July 2009 - Boost - lists.preview.boost.org

Re: [boost] Proposal: MapReduce library (single machine)
by Mateusz Berezecki 31 Aug '09

31 Aug '09

Hi , I've just joined this mailing list because of this particular discussion :-) >> 2) have a plan so that the library can eventually range from >> working on 1 multi-core system to distributed >This is the eventual goal, and I have designed the library to be extensible >to be able to do this in the future. With the policy based designed, making >use of the open source projects that you mention should be non-intrusive; >the library allows the user to supply a handler for the intermediate files >(to use kosmosfs or hypertable, for example) I'm going to give it a spin as it happens I'm already having a half-baked distributed backend lacking a mapreduce library for both hypertable and KFS and report back. But this is interesting! Can't stop thinking about it now :-) best, Mateusz

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[rfc] cppgui
by Felipe Magno de Almeida 27 Aug '09

27 Aug '09

I've been working the past two years, on and off, unfortunately more often not, in a GUI library. But I have gotten back to it. And I wanted to make it usable. I believe there are some great things in it. This library has a named parameter interface which is extensible by the backend implementation. I've been working on a QT port, which have been fairly easy so far. My intention is to rework some parts of it, finish most widgets and the surface concept I've been working on and submit to review to boost. But I wanted some ideas on the controller interface and whatever might be useful too in improving the design before submitting. The library is in http://www.assembla.com/wiki/show/cppgui There's a svn and trac there that I use. The library requires the boost/funcitonal/factory.hpp library reviewed and accepted (?), which is not yet part of any boost distribution to compile. You will also need fusion to compile. I've tested with GCC 4.4.0/4.3.3 with QT and win32 with visual C++ 9.0. But should be pretty portable, including qt in visual C++. The gtk code does not compile :(. There are some very primitive documentation in the site, and some examples in the svn. Thanks in advance, -- Felipe Magno de Almeida

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[unordered] allocators and EBO
by Thorsten Ottosen 24 Aug '09

24 Aug '09

Hi James, (Sorry I called you Jeremy in the other post). When the allocator is empty, you should avoid storing them as members in different internal structures, and make the allcator a base class of some of these structures. Thanks -Thorsten

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[fusion] Minor interface change
by Joel de Guzman 23 Aug '09

23 Aug '09

Hi Y'all, Heads up. There will be a minor interface change. vector0 will now be a template: vector0<> to better reflect MPL. This also addresses Boost Trac ticket #1608: https://svn.boost.org/trac/boost/ticket/1608 Please adjust your code accordingly, or holler if you have any complaints. Unless there are objections, I'll commit the code as soon as all the relevant regression tests pass. Regards, -- Joel de Guzman http://www.boostpro.com http://spirit.sf.net

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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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[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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[C++0x] Report from Frankfurt committee meeting
by Beman Dawes 17 Aug '09

17 Aug '09

The C++ standards committee met in Frankfurt, Germany, last week. Key actions: * Concepts have been removed from C++0x. The committee is very much in favor of Concepts. But Concepts are seen as so important that they have to be right. And the strong consensus was that getting Concepts right, for any reasonable definition of "right", would add several years to the schedule. There was also a consensus that an implementation of a compiler that could compile the entire standard library is part of the definition of "right". While ConceptGCC has been a great help, it isn't there as far as validating "right". Personally, I think Clang may end up being the compiler that eventually validates Concepts. * The range-based for loop and some other library features that were dependent on Concepts will be retained by recasting them to no longer depend on Concepts. See a paper in the upcoming post-meeting mailing to see how range-based for loops will work. * A second Committee Draft (CD2) will need go out for public comment in the Spring or Summer 2010, given the amount of change required to remove Concepts. The C++0x final schedule will thus slip about one year. * No committee action was taken as to how Concepts will eventually make it into C++. While there was a bit of discussion about doing a Concepts Technical Report (TR), there was no such proposal made. Committee members seem to lean toward letting the two rival Concept teams go back to work outside of the committee process. The expectation being they will come back to the committee when they are ready to restart the standardization process. Hopefully the lessons learned about Concepts during the committee process will be taken advantage of, so future standardization of Concepts will be smoother. My personal opinion is that removing Concepts will speed the arrival of conforming C++0x compilers. GCC, for example, has already implemented much of C++0x, so their key developers are no longer faced with the difficult task of turning ConceptGCC into a production compiler, and can concentrate on remaining major features like lambdas. Although Concepts would have added a lot to C++ and Boost, Concepts would also have presented major migration challenges. I'm thinking that for most Boost libraries, migration to C++0x will now be easier and less disruptive. We need to focus on the bright side. --Beman

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Vault access for Boost.Debug
by Zachary Turner 11 Aug '09

11 Aug '09

Hello, I'd like to request access to the vault. I'm going to upload a proof-of-concept of some of the things I mentioned earlier in my thread about Boost.Debug. This early version gives simple stack traces in limited scenarios, only supports Windows, and isn't designed very well. Here's an example of a program using it in its current form: void test_func(int argc, int argc2, char* argv[]) { stack_trace trace(10); //Maximum depth of 10 levels std::cout << trace.string() << std::endl; } int main(int argc, char* argv[]) { test_func(argc, argc, argv); return 0; } and an example of the stack trace printed as a result of this program: void test_func(int, int, char**) [f:/dev/stack_trace/main.cpp:10] int main(int, char**) [f:/dev/stack_trace/main.cpp:23] int __tmainCRTStartup() [f:/dd/vctools/crt_bld/self_x86/crt/src/crtexe.c:406] int mainCRTStartup() [f:/dd/vctools/crt_bld/self_x86/crt/src/crtexe.c:389] It also currently supports printing the names of all the arguments, but it was hackish and I left it out until it undergoes some redesign. There is currently no documentation, but as this is just a proof of concept I'm currently only looking for people to help out with actual code and/or provide input, so I think that's ok for now. Thanks

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enum / string translation
by Zachary Turner 11 Aug '09

11 Aug '09

I wrote some code to perform both compile-time and runtime translation between enums and their corresponding string values. The only direction that isn't possible is string->enum at compile time. Is there any interest in this? You can use it as follows: typedef enum { ValueA1, ValueA2 } EnumA; typedef enum { ValueB1, ValueB2 } EnumB; BEGIN_ENUM_MAP_DECLS() BEGIN_ENUM_MAP(EnumA, a_map) ENUM_MAP(ValueA1) //maps ValueA1 to the string "ValueA1", provides both compile-time and run-time lookups. ENUM_MAP_NAME(ValueA2, "custom name") //maps ValueA2 to the string "custom name", provides both compile-time and run-time lookups END_ENUM_MAP() BEGIN_ENUM_MAP(EnumB, b_map) ENUM_MAP(ValueB1) ENUM_MAP(ValueB2) END_ENUM_MAP() END_ENUM_MAP_DECLS() void foo() { //value -> string, compile time BOOST_STATIC_ASSERT(enum_map<EnumA>::value_lookup[ValueA2] == "custom name"); //value -> string, runtime EnumB some_value = get_enum_b_from_external_source(); std::cout << "some_value = " << enum_map<EnumB>::name_lookup[some_value] << std::endl; //prints either 'some_value = ValueB1', or 'some_value = ValueB2' //string -> value, runtime EnumA value = enum_map<EnumA>::name_lookup["custom name"]; BOOST_ASSERT(value == ValueA2); } One particularly useful application of this that I've found is with regards to boost::program_options. You can provide an overload of boost::program_options::validate that uses boost::enable_if with boost::is_enum thus providing automatic support for entry of friendly names corresponding to enumerations on the command line or in a config file. Obviously there's many other easily identifiable uses as well. However, this is a common enough problem that I wonder if anyone else has already attempted something like this, and if so maybe I can look at their code first, or just scrap mine altogether and reuse something existing. If not, I'm sure there is plenty of room for improvement in mine but if it could fit somewhere in boost (perhaps boost/utility) I'd be willing to submit it and make necessary improvements. Unfortunately I don't think it's technically possible to have a simple syntax, even through preprocessor magic, that requires you to only specify the name of each enumerated value once, and end up providing both a definition of the enumeration as well as the mapping from string<->value, but if someone comes up with a way that would obviously be ideal.

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