January 2012 - Boost-announce - lists.preview.boost.org

[boost] [context] Boost.Context library accepted
by Giovanni Piero Deretta 29 Jan '12

29 Jan '12

Hi All, The mini-review of the boost.context library from Oliver Kowalke ended two weeks ago. After a slow start, three reviews were eventually submitted, all positive. For a mini-review, I think this is enough and, as the review manager, I'm happy to announce that Boost.Context is accepted as an official boost library. Congratulations to Oliver for this achievement and thanks for submitting an useful library to Boost. Most of the review discussions were around the quality of the documentation and some misunderstanding of some details of the library. While the documentation has greatly improved since the first review, I think that it can be still improved. I encourage Oliver to seek the help of some native English speaker to help copy edit the docs. Finally I would like to thanks everybody that participated in the review discussions and in particular those that submitted reviews. regards, -- Giovanni Deretta, _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

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[1.49.0] Beta 1 available
by Beman Dawes 28 Jan '12

28 Jan '12

Boost release 1.49.0 beta 1 is now available from SourceForge See http://sourceforge.net/projects/boost/files/ This release contains a new library, Boost.Heap priority queues, and numerous enhancements and bug fixes for existing libraries. For details of what's in the release, see http://beta.boost.org/users/news/version_1_49_0. Note that the links to files on this web page are for the final release - use the SourceForge link above to get the beta files. Please download the beta, give it a try, and report any problems you encounter. Thanks, -- The Boost Release Team

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Vote Boost Up for SourceForge Project of the Month
by Dave Abrahams 19 Jan '12

19 Jan '12

Folks, I was just informed that Boost is a top contender for SourceForge's February Project Of The Month. The vote is happening on TwtPoll, here: http://twtpoll.com/7vt4lq It's pretty close, so if you could vote Boost up, it could be good for our profile and our future. Thanks! -- Dave Abrahams BoostPro Computing http://www.boostpro.com

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[C++ Now! 2012] Deadline extension: Call for Submissions, new deadline is January 20th, 2012
by Hartmut Kaiser 10 Jan '12

10 Jan '12

INAUGURAL C++ NOW! CONFERENCE 2012 Aspen CO, USA, May 14-18, 2012, www.cppnow.org CALL FOR SUBMISSIONS We invite you to submit session proposals to the Inaugural C++ Now! Conference: C++Now! 2012 (Aspen CO, USA, May 14 - 18, 2012). Based on the successful traditions of 5 years of BoostCon, which was the main face-to-face event for all things C++ and Boost (www.boost.org) C++Now! 2012 will present leading speakers from the whole C++ community. The conference name is changing to C++ Now! to reflect the current value of the language, the focus on its new state (from the new Standard), and the need to continually look to the future so the language remains useful to the C++ community. The focus of this conference will be the new C++11 language Standard and as usual Boost: what's new in C++, its Standard library, and in the Boost libraries, how to write and maintain them, how to evangelize or to deploy Boost within your organization. The new C++ Standard, but also the infrastructure and process of Boost, its vision and mission - no matter what you are interested in, it all comes together in the C++Now! sessions. Meet the colleagues, and feel the inspiration to support your work with C++ and Boost for the next year. The C++ Now! Conference is dedicated to discussion and education about C++, an open and free language and standard. Our Conference will focus on discussion and education about open source software usage and developments in the C++ developer and user community. To reflect the breadth of the C++ and Boost communities, the conference includes sessions aimed at three constituencies: C++ and Boost end-users, hard-core Boost library and tool developers, and researchers pushing the boundaries of computation. The program fosters interaction and engagement within and across those groups, with an emphasis on hands-on, participatory sessions. As a multi-paradigm language, C++ is a melting pot where the most compelling ideas from other programming communities are blended in powerful ways. Historically, some of the most popular sessions at C++Now! have highlighted these concepts, from DSLs to functional programming to transactional memory and more. Bring your C#, Python, Ruby or Haskell influences to bear in an environment that will broaden their exposure. IMPORTANT DATES New proposal submissions due: January 20th, 2012. UPDATED! Proposals decisions sent (tentative program): February 17th, 2012. Fully scheduled program available: February 25th, 2012. Session materials due: April 15th, 2012. BEST PRESENTATION AWARDS We know how much effort it takes to prepare talks for our conference. For this reason we will award the best presentations in the following categories: Best Presentation, Best Short Presentation, Best Tutorial, and Best Workshop. The awards will be given based on the audience's voting. Each award will include the author's name listed on the cover of the C++Now! website for that year and a plaque containing all the C++Now! conference information. SESSION TOPICS Topics of interest include, but are not restricted to, the following: * C++11 and how it changes life for users and library writers * General tutorial sessions on C++11, the C++11 Standardslibrary, and one or more Boost libraries * In-depth sessions on using specific Boost libraries * Case studies on using Boost * Experts panels * Advanced sessions on implementation techniques used within Boost libraries * Development workshops to extend or enhance existing Boost libraries * Workshops on design process * Infrastructure workshops such as Build tools, Website, Testing * Concepts and Generic Programming * Hardware and infrastructure presentations focused on how libraries can make better use of the technology * Software development tools and their application to C++ and or Boost * Other topics likely to be of great interest to Boost users and developers Interactive and collaborative sessions are encouraged, as this is the style of learning and participation that has proven most successful at such events. Sessions can be tutorial based, with an emphasis on interaction and participant involvement, or workshop based, whether hands-on programming or paper-based, discussion-driven collaborative work. SESSION FORMATS Presentations Presentations focus on a practitioner's ideas and experience with anything relevant to C++11, Boost and users. Panels Panels feature three or four people presenting their ideas and experiences relating to C++11 and Boost's relevant, controversial, emerging, or unresolved issues. Panels may be conducted in several ways, such as comparative, analytic, or historic. Tutorials Tutorials are sessions at which instructors teach conference participants specific skills relevant to C++11 and Boost. Workshops Workshops provide an active arena for advancements In Boost-relevant topics. Workshops provide the opportunity for experienced practitioners to develop new ideas about a topic of common interest and experience. Author's Corner These were introduced at BoostCon 2008, and were a great Presentations success They are short (30 minute) sessions, focusing on tips on usage and design. In addition, we're looking to uncover the hidden design gems in Boost libraries. Tool Vendors We actively encourage tool vendors and ISP's to submit presentations proposals for a special Tool Vendors Session Track aimed at products related to Boost and C++ (compilers, libraries, tools, etc.). Other formats may also be of interest. Don't hold back a proposal just because it doesn't fit into a pigeonhole. SUBMITTING A PROPOSAL Standard Sessions are 60 minutes. You may submit a proposal for fractions or multiples of 90-minutes. Fractional proposals will be grouped into 60 minute sessions covering related topics. Longer sessions, such as tutorials and classes, will be assigned 90 minute, three hour (i.e. half day), or six hour (i.e. full day) time slots. Please include: * The working title. * Type of session: presentation, panel, tutorial, workshop, authors corner, vendor track, other. * A paragraph or two describing the topic covered, suitable for the conference web site. * Proposed length: 10-20 minute short talks, 45 minutes, 90 minutes, half day, full day. * Alternate lengths, if you are willing to make adjustments: 10- 20 minute short-talks, 45 minutes, 90 minutes, half-day, full day. * Audience: users, developers, both. * Level: basic, intermediate, advanced. * A biography, suitable for the conference web site. * Your contact information (will not be made public). SUBMISSION DETAILS All submissions should be made through the EasyChair conference management system: http://www.easychair.org/conferences/?conf=cppnow2012. If you have not already registered at EasyChair, you will need to do so in order to submit your proposal. All submissions will go through a peer review process. Authors are invited (but are not required) to submit PDF versions of full papers of up to 10 pages in ACM conference proceedings format (see http://www.acm.org/sigs/publications/proceedings-templates) The full papers are not required unless you want them published in the proceedings. All accepted proposals will be made available in the Association for Computing Machinery (ACM) Digital Library (approval pending). Best papers, after further reviews, will be considered to be book chapters or journal articles in a renowned journal. The session materials go on the C++Now! website and will be available to attendees. For general information on the C++Now! 2012 paper submission or the scope of technical papers solicited, please refer to the conference website at www.cppnow.org. For any other questions about the submission process or paper format, please contact the Program Committee at cppnow2012(a)easychair.com. If you have any technical problems with EasyChair, please contact EasyChair for help. Note: Presenters must agree to grant a non-exclusive perpetual license to publish submitted materials, either electronically or in print, in any media related to C++ Now!. Hartmut Kaiser, email: hartmut.kaiser(a)gmail.com (Program Committee Chair) Dave Abrahams, email: dave(a)boostpro.com (Conference Chair) On behalf of the conference organizers

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Boost Review Wizard Report for January 2012
by Ronald Garcia 10 Jan '12

10 Jan '12

============================================== Review Wizard Status Report for January 2012 ============================================== News ==== 1. Type Traits Library Extensions Accepted 2. AutoIndex Tool Accepted 3. Heaps Library Accepted 4. Assign v2 Library Rejected 5. Type Traits Introspection Library Accepted 6. Lockfree Library Accepted 7. Algorithm Library Accepted 8. Atomic Library Accepted 9. Local Library Accepted 10. Context Mini-review Ongoing Open Issues =========== The following libraries have been reviewed and await reports from their review managers: * Conversion - reviewed August 2011; review manager: Gordon Woodhull. The following libraries have been accepted to Boost, but have not yet been submitted to SVN: * Constrained Value - accepted September 2010; author: Robert Kawulak * GIL.IO - accepted January 2011; author: Christian Henning. * Atomic - accepted July 2011; author Helge Bahmann * Lockfree - accepted August 2011; author: Tim Blechmann. * Algorithm - accepted December 2011; author: Marshall Clow The following libraries have been accepted and submitted to SVN, but have not yet appeared in a release: * Heaps - accepted June 2011; author: Tim Blechmann. * Type Traits Introspection - accepted August 2011; author: Edward Diener. The following libraries have been accepted provisionally to Boost, but have not been submitted for mini-review and full acceptance: * Log - accepted provisionally March 2010; author: Andrey Semashev. * Endian - accepted provisionally November 2011; author: Beman Dawes. After repeated failed attempts to contact the author, the following library has been marked as Orphaned. * Switch library, accepted provisionally January 2008 author: Steven Watanabe. General Announcements ===================== As always, we need experienced review managers. 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, including library contributors, infrastructure contributors, and other mailing list participants with a substantial track record of constructive participation. If you can serve as review manager for any of them, email Ron Garcia or John Phillips, "rxg at cs dot cmu dot edu" and "phillips at pacific dot 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. If you are interested in reviewing a library but won't have time during the review period, you can always prepare your review ahead of time. 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. The review schedule is an unordered list of the libraries awaiting review. As such, any library on the schedule can be reviewed once the developer is ready, a review manager has been secured, and the manager, developer, and wizards agree on a date to schedule the review. Review Schedule =============== * Join (M) * Pimpl (M) * Sorting (M) * Quaternions, Vectors, Matrices (M) * Variadic Macro Data (M) * Block Pointer (M) * Network (M) * Singularity (M) * Predef (M) ``(M)`` marks libraries that need review managers. -------------------- 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&fil…>`__ | 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. 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 2X as fast as std::sort, depending on processor, compiler optimizations, and data distribution. float_sort is roughly 70% faster than std::sort. string_sort is roughly 2X as fast as std::sort. Quaternions, Vectors, Matrices ------------------------------ :Author: Emil Dotchevski :Review Manager: Needed :Download: http://www.revergestudios.com/boost-qvm/ :Description: QVM defines a set of generic functions and operator overloads for working with quaternions, vectors and matrices of static size. The library also defines vector and matrix data types, however it allows users to introduce their own types by specializing the q_traits, v_traits and m_traits templates. Variadic Macro Data ------------------- :Author: Edward Diener :Review Manager: Needed :Download: `Boost Sandbox <http://svn.boost.org/svn/boost/sandbox/variadic_macro_data/>`__ :Description: The variadic_macro_data library adds support and functionality for variadic macros to Boost as well as integrating variadic macros with the Boost PP library without changing the latter library in any way. Block Pointer ------------- :Author: Phil Bouchard :Review Manager: Needed :Download: `Boost Sandbox <https://svn.boost.org/svn/boost/sandbox/block_ptr/>`__ :Description: Deterministic memory manager of constant complexity capable of handling cyclic collections. Network ------- :Author: Dean Michael Berris :Review Manager: Needed :Download: http://cplusplus-soup.com/2011/04/18/cpp-netlib-0-9-0-released/ :Description: This is a library that provides application layer protocol support using modern C++ techniques. It is light-weight, fast, cross-platform and is intended to be as easy to configure as possible. Singularity ----------- :Author: Ben Robinson :Review Manager: Needed :Download: https://github.com/icaretaker/Singularity :Description: The Singularity Design Pattern allows you to restrict any class to a single instance. Unlike the infamous Singleton, Singularity gives you direct control over the lifetime of the object, does not require you to grant global access to the object, nor does it limit you to the default constructor for that object. Predef ------ :Author: Rene Rivera :Review Manager: Needed :Download: http://tinyurl.com/73n6a3k :Description: The Predef library implements two simple tasks: 1. Definition of a single version number macro to provide consistent version number at the preprocessor level. 2. A collection of detected definitions for compilers, standard libraries, architectures, operating systems, and languages. Unlike the Boost Config Library it doesn't define language features and capabilities. But only defines presence of detected compilation context. Documentation and downloads are available in the sandbox.. Libraries under development =========================== See http://svn.boost.org/trac/boost/wiki/LibrariesUnderConstruction for a current listing of libraries under development.

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[C++ Now! 2012] Reminder: Call for Submissions, deadline is January 10th, 2012
by Hartmut Kaiser 03 Jan '12

03 Jan '12

INAUGURAL C++ NOW! CONFERENCE 2012 Aspen CO, USA, May 14-18, 2012, www.cppnow.org CALL FOR SUBMISSIONS We invite you to submit session proposals to the Inaugural C++ Now! Conference: C++Now! 2012 (Aspen CO, USA, May 14 - 18, 2012). Based on the successful traditions of 5 years of BoostCon, which was the main face-to-face event for all things C++ and Boost (www.boost.org) C++Now! 2012 will present leading speakers from the whole C++ community. The conference name is changing to C++ Now! to reflect the current value of the language, the focus on its new state (from the new Standard), and the need to continually look to the future so the language remains useful to the C++ community. The focus of this conference will be the new C++11 language Standard and as usual Boost: what's new in C++, its Standard library, and in the Boost libraries, how to write and maintain them, how to evangelize or to deploy Boost within your organization. The new C++ Standard, but also the infrastructure and process of Boost, its vision and mission - no matter what you are interested in, it all comes together in the C++Now! sessions. Meet the colleagues, and feel the inspiration to support your work with C++ and Boost for the next year. The C++ Now! Conference is dedicated to discussion and education about C++, an open and free language and standard. Our Conference will focus on discussion and education about open source software usage and developments in the C++ developer and user community. To reflect the breadth of the C++ and Boost communities, the conference includes sessions aimed at three constituencies: C++ and Boost end-users, hard-core Boost library and tool developers, and researchers pushing the boundaries of computation. The program fosters interaction and engagement within and across those groups, with an emphasis on hands-on, participatory sessions. As a multi-paradigm language, C++ is a melting pot where the most compelling ideas from other programming communities are blended in powerful ways. Historically, some of the most popular sessions at C++Now! have highlighted these concepts, from DSLs to functional programming to transactional memory and more. Bring your C#, Python, Ruby or Haskell influences to bear in an environment that will broaden their exposure. IMPORTANT DATES New proposal submissions due: January 10th, 2012. Proposals decisions sent (tentative program): February 17th, 2012. Fully scheduled program available: February 25th, 2012. Session materials due: April 15th, 2012. BEST PRESENTATION AWARDS We know how much effort it takes to prepare talks for our conference. For this reason we will award the best presentations in the following categories: Best Presentation, Best Short Presentation, Best Tutorial, and Best Workshop. The awards will be given based on the audience's voting. Each award will include the author's name listed on the cover of the C++Now! website for that year and a plaque containing all the C++Now! conference information. SESSION TOPICS Topics of interest include, but are not restricted to, the following: * C++11 and how it changes life for users and library writers * General tutorial sessions on C++11, the C++11 Standardslibrary, and one or more Boost libraries * In-depth sessions on using specific Boost libraries * Case studies on using Boost * Experts panels * Advanced sessions on implementation techniques used within Boost libraries * Development workshops to extend or enhance existing Boost libraries * Workshops on design process * Infrastructure workshops such as Build tools, Website, Testing * Concepts and Generic Programming * Hardware and infrastructure presentations focused on how libraries can make better use of the technology * Software development tools and their application to C++ and or Boost * Other topics likely to be of great interest to Boost users and developers Interactive and collaborative sessions are encouraged, as this is the style of learning and participation that has proven most successful at such events. Sessions can be tutorial based, with an emphasis on interaction and participant involvement, or workshop based, whether hands-on programming or paper-based, discussion-driven collaborative work. SESSION FORMATS Presentations Presentations focus on a practitioner's ideas and experience with anything relevant to C++11, Boost and users. Panels Panels feature three or four people presenting their ideas and experiences relating to C++11 and Boost's relevant, controversial, emerging, or unresolved issues. Panels may be conducted in several ways, such as comparative, analytic, or historic. Tutorials Tutorials are sessions at which instructors teach conference participants specific skills relevant to C++11 and Boost. Workshops Workshops provide an active arena for advancements In Boost-relevant topics. Workshops provide the opportunity for experienced practitioners to develop new ideas about a topic of common interest and experience. Author's Corner These were introduced at BoostCon 2008, and were a great Presentations success They are short (30 minute) sessions, focusing on tips on usage and design. In addition, we're looking to uncover the hidden design gems in Boost libraries. Tool Vendors We actively encourage tool vendors and ISP's to submit presentations proposals for a special Tool Vendors Session Track aimed at products related to Boost and C++ (compilers, libraries, tools, etc.). Other formats may also be of interest. Don't hold back a proposal just because it doesn't fit into a pigeonhole. SUBMITTING A PROPOSAL Standard Sessions are 60 minutes. You may submit a proposal for fractions or multiples of 90-minutes. Fractional proposals will be grouped into 60 minute sessions covering related topics. Longer sessions, such as tutorials and classes, will be assigned 90 minute, three hour (i.e. half day), or six hour (i.e. full day) time slots. Please include: * The working title. * Type of session: presentation, panel, tutorial, workshop, authors corner, vendor track, other. * A paragraph or two describing the topic covered, suitable for the conference web site. * Proposed length: 10-20 minute short talks, 45 minutes, 90 minutes, half day, full day. * Alternate lengths, if you are willing to make adjustments: 10- 20 minute short-talks, 45 minutes, 90 minutes, half-day, full day. * Audience: users, developers, both. * Level: basic, intermediate, advanced. * A biography, suitable for the conference web site. * Your contact information (will not be made public). SUBMISSION DETAILS All submissions should be made through the EasyChair conference management system: http://www.easychair.org/conferences/?conf=cppnow2012. If you have not already registered at EasyChair, you will need to do so in order to submit your proposal. All submissions will go through a peer review process. Authors are invited (but are not required) to submit PDF versions of full papers of up to 10 pages in ACM conference proceedings format (see http://www.acm.org/sigs/publications/proceedings-templates) The full papers are not required unless you want them published in the proceedings. All accepted proposals will be made available in the Association for Computing Machinery (ACM) Digital Library (approval pending). Best papers, after further reviews, will be considered to be book chapters or journal articles in a renowned journal. The session materials go on the C++Now! website and will be available to attendees. For general information on the C++Now! 2012 paper submission or the scope of technical papers solicited, please refer to the conference website at www.cppnow.org. For any other questions about the submission process or paper format, please contact the Program Committee at cppnow2012(a)easychair.com. If you have any technical problems with EasyChair, please contact EasyChair for help. Note: Presenters must agree to grant a non-exclusive perpetual license to publish submitted materials, either electronically or in print, in any media related to C++ Now!. Hartmut Kaiser, email: hartmut.kaiser(a)gmail.com (Program Committee Chair) Dave Abrahams, email: dave(a)boostpro.com (Conference Chair) On behalf of the conference organizers

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[boost] [review] Boost.Context mini-review starts today, January 2nd
by Giovanni Piero Deretta 02 Jan '12

02 Jan '12

Hi all, we will start a new year of Boost reviews with a one week mini-review of the Boost.Context library of Oliver Kowalke. The review period starts today January 2nd and ends January 11. Please use [context review] as prefix of your post. Reviewers are strongly encouraged to send their reviews to the boost development mailing list as this is the I follow more assiduously. Please note that Boost.Context was already reviewed and conditionally accepted last May, so we are not voting for acceptance. Instead, this mini-review is to discuss whether the library meets the conditions on acceptance that were listed by Vicente Botet, the review manager at that time. You'll find the whole list at the end of this email. Since the end of the original review, Oliver has spent a large amount of time on a partial rewrite of the library and both me and Oliver decided to schedule this review only after we determined that all issues had been addressed or at least considered. In your review please state whether the acceptance conditions have been addressed satisfactorily. ---------------------------------------------------------------------------------- About the library: Boost.Context is a foundational library that provides a sort of cooperative multitasking on a single thread. By providing an abstraction of the current execution state in the current thread, including the stack (with local variables) and stack pointer, all registers and CPU flags, and the instruction pointer, a context instance represents a specific point in the application's execution path. This is useful for building higher-level abstractions, like coroutines and fibers. ---------------------------------------------------------------------------------- Useful Links: documentation: http://ok73.ok.funpic.de/boost/libs/context/doc/html/ library: git://github.com/olk/boost.context.git ---------------------------------------------------------------------------------- > From the original review result email: Point to be addressed before the mini review: Design 1. Separation of the context class in two interface: - A C-like interface that defines a POD struct that is memcpy-able and that can be implemented either using platform libraries, as ucontext, fibers or directly using assembler when a robust implementation is available. The context swap implementation don't need to save the signals as ucontext does. The following is just for illustrations purposes. struct boost_context; typedef void boost_context_fn_t(intptr_t); extern "C" void boost_context_make(boost_context* ctx, boost_context_fn_t * f, intptr_t p, ...); extern "C" void boost_context_swap(boost_context* from, boost_context const* to); extern "C" intptr_t boost_context_destroy( boost_context* fc); boost_context_make is a merge of get_context with make_context + some fields assignations. "A user will have lower expectations from such a low level API and at the same time will give more freedom for other people to implement on top of it higher abstractions as Boost.Corutines, Boost.Fibers ..." - A non-copiable but movable safe context class on top of the low level C-like interface, that will provide modern and efficient C++ interface, that is usable by a user in a safe way. The safe context class would just be one of the client of the C-like interface, other library authors could either use the underlying C-like API directly or the class context depending on wether they need the speed or safety. * The context class will not be templated any more, and the use of type erasure will ensure that. * The constructor will accept any C++ callable, function pointers, functors, ... * At this high level interface, the function provided by the user could throw exceptions, and the library must wrap the user function and needs to store the exception raised and provide an interface to retrieve them. 2. The stack implementation must ensure that the stack is unwound before it is destroyed. A stack should only be safely deallocated if either has been completely unwound or if it doesn't own any resources. A basic stack without protection seems mandatory. For debug purposes it has been required to provide some stack usage functions that allow to know the max size used for example. Implementation 3. The assembler implementation on Windows must be disallowed if the ABI bug reported by Holger is confirmed. As far as Windows provides a fiber implementation that is as efficient as the assembler one, the assembler implementation is not mandatory and the user of the provided Windows fiber is a preferable choice. 4. Most of the 'throw' statements in the context class should actually be asserts. 5. The provided stack should be used to store any context parameters as far as no major impediment is found during the implementation. This will avoid further allocations on the safe context class. Documentation 6. The documentation is very minimalist and should be expanded with a discussion on context switching and use cases. Take care of all the grammar/spelling improvements suggested by the reviewers (It will be great if Jeffrey could review the documentation before the mini-review). Some user land examples should be provided (why not the yield example). 7. The concept of (Movable) Stack must be clearly defined, as it is done in the standard, using expression requirements with semantic constraints. 8. The assembler implementation should be carefully documented, so others could maintain the code and add other implementations if needed. 9. Some performance measure should be added. Providing the number of cycles on each implemented platform would be nice. Build system 10. The default build on a platform must work (It must be ABI compatible with the underlying platform) and take care of the specific features. Of course, the build needs to support cross compiling, so the user should be able to override the default values. Others points that are not required but that can make the library more usable or efficient: 1. The assembler implementations could be simplified if the context itself was represented as a single pointer to the top of the stack. This would save some instructions to move the source address from the stack return address to the context struct and back. 2. Instead of supporting a 'fc_link' a-la ucontext, have the callback function return a new context (it is void now). 'fc_link' is useful only on some limited cases (usually when you have an external scheduler managing your contexts), while the having the callback return the 'next continuation' has more applications (note that fc_link can be implemented easily in term of the continuation returning variant, but the reverse is harder). This will be very useful, for example, to implement some kind of 'exit_to' functionality (unwind the stack and restore another context), a key piece for safe context destruction. 3. Give to boost_context_swap the ability to exchange a parameter with the other context: boost_context_parm_t boost_context_swap( boost_context * ofc, boost_context const* nfc, boost_context_parm_t parm) where boost_context_parm_t is either union boost_context_parm_t { void * ptr; int int_; }; or simply intptr_t; boost_context_swap saves the current context in ocf and restores the context ncf as usual; additionally, if ofc was 'captured' on a call to boost_context_swap, this call will return the value of parm on the original context. This extra parameter is equivalent to the second parameter of longjmp. If ofc was created with boost_context_swap, 'parm' will be an extra parameter to the function. Note that this can be potentially implemented with little or no overhead. 4. Add a variant of boost_context_swap that allows executing a function on the destination context (in this case 'parm' would be passed parameter to this function. This is mostly useful for injecting an exception on the destination context. This can be potentially implemented on top of the existing functionality, but would slow down every context switch; a possible efficient implementation would manipulate the destination stack to add a call to the function on top of it, so that the cost is paid only when required. 5. Add a current context function (thread local). _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

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