August 2009 - Boost - lists.boost.org

Checking for return type -- BOOST_STATIC_ASSERT?
by Edward Grace 21 Aug '09

21 Aug '09

I'd like to be able to make certain that a function/functor returns a double precision floating point value. I was always under the impression that it's essentially impossible to check things based on return type. Is there a way to do this? Something like BOOST_STATIC_ASSERT, who knows perhaps that *can* do it.. Ideally I would like to have some sort of compile type warning so that in the following context, class myclass { public: ... template <class O> a_func(O functor) { ASSERT_IS_A_FUNCTOR(O); ASSERT_RETURN_TYPE_CONVERTABLE_TO_FLOAT(O); } }; if O is compatible with the concept of a functor and O returns a type that can be converted to a float, then we are good to go -- otherwise I'd like an intelligible error. If, for example, O is of the type 'void (*)()' I'd like it (the compiler) to spit out, "The function pointer of type O must of signature float (*)()" Any ideas? -ed ------------------------------------------------ "No more boom and bust." -- Dr. J. G. Brown, 1997

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Re: [boost] [interprocess] SHARING_VIOLATION due to antivirus
by raindog＠macrohmasheen.com 21 Aug '09

21 Aug '09

I can confirm that I received your message twice. ------Original Message------ From: Isidor Zeuner Sender: boost-bounces(a)lists.boost.org To: boost(a)lists.boost.org ReplyTo: boost(a)lists.boost.org Sent: Aug 20, 2009 9:21 PM Subject: Re: [boost] [interprocess] SHARING_VIOLATION due to antivirus > Quoting Lars Hagstrom <lars(a)update.uu.se>: > > > Yes, of course it is due to bad AV. But for me it would still be handy > > if boost.interprocess was a little bit more tolerant towards that. If my > > software crashes it will be perceived as buggy, however much I blame AV... > > One thing you can do is to, at startup, detect if nod32.dll is loaded in your > process, and throw up a warning dialog to tell the user that the AV software is > buggy. > This seems inappropriate since, if anything, the operating system kernel which forces user space programmers into busy waiting for obtaining locks could be considered buggy by design in that regard. However, this bug could even be warned about at compile time, so we could solve this in boost itself. It is probably inappropriate to do so by default, but for administrators of heterogenous systems it might become handy to have a preprocessor flag which can warn if someone is about to deploy software which uses features the operating system was not designed for, so it can be considered to move the application to a more appropriate platform. Best regards, Isidor PS: The moderation software of this list seems to be broken. I sent this message before, received a "...was successfully received by the Boost mailing list" acknowledgement after a while, but over 12 hours later the message is still neither "successfully received", nor have I got any new status information. _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost Sent from my Verizon Wireless BlackBerry

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[interprocess] SHARING_VIOLATION due to antivirus
by Lars Hagstrom 21 Aug '09

21 Aug '09

Hi, I've discovered that there is some unfortunate interaction of boost::interprocess and at least one antivirus product (ESET Nod32). The problem manifests on some installations, and the symptom is that an interprocess_exception with a native error code of 32 (ERROR_SHARING_VIOLATION) occurs when a named_semaphore (or other named objects) are opened (well, I've only seen it when opening, but depending on the AV product I guess it may happen when creating as well). Googling a bit on this I found http://support.microsoft.com/kb/316609, which suggests that AV products take exclusive locks on files just as a file is being opened, which sometimes upsets calls to CreateFile. What they suggest is doing retries when a sharing violation occurs. I'm not really saying that this is a boost.interprocess bug, but at least for me it would be handy if it was a little bit more tolerant towards AV products. I've managed (after quite a lot of hard work) to get a test environment where I can reproduce this quite easily, so I'm more than willing to help out with testing. Cheers Lars

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ABI Compliance checker
by Neal Becker 20 Aug '09

20 Aug '09

I wonder if something like this could be added to boost release process to warn of incompatibilities? http://ispras.linux-foundation.org/index.php/ABI_compliance_checker

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[ptr_container] new_clone overload
by Frank Mori Hess 20 Aug '09

20 Aug '09

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I've noticed that ptr_container/clone_allocator.hpp contains an undocumented overload of new_clone that accepts a pointer-to-const: template< class T > inline T* new_clone( const T* r ); It is annoying because it doesn't support a pointer-to-non-const argument, resulting in a compile error if you try. Any chance one of the following could be done? 1) remove it 2) add a pointer-to-non-const overload 3) change it to template< class T > T* new_clone( T* r ); 4) or if you care about always returning a pointer-to-non-const change it to template< class T > typename remove_const<T>::type * new_clone( T* r ); -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkpxsyoACgkQ5vihyNWuA4WnCACgwzxlNxG8z8NAln6Ra8+fNHsn Yr8AoL5a8Bdvkoya1p99GcS1W8N2WSjk =rSZQ -----END PGP SIGNATURE-----

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Review Wizard Status Report for June 2009
by Ronald Garcia 20 Aug '09

20 Aug '09

============================================== Review Wizard Status Report for June 2009 ============================================== News ==== Futures: Williams variant Accepted; Gaskill variant Rejected Boost 1.38 Released New Libraries: Revised Libraries: Boost.Range Extension Accepted Polynomial Library Rejected Boost 1.39 Released Constrained Value Review - Review Result Pending Older Issues ============ The Time Series Library, accepted in August 2007, has not yet been submitted to SVN. Eric Niebler and John Phillips are working on making the changes suggested during the review. The Floating Point Utilities Library, has not yet been submitted to SVN. It is slated to be integrated with the Boost.Math library. The Switch Library, accepted provisionally in January 2008, has not yet been submitted for mini-review and full acceptance. The Phoenix Library, accepted provisionally in September 2008, has not yet been submitted for mini-review and full acceptance. A rewrite of Phoenix, basing it on the Proto metaprogramming library, has just begun. General Announcements ===================== As always, we need experienced review managers. The review queue has been growing substantially but we have had few volunteers, so manage reviews if possible and if not please make sure to watch the review schedule and participate. Please take a look at the list of libraries in need of managers and check out their descriptions. In general review managers are active boost participants or library contributors. If you can serve as review manager for any of them, email Ron Garcia or John Phillips, "garcia at osl dot iu dot edu" and "phillips at mps dot ohio-state dot edu" respectively. We are also suffering from a lack of reviewers. While we all understand time pressures and the need to complete paying work, the strength of Boost is based on the detailed and informed reviews submitted by you. A recent effort is trying to secure at least five people who promise to submit reviews as a precondition to starting the review period. Consider volunteering for this and even taking the time to create the review as early as possible. No rule says you can only work on a review during the review period. A link to this report will be posted to www.boost.org. If you would like us to make any modifications or additions to this report before we do that, please email Ron or John. If you're a library author and plan on submitting a library for review in the next 3-6 months, send Ron or John a short description of your library and we'll add it to the Libraries Under Construction below. We know that there are many libraries that are near completion, but we have hard time keeping track all of them. Please keep us informed about your progress. Review Queue ============ * Lexer * Shifted Pointer * Logging * Log * Join * Pimpl * Thread Pool * Endian * Meta State Machine * Conversion * Sorting * GIL.IO * AutoBuffer * String Convert -------------------- Lexer ----- :Author: Ben Hanson :Review Manager: Eric Neibler :Download: `Boost Vault <http://boost-consulting.com/vault/index.php?action=downloadfile&filename=bo… >`__ :Description: A programmable lexical analyser generator inspired by 'flex'. Like flex, it is programmed by the use of regular expressions and outputs a state machine as a number of DFAs utilising equivalence classes for compression. Shifted Pointer --------------- :Author: Phil Bouchard :Review Manager: Needed :Download: `Boost Vault <http://www.boost-consulting.com/vault/index.php?&direction=0&order=&directo… >`__ :Description: Smart pointers are in general optimized for a specific resource (memory usage, CPU cycles, user friendliness, ...) depending on what the user need to make the most of. The purpose of this smart pointer is mainly to allocate the reference counter (or owner) and the object itself at the same time so that dynamic memory management is simplified thus accelerated and cheaper on the memory map. Logging ------- :Author: John Torjo :Review Manager: Gennadiy Rozental :Download: http://torjo.com/log2/ :Description: Used properly, logging is a very powerful tool. Besides aiding debugging/testing, it can also show you how your application is used. The Boost Logging Library allows just for that, supporting a lot of scenarios, ranging from very simple (dumping all to one destination), to very complex (multiple logs, some enabled/some not, levels, etc). It features a very simple and flexible interface, efficient filtering of messages, thread-safety, formatters and destinations, easy manipulation of logs, finding the best logger/filter classes based on your application's needs, you can define your own macros and much more! Log --- :Author: Andrey Semashev :Review Manager: Needed :Download: `Boost Vault <http://tinyurl.com/cm9lum>`__ :Description: The library is aimed to help adding logging features to applications. It provides out-of-box support for many widely used capabilities, such as formatting and filtering based on attributes, sending logs to a syslog server or to Windows Event Log, or simply storing logs into files. It also provides basic support for the library initialization from a settings file. The library can also be used for a wider range of tasks and implement gathering and processing statistical information or notifying user about application events. Join ---- :Author: Yigong Liu :Review Manager: Needed :Download: http://channel.sourceforge.net/ :Description: Join is an asynchronous, message based C++ concurrency library based on join calculus. It is applicable both to multi-threaded applications and to the orchestration of asynchronous, event-based applications. It follows Comega's design and implementation and builds with Boost facilities. It provides a high level concurrency API with asynchronous methods, synchronous methods, and chords which are "join-patterns" defining the synchronization, asynchrony, and concurrency. Pimpl ----- :Author: Vladimir Batov :Review Manager: Needed :Download: | `Boost Vault <http://www.boost-consulting.com/vault/index.php?action=downloadfile&filenam… >`__ | http://www.ddj.com/cpp/205918714 (documentation) :Description: The Pimpl idiom is a simple yet robust technique to minimize coupling via the separation of interface and implementation and then implementation hiding. This library provides a convenient yet flexible and generic deployment technique for the Pimpl idiom. It's seemingly complete and broadly applicable, yet minimal, simple and pleasant to use. Thread Pool ----------- :Author: Oliver Kowalke :Review Manager: Needed :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=bo… >`__ :Description: The library provides: - thread creation policies: determines the management of worker threads: - fixed set of threads in pool - create workerthreads on demand (depending on context) - let worker threads ime out after certain idle time - channel policies: manages access to queued tasks: - bounded channel with high and low watermark for queuing tasks - unbounded channel with unlimited number of queued tasks - rendezvous syncron hand-over between producer and consumer threads - queueing policy: determines how tasks will be removed from channel: - FIFO - LIFO - priority queue (attribute assigned to task) - smart insertions and extractions (for instance remove oldest task with certain attribute by newst one) - tasks can be chained and lazy submit of taks is also supported (thanks to Braddocks future library). - returns a task object from the submit function. The task it self can be interrupted if its is cooperative (means it has some interruption points in its code -> ``this_thread::interruption_point()`` ). Endian ------ :Author: Beman Dawes :Review Manager: Needed :Download: http://mysite.verizon.net/beman/endian-0.10.zip :Description: Header boost/integer/endian.hpp provides integer-like byte-holder binary types with explicit control over byte order, value type, size, and alignment. Typedefs provide easy-to-use names for common configurations. These types provide portable byte-holders for integer data, independent of particular computer architectures. Use cases almost always involve I/O, either via files or network connections. Although data portability is the primary motivation, these integer byte- holders may also be used to reduce memory use, file size, or network activity since they provide binary integer sizes not otherwise available. Meta State Machine ------------------ :Author: Christophe Henry :Review Manager: Needed :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?direction=0&order=&director… >`__ :Description: Msm is a framework which enables you to build a Finite State Machine in a straightforward, descriptive and easy-to-use manner . It requires minimal effort to generate a working program from an UML state machine diagram. This work was inspired by the state machine described in the book of David Abrahams and Aleksey Gurtovoy "C++ Template Metaprogramming" and adds most of what UML Designers are expecting from an UML State Machine framework: * Entry and Exit Methods * Guard Conditions * Sub state machines (also called composite states in UML) * History * Terminate Pseudo-State * Deferred Events * Orthogonal zones * Explicit entry into sub state machine states * Fork * Entry / Exit pseudo states * Conflicting transitions Conversion ---------- :Author: Vicente Botet :Review Manager: Needed :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=co… >`__ :Description: Generic explicit conversion between unrelated types. Boost.Conversion provides: * a generic ``convert_to`` function which can be specialized by the user to make explicit conversion between unrelated types. * a generic ``assign_to`` function which can be specialized by the user to make explicit assignation between unrelated types. * conversion between ``std::complex`` of explicitly convertible types. * conversion between ``std::pair`` of explicitly convertible types. * conversion between ``boost::optional`` of explicitly convertible types. * conversion between ``boost::rational`` of explicitly convertible types. * conversion between ``boost::interval`` of explicitly convertible types. * conversion between ``boost::chrono::time_point`` and ``boost::ptime``. * conversion between ``boost::chrono::duration`` and ``boost::time_duration``. Sorting ------- :Author: Steven Ross :Review Manager: Needed :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=al… >`__ :Description: A grouping of 3 templated hybrid radix/comparison-based sorting algorithms that provide superior worst-case and average-case performance to std::sort: integer_sort, which sorts fixed-size data types that support a rightshift (default of >>) and a comparison (default of <) operator. float_sort, which sorts standard floating-point numbers by safely casting them to integers. string_sort, which sorts variable-length data types, and is optimized for 8-bit character strings. All 3 algorithms have O(n(k/s + s)) runtime where k is the number of bits in the data type and s is a constant, and limited memory overhead (in the kB for realistic inputs). In testing, integer_sort varies from 35% faster to 8X as fast as std::sort, depending on processor, compiler optimizations, and data distribution. float_sort is roughly 7X as fast as std::sort on x86 processors. string_sort is roughly 2X as fast as std::sort. GIL.IO ------ :Author: Christian Henning :Review Manager: Needed :Download: `GIL Google Code Vault <http://gil-contributions.googlecode.com/files/rc2.zip >`__ :Description: I/O extension for ``boost::gil`` which allows reading and writing of/in various image formats ( tiff, jpeg, png, etc ). This review will also include the Toolbox extension which adds some common functionality to gil, such as new color spaces, algorithms, etc. AutoBuffer ---------- :Author: Thorsten Ottosen :Review Manager: Needed :Download: `Here <http://www.cs.aau.dk/~nesotto/boost/ auto_buffer.zip>`__ :Description: Boost.AutoBuffer provides a container for efficient dynamic, local buffers. Furthermore, the container may be used as an alternative to std::vector, offering greater flexibility and sometimes better performance. String Convert -------------- :Author: Vladimir Batov :Review Manager: Needed :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=bo… >`__ :Description: The library takes the approach of boost::lexical_cast in the area of string-to-type and type-to-string conversions, builds on the past boost::lexical_cast experience and advances that conversion functionality further to additionally provide: * throwing and non-throwing conversion-failure behavior; * support for the default value to be returned when conversion fails; * two types of the conversion-failure check -- basic and better/safe; * formatting support based on the standard I/O Streams and the standard (or user-defined) I/O Stream-based manipulators (like std::hex, std::scientific, etc.); * locale support; * support for boost::range-compliant char and wchar_t-based string containers; * no DefaultConstructibility requirement for the Target type; * consistent framework to uniformly incorporate any type-to-type conversions. It is an essential tool with applications making extensive use of configuration files or having to process/prepare considerable amounts of data in, say, XML, etc. Libraries under development =========================== Please let us know of any libraries you are currently developing that you intend to submit for review. Mirror ------ :Author: Matus Chochlik :Download: | http://svn.boost.org/svn/boost/sandbox/mirror/doc/index.html | `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=mi… >`__ :Description: The aim of the Mirror library is to provide useful meta-data at both compile-time and run-time about common C++ constructs like namespaces, types, typedef-ined types, classes and their base classes and member attributes, instances, etc. and to provide generic interfaces for their introspection. Mirror is designed with the principle of stratification in mind and tries to be as less intrusive as possible. New or existing classes do not need to be designed to directly support Mirror and no Mirror related code is necessary in the class' definition, as far as some general guidelines are followed Most important features of the Mirror library that are currently implemented include: * Namespace-name inspection. * Inspection of the whole scope in which a namespace is defined * Type-name querying, with the support for typedef-ined typenames and typenames of derived types like pointers, references, cv-qualified types, arrays, functions and template names. Names with or without nested-name-specifiers can be queried. * Inspection of the scope in which a type has been defined * Uniform and generic inspection of class' base classes. One can inspect traits of the base classes for example their types, whether they are inherited virtually or not and the access specifier (private, protected, public). * Uniform and generic inspection of class' member attributes. At compile-time the count of class' attributes and their types, storage class specifiers (static, mutable) and some other traits can be queried. At run-time one can uniformly query the names and/or values (when given an instance of the reflected class) of the member attributes and sequentially execute a custom functor on every attribute of a class. * Traversals of a class' (or generally type's) structure with user defined visitors, which are optionally working on an provided instance of the type or just on it's structure without any run-time data. These visitors are guided by Mirror through the structure of the class and optionally provided with contextual information about the current position in the traversal. I'm hoping to have it review ready in the next few months. Interval Template Library ------------------------- :Author: Joachim Faulhaber :Description: The Interval Template Library (Itl) provides intervals and two kinds of interval containers: Interval_sets and interval_maps. Interval_sets and maps can be used just as sets or maps of elements. Yet they are much more space and time efficient when the elements occur in contiguous chunks: intervals. This is obviously the case in many problem domains, particularly in fields that deal with problems related to date and time. Interval containers allow for intersection with interval_sets to work with segmentation. For instance you might want to intersect an interval container with a grid of months and then iterate over those months. Finally interval_maps provide aggregation on associated values, if added intervals overlap with intervals that are stored in the interval_map. This feature is called aggregate on overlap. It is shown by example: :: typedef set<string> guests; interval_map<time, guests> party; guests mary; mary.insert("Mary"); guests harry; harry.insert("Harry"); party += make_pair(interval<time>::rightopen(20:00, 22:00),mary); party += make_pair(interval<time>::rightopen_(21:00, 23:00),harry); // party now contains [20:00, 21:00)->{"Mary"} [21:00, 22:00)->{"Harry","Mary"} //guest sets aggregated on overlap [22:00, 23:00)->{"Harry"} As can be seen from the example an interval_map has both a decompositional behavior (on the time dimension) as well as a accumulative one (on the associated values). StlConstantTimeSize ------------------- :Author: Vicente J. Botet Escriba :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=consta… >`__ :Description: Boost.StlConstantTimeSize Defines a wrapper to the stl container list giving the user the chioice for the complexity of the size function: linear time, constant time or quasi-constant. In future versions the library could include a similar wrapper to slist. InterThreads ------------------- :Author: Vicente J. Botet Escriba :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=in… >`__ :Description: Boost.InterThreads extends Boost.Threads adding some features: * thread decorator: thread_decorator allows to define setup/cleanup functions which will be called only once by thread: setup before the thread function and cleanup at thread exit. * thread specific shared pointer: this is an extension of the thread_specific_ptr providing access to this thread specific context from other threads. As it is shared the stored pointer is a shared_ptr instead of a raw one. * thread keep alive mechanism: this mechanism allows to detect threads that do not prove that they are alive by calling to the keep_alive_point regularly. When a thread is declared dead a user provided function is called, which by default will abort the program. * thread tuple: defines a thread groupe where the number of threads is know statically and the threads are created at construction time. * set_once: a synchonizer that allows to set a variable only once, notifying to the variable value to whatever is waiting for that. * thread_tuple_once: an extension of the boost::thread_tuple which allows to join the thread finishing the first, using for that the set_once synchronizer. * thread_group_once: an extension of the boost::thread_group which allows to join the thread finishing the first, using for that the set_once synchronizer. (thread_decorator and thread_specific_shared_ptr) are based on the original implementation of threadalert written by Roland Schwarz. Boost.InterThreads extends Boost.Threads adding thread setup/cleanup decorator, thread specific shared pointer, thread keep alive mechanism and thread tuples.

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[shifted_ptr] Status
by Phil Bouchard 20 Aug '09

20 Aug '09

Greetings: More than a year ago I have submitted a quite stable version of the shifted_ptr memory manager. I am not aware of the level of understanding of it but I am planning writing more documentation, helping introducing it quicker. For now there is a quick presentation which can be found at: http://svn.boost.org/svn/boost/sandbox/shifted_ptr/libs/smart_ptr/doc/Shift… As far as I am concerned, I stepped into astrophysics and I wrote a book called "Finite Relativism" reengineering the whole relativity theory with standard calculus. This is out of topic for this list but I need writing a complex simulator so I will post on "user". Thank you, -Phil

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building a run-time static version
by Lorenzo Bettini 20 Aug '09

20 Aug '09

Hi I was trying to build a static version of the regex library (boost 1.39), issuing this command: ./bjam --build-dir=build_static --layout=system threading=single runtime-link=static link=static but I always get this error: error: link=shared together with runtime-link=static is not allowed error: such property combination is either impossible error: or too dangerious to be of any use but why is it trying to use link=shared when I explicitly specified link=static? thanks in advance Lorenzo -- Lorenzo Bettini, PhD in Computer Science, DI, Univ. Torino ICQ# lbetto, 16080134 (GNU/Linux User # 158233) HOME: http://www.lorenzobettini.it MUSIC: http://www.purplesucker.com http://www.myspace.com/supertrouperabba BLOGS: http://tronprog.blogspot.com http://longlivemusic.blogspot.com http://www.gnu.org/software/src-highlite http://www.gnu.org/software/gengetopt http://www.gnu.org/software/gengen http://doublecpp.sourceforge.net

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[flat_set/flat_map] request for new constructor that accepts a sorted sequence
by Thorsten Ottosen 20 Aug '09

20 Aug '09

Hi Ion, It would be veyr nice to have the following constructor: template< class Iter > flat_container( Iter, Iter, bool /*tag*/ ); which allows one to give the container an already sorted sequence (this would be the precondition). -Thorsten

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[spirit][karma] In-place modification of previously parsed content?
by Carlos Rafael Giani 19 Aug '09

19 Aug '09

Hello, I wonder if it is possible to modify previously parsed content using Karma. An example is some text like: coordinate (1, 4.15, 1.49, 0.81) // some comment 1 coordinate (1, -19, 4, -1) // some comment 2 Now suppose the numbers are all parsed, and I change the 0.81 to 71.44. I want to update the text accordingly: coordinate (1, 4.15, 1.49, 71.44) // some comment 2 coordinate (1, -19, 4, -1) // some comment 2 Note how the overall formatting and comments are preserved. The text could contain lots of other strings etc. and they would be all left untouched. This part - the preservation - is the hard one, and I ask, is this possible using Karma?

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