached patch. ---

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[chrono] Documentation suggestions
by Roland Bock 24 Jun '10

24 Jun '10

Hi, I have a few remarks/suggestions for the documentation of Boost.Chrono: *General: *http://svn.boost.org/svn/boost/sandbox/chrono/libs/chrono/doc/html/index.html There are several sections which attract my attention when trying to get a grip on the library: * Getting Started * Tutorial * Examples Each of those looks a bit like a random collection of valuable hints to me (sorry, if I missed the pattern). My personal troubles in understanding the basics are documented in the mail referenced in the tutorial section. I think it would be worth it to reorganize all three into one section (e.g. tutorial) which shows how to utilize the different parts of the library. For instance with the following subsections: * Clocks (including stopwatch and thread_clock) * Formatters * Reporters * Conversions (see also Tutorial section below) * ...? Each section would contain usage patterns and complete sample programs. *Users Guide: *http://svn.boost.org/svn/boost/sandbox/chrono/libs/chrono/doc/html/boost_chrono/users_guide.html * Personally, I would move the references section to the appendices (I clicked there several times when I really wanted to see the Reference section) *Reference: *http://svn.boost.org/svn/boost/sandbox/chrono/libs/chrono/doc/html/boost_chrono/reference.html * thread_clock is missing in the reference section * typo "chorno.hpp>" on several pages *Examples:* http://svn.boost.org/svn/boost/sandbox/chrono/libs/chrono/doc/html/boost_ch… * There are several hints like "See the file i_dont_like_the_default_duration_behavior.cpp". It would be nice to have a working link to the file instead * Some examples are not linked to a file. I think it would be good to have a working sample file for each example *Tutorial:* http://svn.boost.org/svn/boost/sandbox/chrono/libs/chrono/doc/html/boost_ch… * The section "How to define a thread clock" is now obsolete, isn't it? thread_clock is now integral part of chrono. * An example on how to use the thread_clock would be very helpful. * An example on how to obtain a duration in some unit would be helpful See here (http://lists.boost.org/boost-users/2010/04/58204.php) for what I meant with the last item. The answers by Howard Hinnant in this mail were extremely helpful and could probably be re-used in the tutorial. Regards, Roland

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Re: [boost] [filesystem] wfstream file open does not create file in std::ios_base::out mode
by Ramakrishna, Kirankumar IN BLR SISL 23 Jun '10

23 Jun '10

Hi, I upgraded to boost version 1.43, but that did not help. Still file creation fails with wfstream and error code set is ERROR_FILE_NOT_FOUND. Below code captures the error codes #include "boost/filesystem/fstream.hpp" int main() { boost::filesystem::path pA("C:\\testA.txt"); boost::filesystem::wpath pW(L"C:\\testW.txt"); boost::filesystem::fstream fileHandleA; boost::filesystem::wfstream fileHandleW; fileHandleA.open(pA, std::ios_base::out); cout << "fileHandleA.fail() return value is: " << fileHandleA.fail() << endl; cout << "Error code is: " << GetLastError() << endl; fileHandleW.open(pW, std::ios_base::out); cout << "fileHandleW.fail() return value is: " << fileHandleW.fail() << endl; cout << "Error code is: " << GetLastError() << endl; return 0; } Am I doing something wrong? Regards, Kiran On 2010-06-19 00:44, Beman Dawes wrote: > On Thu, Jun 17, 2010 at 9:48 AM, Ramakrishna, Kirankumar IN BLR SISL > <Kiran.Ramakrishna@???> wrote: > > Hello, > > > > I am using boost version 1.42 and the below code is tested on Windows Xp SP3 and Suse 11.2 > > > > The below code creates new file when opened using fstream object, but fails to create when opened using wftream object. > > This behavior is consistent across platforms (Windows and Linux). > > Also the error code which I get after fileHandleW.open call is, > > > > > > Â 1. Â ERROR_FILE_NOT_FOUND for Â std::ios_base::out > > Â 2. Â ERROR_NEGATIVE_SEEK for std::ios_base::app > > > > In case of append mode, the file gets created. But still I get the above mentioned error code. > > > > Important notice: This e-mail and any attachment there to contains corporate proprietary information. If you have received it by mistake, please notify us immediately by reply e-mail and delete this e-mail and its attachments from your system. Thank You.

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Question about exposing template class to python using boost::python
by Yongning Zhu 23 Jun '10

23 Jun '10

Hi, I implemented a template<class T, int d> VECTOR; Now I can expose specialized class like VECTOR<int,2> to python, but I want to expose more specializations without copying a whole set. What shall I do? I found some early posts about this problem, but didn't figure out a solution. Is class_builder the one I should look for? Thanks in advance? Yong

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Re: [boost] [GIL] kth_channel_view
by fabien.castan＠free.fr 23 Jun '10

23 Jun '10

>> #include <boost/gil/gil_all.hpp> >> ... >> kernel_1d<float> kernel2(gaussian_1,9,4); >> convolve_rows<rgb32f_pixel_t>(kth_channel_view<0>(const_view(img)),kernel2,kth_channel_view<0>(view(img))); >> jpeg_write_view("out-convolution2.jpg", view(img)); >> ... >> >> This doesn't compile. > >Does it compile when using view(img) instead of const_view(img)? >Please provide a complete minimal code sample displaying your problem. >Makes my life easier. ;-) I'm really sorry, I just notice that it's a stupid mistake from me... I forgot to change the template parameter of the concolve_rows function ! If I use k_channel_view I manipulate a grayscale image... kernel_1d<float> kernel2(gaussian_1,9,4); convolve_rows<gray32f_pixel_t>(kth_channel_view<0>(const_view(img)),kernel2,kth_channel_view<0>(view(img))); jpeg_write_view("out-convolution2.jpg", view(img));

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[GIL] kth_channel_view
by fabien.castan＠free.fr 23 Jun '10

23 Jun '10

Hi, I have some difficulties using kth_channel_view. I'm trying to modify the "convolution.cpp" example, like that: #include <boost/gil/gil_all.hpp> ... kernel_1d<float> kernel2(gaussian_1,9,4); convolve_rows<rgb32f_pixel_t>(kth_channel_view<0>(const_view(img)),kernel2,kth_channel_view<0>(view(img))); jpeg_write_view("out-convolution2.jpg", view(img)); ... This doesn't compile. Regards, Fabien

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Re: [boost] [GIL] integration between boost libraries (gil / multiarray)
by fabien.castan＠free.fr 23 Jun '10

23 Jun '10

>> For now view concepts from gil and multi_array are not compatible I >> would say. Hopefully in the future we can agree on 2D and 3D >> container and container view concepts that should be implemented by >> all libs who need such functionality. In the same we way boost needs >> a common point2D structure. ;-) > >I'm not sure why it should be true that we need a common point2D. But >then, maybe I'm missing something. It's not a good thing that some computation functions become dependant to gil only for a point class. To compute a geometric transformation, I cannot directly get a gil point, multiply it by a scalar and return it, because this operator is not define in gil... Or more generally I cannot directly compute a product with an uBlas matrix. Maybe some cast operators and constructors from/to bounded_vector can be suffiscient to have interoperability. >> For example, inside an algorithm I need to maintain a data structure for each pixel. So I would like to create an array of MyCustomStruct. I can use gil to do that but I need to have a notion of colorspace and operators between >> pixels, which have no sense in this particular case. But subsampled_view, cache_locator, etc. have a sense. > >In theory you're right. But both libraries were developed by different >people at different times without having the need to have compatible >concepts. Yes I understand, I discuss possible improvements. I think there is a need to have compatible concepts. >> I have only one criticism: the integration with other boost libraries and firstly with multiarray. >> Because manipulating an image consists of manipulating an array of pixels. Many gil's operations are not present in multiarray: >> flip_view, subsampled_view, subimage_view, n_channel_view, x_iterator, y_iterator, xy_locator, cache_locator, plannar or interleaved arrays, virtual views, static_for_each, ... > >Multi_array is for N-dimensional arrays. GIL only makes sense for 2D >right now. A simple solution can be to implement those gil ideas, which can be applied to N-dimensional, in multi-array to propose the same fonctionnalities ?

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Book "The Boost C++ Libraries" now in English
by Boris Schaeling 23 Jun '10

23 Jun '10

Andreas and I are pleased to announce that the book "The Boost C++ Libraries" is now available in English: <http://en.highscore.de/cpp/boost/> At this point I have to thank Andreas who started translating the 16 chapters of my book nearly a year ago and managed to finish this tremendous amount of work after all that time. Without him there wouldn't be a single sentence of my book available in English. Thank you, Andreas! :-) While you can simply click on <http://en.highscore.de/cpp/boost/> and have a look, here are some explanations in case someone is interested: * The book is licensed under a Creative Commons License and can be copied, distributed and transmitted for non-commercial use. As the part "for non-commercial use" might raise some concerns: You are definitely allowed to use the book at work (print it, hand it out to colleagues, publish it on intranet web servers etc.). We also welcome trainers who want to use the book in classes about the Boost C++ libraries (even if you are paid as a trainer). There is no need to ask us for permission either. What we don't want to see though is e.g. a commercial IT magazine simply filling pages by printing the book. * The book currently consists of 16 chapters. While there are some chapters which present only one library, others introduce a couple of libraries. I decided not to write one chapter per library because some libraries are so small that it's all explained within a few paragraphs. If you want to lookup libraries though you find direct links in the overview at <http://en.highscore.de/cpp/boost/introduction.html#introduction_overview>. * There is a link "Found an error? Fix it in your browser!" below the table of contents in every chapter (your browser must support Javascript to display the link). If you click on the link the webpage becomes editable. This makes it rather easy to fix typos or other mistakes. Changes are saved on the server and will be reviewed (to protect against spam). * If you click on "Found an error? Fix it in your browser!" there is another option called "Mark keywords". If you select this option you can mark words (by clicking on them). The idea is to create an index by marking those words which you think should be included in an index. As it's quite a lot of work to create a good index we welcome proposals of what to include. * For those who know German there is still the original version of the book at <http://www.highscore.de/cpp/boost/>. The content is the very same (even same sample codes). We will also keep the books in sync (it's not that the German version won't be updated anymore). * You can download the HTML version of the book from <http://en.highscore.de/cpp/boost/The%20Boost%20C++%20Libraries.zip>. The ZIP file contains all the web pages and other resources you need to read the book offline. For those who'd like to get a PDF or ePub version of the book there are links to download them. You'll notice that the download of those versions is not for free. The money is used to pay server costs and to finance new chapters. We hope you agree that the prices are reasonable. * If you purchase the ePub version of the book I am very interested in your feedback. As the eBook market is still rather small it's difficult to get the feedback you need to understand what to improve. Given that there have been many discussions lately about what's wrong with Boost, we hope that this book will give the Boost libraries and C++ another, well, boost. :-) Boris

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[chrono] Valgrind complains
by Roland Bock 23 Jun '10

23 Jun '10

Hi Vicente, Valgrind complains about Conditional jump or move depends on uninitialised value(s) several times for the following line: { boost::chrono::stopclock<> stopclock(std::cerr); } Regards, Roland

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Removal request
by Gennaro Prota 22 Jun '10

22 Jun '10

Hi, I've left Boost long ago but I still appear as a maintainer of dynamic_bitset. Could anyone remove me from both Trac and maintainers.txt? Thanks. -- Gennaro Prota | name.surname yahoo.com Do you need expertise in C++? I'm available. __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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[GIL] kth_channel_view
by fabien.castan＠free.fr 22 Jun '10

22 Jun '10

Hi, I have some difficulties using kth_channel_view. I'm trying to modify the "convolution.cpp" example, like that: #include <boost/gil/gil_all.hpp> ... kernel_1d<float> kernel2(gaussian_1,9,4); convolve_rows<rgb32f_pixel_t>(kth_channel_view<0>(const_view(img)),kernel2,kth_channel_view<0>(view(img))); jpeg_write_view("out-convolution2.jpg", view(img)); ... This doesn't compile. Regards, Fabien

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[trac] Milestone 1.43 still open.
by Daniel James 22 Jun '10

22 Jun '10

Hi, Please can someone mark 1.43 as completed in trac? thanks, Daniel

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[gsoc][review/comments] Request community input on project interface
by Brian Bartman 22 Jun '10

22 Jun '10

Hello, I'm currently working on my GSoC project and I wanted some feedback from the community about the interface of a data structure I'm working on called a "bitfield_tuple". The bitfield_tuple makes it easy and simple to create and use specific bitfields. Currently, this works only over integral types, although there are plans to extend this in later versions of the data structure. bitfield_tuples correctly work with different types of endianness as well as provide the mechanisms to allow users to explicitly define the size of the structure's storage space. The bitfield_tuple is a tuple like sequence of elements but, instead of providing direct access to an instance of a type, a proxy to the element stored within the bitfield_tuple is returned. This is similar to std::vector<bool>'s reference type. Example bitfield_tuple declaration, struct red; struct green; struct blue; typedef bitfield_tuple< storage<unsigned int>, member<int,red,5>, member<int,green,6>, member<ing,blue,5> > bft_example; The internal storage type which all of the bitfields are stored in is specified by the storage template. The members are used to specify the different bitfields which are to be stored within that storage type. The member template is specified the exact same way a normal c++ bitfield would be specified inside of a struct or class. int red:5; member<int,red,5> A member template is specified in the order of: type, name, width of bitfield. The order the member templates are given in is the order in which they are stored within the bitfield_tuple. However, the storage template does not take up an index within the bitfield_tuple. So the template member<int,red,5> will be stored at index 0. Each member template requires a name be specified; this is for ease of access, later described in the get function. Each name must be unique within a single bitfield_tuple. The width of the bitfield is handled internally. The starting point for each bitfield is the bit after the previous bitfield, or 0 if it's the first bitfield. bitfield_tuple interface summary: Default constructor, copy constructor, and a constructor which allows for the construction over an initial value which is of the same as the storage type. bitfield_tuple(); bitfield_tuple (bitfield_tuple const&); bitfield_tuple (storage_type); Assignment operators for assignment from the storage type, similar to the constructor above, and copy assignment. bitfield_tuple const& operator=(storage_type); bitfield_tuple const& operator=(bitfield_tuple const&); The get function operates similar to the boost.tuple with slight modification. Specifically, the get function will return a reference type. There are two ways to use the get function. The first way is by using a unsigned integral constant as an index: bft_example temp; temp.get<0>(); // returns a proxy reference to the bitfield represented by member<int,red,5> The second way to use it is to call get using the name provided to the member parameter: temp.get<red>(); // does the same thing as get<0>(); I provide both const and non const versions of both functions. The bitfield_tuple is also a boost.fusion sequence. It models an associative array type by using the following category: struct bft_category : boost::fusion::random_access_ traversal_tag, boost::fusion::associative_tag { }; The btifield_tuple's fusion extension was created through the fusion sequence extension provided by boost.fusion. bitfield_tuple supports the following fusion functions and all of the intrinsic functions which are supported from the implementation of these functions. begin end is_sequence is_view category_of at size at_key tag_of The btifield_tuple_iterator supports the following fusion functions: deref value_of next prior distance key_of value_at_data deref_data advance If you would like to look at the code for bitfield_tuple, it is located here: http://svn.boost.org/svn/boost/sandbox/SOC/2010/bit_masks/boost/integer/bit… -- thanks, Brian Bartman

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Re: [boost] [msm] Message queue and copy constructed events
by Christophe Henry 22 Jun '10

22 Jun '10

Hi Richard, >Lets separate 2 thinks. > >1: no heap operation this is a nice to have feature we can live with >it. According my understanding the only place where heap is used is in >the std:queue ? Am I correct ? If yes than if the user has a >possibility to provide its own queue implementation than he/she can >make sure about avoiding heap usage. In the queue AND in the boost::function objects contained in the queue. So merely changing the container will not be sufficient to eliminate all heap usage (read further on). >2: event copying. You saying copy is happening when bind is used to >anonymize events to be able to store them in a queue. >According my understanding of event driven systems we can say that as >log an RTC step is not finished -> means that the most outer >process_event does not retuned the event which was used in the call of >the process_event should be valid. This means that events will be >valid even with queuing for queues which are used during pseudo entry >and exit because the processing of those events are always finished >before the more outer process_event is returned. >The only place where this is not true ->when the event should be >available longer than the RTC step is when the event is deferred. >So I think it would be enough for non deferred queues to internally >before the bind store the event in a ref/cref and bind that and put >to the queue -> no copy. This is incorrect. You can have the same behaviour with the event queue. Consider test/SimpleWithFunctors.cpp: You have a transition: Row < Empty , cd_detected , Stopped , store_cd_info , ... > And in the action, we generate another event: struct store_cd_info { template <class EVT,class FSM,class SourceState,class TargetState> void operator()(EVT const&,FSM& fsm ,SourceState& ,TargetState& ) { fsm.process_event(play()); // temporary play will be queued, then the function returns // ooops, temporary is gone } /// end of action, transition now ends and will start examining the queue and will find inside a reference to a destroyed event }; Now, if msm was using ref/cref, we would be processing a destroyed event, which would not end well ;-) Unfortunately, it is not possible for process_event to know if the event object is a temporary, therefore the copy. The only way to change this would be to have the user tell msm about it and take responsibility for ensuring event validity. We could: - have an extra parameter to process_event (run-time cost for all users) - allow some compile-time flag (compile-time cost for all users) None is very appealing to me as I doubt many will require this, especially as I fail to see why you could not pimpl the event data, thus making the event cheap to copy. But everybody would have to pay for it somehow. And the heap issue would still be unsolved. This would likely also end at the very bottom of my feature list. I think a possible solution would be the fact that I intend to offer customization of the queue container, which is a much more popular feature. Instead of calling push on it with the boost::function object, I could call push(event), so that you can provide a container not of function objects but of anything (like of a pointers to some base event type or void* if you prefer to cast a little, which I prefer not knowing of ;-) ). This allows complete removal of any heap usage AND could also be used to get rid of event copying (in this case though, you are taking responsibility of having thought of the event objects' lifetime). The downside is that providing a new container will require slightly more work. >For deferred queues there is 2 ways to go. >First is to copy the event during bind or have a user implement a >queue which interacts whit the underlaying zero copy scheduler. and >only again store a ref/cref in a bind. maybe it is enough to have 2 >callback to the user when an event is deferred and when it is recalled >and not needed any more. Fore the deferred queue, I can provide the same mechanism, so that you have have different containers for both if you wish. Using boost.parameter will make these extra template arguments more bearable. Regards, Christophe

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[GIL] integration between boost libraries (gil / multiarray)
by fabien.castan＠free.fr 22 Jun '10

22 Jun '10

Hi, I'm a big fan of gil. It's one of the best library I know. It has really improved my work, which consists of writing image processing algorithms. Thanks to the authors. I have only one criticism: the integration with other boost libraries and firstly with multiarray. Because manipulating an image consists of manipulating an array of pixels. Many gil's operations are not present in multiarray: flip_view, subsampled_view, subimage_view, n_channel_view, x_iterator, y_iterator, xy_locator, cache_locator, plannar or interleaved arrays, virtual views, static_for_each, ... For example, inside an algorithm I need to maintain a data structure for each pixel. So I would like to create an array of MyCustomStruct. I can use gil to do that but I need to have a notion of colorspace and operators between pixels, which have no sense in this particular case. But subsampled_view, cache_locator, etc. have a sense. Another less important thing, I find unfortunate that a structure like "point" is inside gil. Many operators are not defined. Some parts of my code are becoming dependant to gil just for a "point" class, or I need to work with one structure and make a conversion... Is there really nothing in boost for such thing ? Maybe just a typedef on a bounded_vector<2> could be sufficient ? Best regards, Fabien

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[polygon] 1.44 release?
by Simonson, Lucanus J 22 Jun '10

22 Jun '10

I notice that Monday is the deadline for closing the 1.44 release to new libraries. Boost.Polygon is checked into the trunk and more or less passing tests on all the platforms I expect tests to pass. Is there any possibility of making it into the 1.44 release? Thanks, Luke

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Re: [boost] [filesystem] wfstream file open does not create file in
by Ramakrishna, Kirankumar IN BLR SISL 22 Jun '10

22 Jun '10

Hi, I upgraded to boost version 1.43, but that did not help. Still file creation fails with wfstream and error code set is ERROR_FILE_NOT_FOUND. Below code captures the error codes #include "boost/filesystem/fstream.hpp" int main() { boost::filesystem::path pA("C:\\testA.txt"); boost::filesystem::wpath pW(L"C:\\testW.txt"); boost::filesystem::fstream fileHandleA; boost::filesystem::wfstream fileHandleW; fileHandleA.open(pA, std::ios_base::out); cout << "fileHandleA.fail() return value is: " << fileHandleA.fail() << endl; cout << "Error code is: " << GetLastError() << endl; fileHandleW.open(pW, std::ios_base::out); cout << "fileHandleW.fail() return value is: " << fileHandleW.fail() << endl; cout << "Error code is: " << GetLastError() << endl; return 0; } Am I doing something wrong? Regards, Kiran On 2010-06-19 00:44, Beman Dawes wrote: > On Thu, Jun 17, 2010 at 9:48 AM, Ramakrishna, Kirankumar IN BLR SISL > <Kiran.Ramakrishna@???> wrote: > > Hello, > > > > I am using boost version 1.42 and the below code is tested on Windows Xp SP3 and Suse 11.2 > > > > The below code creates new file when opened using fstream object, but fails to create when opened using wftream object. > > This behavior is consistent across platforms (Windows and Linux). > > Also the error code which I get after fileHandleW.open call is, > > > > > > Â 1. Â ERROR_FILE_NOT_FOUND for Â std::ios_base::out > > Â 2. Â ERROR_NEGATIVE_SEEK for std::ios_base::app > > > > In case of append mode, the file gets created. But still I get the above mentioned error code. > > > > Important notice: This e-mail and any attachment there to contains corporate proprietary information. If you have received it by mistake, please notify us immediately by reply e-mail and delete this e-mail and its attachments from your system. Thank You.

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[website] Smaller favicon.ico file
by Jeremiah Willcock 21 Jun '10

21 Jun '10

Our current favicon.ico file (on www.boost.org) is very large (22k), and includes several icons that are too large for the standard 16x16 size for a favicon. Looking at some directions for compressing them, I have created the attached icon which is only 318 bytes and looks almost as good as the current icon. It might be worthwhile to consider replacing the current favicon with this file. It is also available as https://svn.boost.org/htdocs/site/favicon.ico (the favicon for svn.boost.org, but your browser is unlikely to use the new icon if you've downloaded the old one); Dong Inn and I put that in last week as part of some other performance optimizations in Trac. Purging old favicons from Firefox's cache is difficult, though, so you may just want to download it directly and view it in an image viewer. -- Jeremiah Willcock

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Library design Q : overloads v/s default args
by Roshan 21 Jun '10

21 Jun '10

Hope this is not a silly question. The C++ Standard library does not use default arguments. Instead it provides an additional overload. Anybody know why ? For e.g. It provides the following two overloads for accumulate : template<class Itr, class T> accumulate(Itr first, Itr last, T init); template<class Itr, class T, class BinOp> accumulate(Itr first, Itr last, T init, BinOp op); instead of: template<class Itr, class T, class BinOp> accumulate(Itr first, Itr last, T init, BinOp op = std::plus<T>() ); I am wondering if there is any reason to avoid default arguments in general purpose libraries ? - Roshan

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[uuid] Dependency on Boost.MPL & Boost.TypeTraits
by Kedar Bodas 21 Jun '10

21 Jun '10

Hello, The <boost/uuid/uuid.hpp> header currently has a dependency on <boost/mpl/bool.hpp> & <boost/type_traits/is_pod.hpp>. This is only used to declare the type_trait is_pod<uuids::uuid> AFAICT for the uuid_serialize.hpp header. No other part of the library seems to have any dependency on it. Here's my problem: By company policy I am not allowed to make any changes to a boost library header. The MPL & type_traits libraries are not currently authorized for use within our code. This means I can't use Boost.Uuid either. Is it possible for the above included headers to be enclosed within an inclusion guard like UUID_NO_TYPE_TRAITS_DEPENDENCY so that by defining this macro I can remove this dependency without having to change the <boost/uuid/uuid.hpp> header? Or better still since only uuid_serialize.hpp seems to need it this dependency might be moved there. Since we don't use Boost.Serialization in our code this will solve my problem. This will also serve the purpose of reducing the dependencies of the core part of the library and make it more modular. PS. I am not really sure if this belongs in this list or the boost-users mailing list. Thanks, -- Kedar Bodas, Think3 Designs Pvt. Ltd.

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