June 2012 - Boost - lists.preview.boost.org

Tickets 6123 an 7023
by Luke Camden 29 Jun '12

29 Jun '12

Hi, Is anyone willing to commit these patches for me? If the process is not too involved I don't mind rtfm & DIY as an answer. Cheers, Luke

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[1.50.0] Boost release 1.50.0 available
by Beman Dawes 29 Jun '12

29 Jun '12

Release 1.50.0 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This release contains four new libraries (Algorithm, Functional/OverloadedFunction, LocalFunction and Utility/IdentityType) and numerous enhancements and bug fixes for existing libraries. For details, including download links, see http://www.… [View More]

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Re: [boost] Policy proposal: All user-visible exceptions should be thrown through BOOST_THROW_EXCEPTION
by Brian Wood 29 Jun '12

29 Jun '12

Emil Dotchevski: >On Wed, Jun 27, 2012 at 7:46 AM, Brian Wood <woodbrian77(a)gmail.com> wrote: >> Emil Dotchevski: >> >> > >> > There are 3 aspects of boost::throw_exception: >> > >> > 1) it enables libraries to support BOOST_NO_EXCEPTIONS configurations, >> > 2) it enables boost::error_info, and >> > 3) it enables boost::exception_ptr. >> > >> > 1) and 2) have nothing to do with threads; 3) implements … [View More]

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Exact Decimal library
by Andrew Robb 29 Jun '12

29 Jun '12

Introduction C++ needs UTF-8 text (Boost.Locale) and exact decimal types support. Together they allow full processing of modern business text. Normal existing binary exponent types (float, double and long double) are not suitable for exact decimal numbers. The IEEE 754-2008 decimal exponent types should be allowed in binary files. Most processors already use IEEE 754-1985 for binary exponent types. IBM processors already support IEEE 754-2008 decimal exponent types in hardware and can used for … [View More]optimization for exact decimal. Other processors may use fixed-point exact decimal. Exact Decimal Exact decimal numbers indicate not only the value but also the precision. Thus 0.3 and 0.30 indicate the same value but with different precisions. With rounding, the value 0.3 indicates a value between 0.25 and 0.35 but the value 0.30 indicates a value between 0.295 and 0.305. These are different ranges albeit different around the same centres but must be considered different because of their precisions. Currency values are ‘exact’ as there is no legal or commercial meaning in between the smallest adjacent values defined precision. Even when the GBP went decimal with a halfpenny coin, most banks would only keep values to the penny. A lot of normal commercial exact decimal values can be held in 32-bit with fixed-point decimal to 2 places (USD, EUR and GBP currencies) up to about 20,000.00 - more than enough for weekly groceries. As such, they are as quick as 32-bit integers for addition and subtraction an nearly as fast for multiplying too. Exact decimal processing would not require IEEE 754-2008 decimal exponent types and could use decimal fixed-point indest. Indeed, the range of significand could be more than used by IEEE 754-2008 decimal exponent types (e.g. java.math.BigDecimal). Embedded processors can support fast exact decimal their own way (floating or fixed). http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1169.pdf Extensions to support embedded processors must not give a general range decimal fixed-points. http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1176.pdf Extension for the programming language C to support decimal floating-point arithmetic. Again, from IBM and not for decimal fixed-point type. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2009/n2849.pdf Extension for the programming language C++ to support decimal floating-point arithmetic. Unfortunately the paper looks only at the IEEE 754-2008 hardware implementation rather than using decimal fixed-point implementation. The proposed solution might be enough for high-end database servers but not would helpful for x86 and ARM type embedded processors, where power savings for would be allowed by turning off the binary exponential processor as well as improved accuracy. For existing binary exponent types (float, double and long double), I think there should be new format string type (e.g “-123U-12”). This has a signed integer significand and a signed integer binary exponent. The significand cannot have decimals (no decimal point). Those IEEE 754 formats can indicate “Inf” and “NaN” as well (numeric_limits::is_iec559). There is no conversion error from binary exponent to decimal as is suffered currently. The new decimal types use a opaque arrangement. This allows each platform to use its own hardware to best effect. Each value is defined as a fixed number of decimal points. The significand grows or shrinks opaquely to take any value and can change how it works for each type. The fixed number of decimal points can be over the thousands before or after the decimal point. Thus the range of the decimal fixed points will be the same or more than those for decimal exponent types (-6143..6144). The significand has a least maximum 34 digits, again to match for decimal exponent - probably at least 38.23 for 128-bit significand. The method of keeping the significand can change with size and processor. For instance, 32-bit binary is fast on 32-bit processors (or 64-bit native binary). 30-bit (9 digit) or 10-bit (3 digit) decimal can grow (BigDecimal) for thousands of digits. IEEE 754 2008 decimal exponent types for IBM processors (also 10-bit groups of 3 digits) but slow without hardware support. Much of the work of exact decimal are similar to the SQL-92 types for NUMERIC (variable decimal places) and DECIMAL (fixed-point decimal) differ by variable or fixed decimal point. The NUMERIC type is similar to decimal exponent. The DECIMAL fixed-point decimal can be set by template or constructor. Only run-time decimal places available for NUMERIC. We don’t limit the number of decimal places but the SQL-92 types limit decimal places to 0 and number of digits (MySQL 5.0.3 supports 65 digits for NUMERIC and DECIMAL and DB2 supports 31 digits.) Accumulators There should be _Accum that can opaquely contain several decimal fixed-point accumulators of all different sizes (with the same fixed number of decimal points). Thus small efficient accumulators are used with small values. Whereas a _Decimal has a union defining the value, a _Accum might have a structure with similar members. If a overflow comes, its old accumulator value is added the to a slower bigger accumulator and reset the small accumulator. The small accumulator receives small values again. When the values are accumulated, the small accumulators are combined into the largest used accumulator for the final answer. Such a complicated behaviors arrangement needs compilation rather than C++ coding. For instance, using the overflow flag uses information from to the compiler. Operations We are only interested in (commercial) safe exact decimal operations for the following types: _Numeric: decimal exponent _Decimal: decimal fixed-point _Accum: several sized decimal fixed-point accumulators Multiply The exact decimal can be multiplied by other exact decimals and integers. The resulting decimal places are the sum of the right hand side. lhs = one * two; lhs *= integer; // or 0 decimal place Divide We can only divide by integers (or exact decimal with 0 place). The results have the same number of decimals. A divisor of zero will be thrown (no infinity). lhs = rhs / integer; lhs /= integer; Modulo There will be a remainder from a divide. Again with the same number decimals. lhs = rhs % integer; lhs %= integer; Add and Subtract We can add/subtract with other exact decimals with the same number of decimal places. Mixing values with different decimal places may cause problems for exact values (different truncation for instance). lhs = rhs + val; lhs = rhs - val; lhs += val; lhs -= val; Where values with different decimal places need combining explicitly we use trunc() to match the decimal places first. This can increase as well as decrease decimal places. It also allows tracks of errors. Comparison <, <=, ==, !=, >= and > between exact decimals with the same number of decimal places. Collections Any _Decimal collection can be limited to values with the same decimal fixed-point places. Truncation The binary exponent values float, double and long double have separate approximate values 1.3f, 1.3 or 1.3L for different sizes. I propose another exact decimal value, for example 1.300d for three decimal places. Alternatively use exact decimal exponent 1300e-3d version (using integer significand). Value Approximation 1.3f - 1.2999999523162841796875.. 1.3 - 1.3000000000000000444089209850062616169452.. 1.3L - 1.3000000000000000000000000000000000385185.. 1.300d or 1300e-3d - 1.300 (exact) Where a value is not the precision, we must expand or truncate to required decimals places and should choose a method of truncation (matched to IEEE 754-2008): ceil - the most negative answer not less than the original floor - the most positive answer not greater than the original zero - the answer furthest from zero not further than the original (the usual C method) round - the answer nearest the original choosing the most positive in case of a tie bank# - like round but choosing the even last digit in case of a tie expand - not truncation (zero padding) and the error should be zero As well as tructaton is then required value, there were be a leftover (similar in % value with a /). By keeping a record of truncation we can assess of errors. template <typename T> _Decimal & _Decimal::trunc(TRUNC, T const &source, T *error = 0); This will be a preferred way to convert binary exponent types into a decimal value for printing. Formatting For place 0 decimal format like integer and between places 1 and 9, the format will be decimal and trailing zeros are significant. Otherwise with the default format will be a exponent (matched to the decimal) with a integer significand. They will resemble binary float types, except that they are accurate and avoid decimals in the significand. 123 (0 decimal place so no decimal point) -0.012340 (6 decimal places) -12340e-12 (12 decimal places or decimal exponent -12) Final number formatting will be up to Boost.Locale using Unicode. [View Less]

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Range notation grammar
by Dave Abrahams 29 Jun '12

29 Jun '12

This ship has undoubtedly sailed, but I'd like to register my displeasure with names like "uniqued," "taken," and "strided" et. al. The effect (subjectively of course) is to take a beautiful, minimal abstract notation that reflects a common practice (seriously, it's "grep," which is a verb, not "grepped") and mess it up with unconventional and awkward linguistic insurance against misunderstanding. this-has-been-a-test-of-the-emergency-nattering-system-ly y'rs, -- Dave Abrahams BoostPro … [View More]

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date_time bug.
by GAURAV GUPTA 29 Jun '12

29 Jun '12

Hi All, I have reported one bug: Ticket No:7022. (Link is https://svn.boost.org/trac/boost/ticket/7022 ) As I have tracked. the owner (you can see it on ticket information) assigned to my ticket is not active. I have not found any posts by him newer that year 2007. So, could anyone help in verifying my patch for the reported bug?. I found this bug using some tool. Please reffer the ticket No. 7022 -- Regards, Gaurav

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[review] status of Boost.Conversion?
by Nathan Ridge 29 Jun '12

29 Jun '12

Hi, I am wondering, what is the status of the Boost.Conversion library? On the Review Schedule page, it indicates that a review had taken place in August 2011 and the results of the review are "pending". Does anyone when the results will be forthcoming? Thanks, Nate

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JNI library
by Felipe Magno de Almeida 28 Jun '12

28 Jun '12

Hello Boosters, I'm developing a JNI library for writing native code in C++ for Java and calling Java code within C++, using JNI as interface to the JVM. Is there any interest in this library? Regards, -- Felipe Magno de Almeida

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[Survey] utf8_codecvt_facet::do_length parameter
by Marshall Clow 28 Jun '12

28 Jun '12

There's some confusion in boost (and in various standard libraries) as to the declaration of std::codecvt<>::do_length The '03 and '11 standards say: > template <class internT, class externT, class stateT> > class codecvt : public locale::facet, public codecvt_base { > // blah blah blah > virtual int do_length(stateT&, const externT* from, const externT* end, size_t max) const; > }; But some standard libraries (notably older Dinkumware libraries, and … [View More]

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[1.50.0] Release candidate 2 available for testing
by Beman Dawes 28 Jun '12

28 Jun '12

Release candidate 2 files for 1.50.0 are available at http://boost.cowic.de/rc/ RC 2 is supposed to fix the --layout build problems reported for RC 1. As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. Thanks, --Beman --PS: I tested the 7z version, and it … [View More]

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[chrono] chrono/config.hpp enforces that time.h defines CLOCK_REALTIME; should it?
by Krzysztof Czainski 28 Jun '12

28 Jun '12

Hello, Suppose I want to use durations, and time_points with a user defined clock. I don't want to use any clocks provided by Boost.Chrono. My compiler provides a <time.h>, which doesn't define CLOCK_REALTIME, which chrono/config.hpp reports as an error. This prevents me from using parts of Chrono, that I believe don't depend on anything from <time.h>. I am able to work around this by simply defining CLOCK_REALTIME. But I would like to ask: Could Boost.Chrono allow using duration.… [View More]

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Re: [boost] Policy proposal: All user-visible exceptions should be thrown through BOOST_THROW_EXCEPTION
by Brian Wood 27 Jun '12

27 Jun '12

Emil Dotchevski: > On Tue, Jun 26, 2012 at 10:24 AM, Brian Wood <woodbrian77(a)gmail.com> wrote: >> >> Is there a penalty for single threaded applications here? There's >> been discussion of the support for transferring exceptions between >> threads; are there aspects of that support that are unneeded in a >> single threaded context? >> > > There are 3 aspects of boost::throw_exception: > > 1) it enables libraries to support … [View More]

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Re: [boost] program options (consider using BOOST_THROW_EXCEPTION)
by Leo Goodstadt 27 Jun '12

27 Jun '12

> On 22 June 2012 17:51, Vladimir Prus <ghost(a)cs.msu.su> wrote: > > > On 22.06.2012 11:33, Emil Dotchevski wrote: > > > >> On Thu, Jun 21, 2012 at 11:44 PM, Vladimir Prus<ghost(a)cs.msu.su> wrote: > >> > >> On 20.06.2012 07:44, Rowan James wrote: > >>> > >>> On a related note; is there interest in a patch set to use > >>>> BOOST_THROW_EXCEPTION to add this (yes, programmer-… [View More]oriented) information > >>>> to > >>>> the exceptions thrown by Program Options and/or other Boost libraries? > >>>> > >>>> > >>> Sorry, but I kinda miss context here (and I did read your original post). > >>> What are advantages of > >>> using BOOST_THROW_EXCEPTION and what are drawbacks? Could you summarize > >>> those for me? > >>> > >>> > >> Allow me :- > >> > >> BOOST_THROW_EXCEPTION, being a macro, is able to record the file name, the > >> function name, and the line number of the throw, which is useful when > >> diagnosing unexpected exceptions: > >> > >> catch(...) > >> { > >> std::cerr<< "Unexpected exception caught. Diagnostic information > >> follows.\n"; > >> std::cerr<< boost::current_exception_**diagnostic_information(); > >> } > >> > >> The exception object is examined dynamically for any and all useful > >> information: type, what(), throw location, any stored boost::error_info > >> objects, etc. The location of the throw (if available) is formatted in a > >> way Visual Studio understands: double-clicking shows the throw location, > >> similarly to double-clicking compile errors. > >> > >> The downside is that when templates are involved, BOOST_CURRENT_FUNCTION > >> (invoked by BOOST_THROW_EXCEPTION) can bloat the code. There is a Trac > >> ticket for this. > >> > > > > Emil, > > > > thanks for explaining. Given the above, I am not sure I am interested in > > using > > BOOST_THROW_EXCEPTION for program_options, given that exceptions are used > > there to report > > user mistakes mostly, and so function name or file line is of limited > > interest. > > > > Thanks, > > Volodya > > > Thanks Emil. > > If I can make the case in favour of BOOST_THROW_EXCEPTION, it is for the > very reason that they are reporting user mistakes. The throw location for > an exception is typically accompanied by, or at least close to, the logic > that delineates such a user mistake from acceptable input. As such, it is > a useful remedy in itself; but also gives the user specific information for > finding documentation relevant to fixing the error. Without it, we have at > best the entry point into the library that; and often a lot less if the > exceptions are caught at a higher level. > > Documentation for valid inputs or states to a function can only say so much > about all the possible errors or exceptions that may occur. To elaborate on what Volodya said, program_options is unusual (for Boost) library in its use of exceptions: Most of the time, exceptions are there to inform the programmer of an error in the programme. However, the majority of exceptions in program_options are there to indicate a problem in the construction of the command line by the *end-user* (not the programmer). In other words, the program *is* working exactly as designed. The programmer has no interest in the provenance of these exceptions *except* that they can be used to inform the end-user how they should retype the command line and try again. So, for example, ten times a day, I will type something like ls --colour * and ls will tell me ls: unrecognized option '--colour' and I will know to retype the US spelling... ls --color * If "ls" were using program options, an unrecognised option exception message will be thrown which eventually allows this informative message to be displayed before exiting. It is entirely unhelpful for the end-user to have Exception XXX on line xxx of file yyy.... To make it easier to use program options *in English*, the exception messages have been recently rewritten to be maximally informative to the end-user rather than the programmers. Thus we can take e.what() and write it out to std::cerr without further ado. Of course, for localisation, these error messages have to be reconstructed in the appropriate language. Hopefully, there is enough data in each exception to allow this. Curiously, the current design of exceptions in program_options ended up try to mirror what Emil has done in BOOST_THROW_EXCEPTION. When the exception is thrown deep in the bowels of the command line parsing, it does not have the full context which would allow an informative message to be constructed. The exception has to be propagated up, and then "decorated" before being rethrown. The alternative was to pass the full context down the function call hierarchy to each point at which exceptions can be thrown. This made the code horribly convoluted and ugly, and provoked loud cries of anguish from Volodya. Leo [View Less]

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Interest in static multidimensional array.
by Brian Smith 27 Jun '12

27 Jun '12

Hi All, Some time ago I uploaded the maps folder, to Boost's sandbox, containing various multidimensional and mathematical arrays. The resulting discussion appeared to indicate some interest in the multidimensional arrays and that the overall design required some reworking. Having now had the opportunity to use a compiler supporting variadic templates, I have rewritten the static multidimensional array class using them. The class, documentation, and some tests are available at, https://github.… [View More]

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[pool] Objects of varying sizes
by Robert Dailey 27 Jun '12

27 Jun '12

Is it possible to create a pool for polymorphic types? For example: class A; class B : public A; class C : public A; I want to create a pool of type A, but the allocation can be for B or C at any time. Will this work?

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[build] Problem building boost libraries from trunk with layout versioned
by Thomas Heller 27 Jun '12

27 Jun '12

Hi, I am trying to build current trunk with layout versioned. Boost build is currently failing. This looks similar to the problem reported with the 1.50 RC. Here is the error: [heller@faui32m trunk]$ ./b2 toolset=intel --layout=versioned -j2 variant=debug Building the Boost C++ Libraries. Performing configuration checks - 32-bit : no - 64-bit : yes - x86 : yes - has_icu builds : yes warning: Graph … [View More]library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam - iconv (libc) : yes - icu : yes - gcc visibility : yes - long double support : yes warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. /home/heller/programming/boost/trunk/tools/build/v2/build/virtual-target.jam:1079: in virtual-target.register-actual-name from module virtual-target error: Duplicate name of actual target: <pstage/lib>libboost_context-il-mt-d.so error: previous virtual target { symlink%symlink.ln-libboost_context-il-mt-d.so.SHARED_LIB { common%common.copy-libboost_context-il-mt-d-1_50.so.1.50.0.SHARED_LIB { intel-linux%intel-linux.link.dll-libboost_context-il-mt-d-1_50.so.1.50.0.SHARED_LIB { intel-linux%intel-linux.compile.asm-asm/fcontext_x86_64_sysv_elf_gas.o.OBJ { asm/fcontext_x86_64_sysv_elf_gas.S.ASM } } { intel-linux%intel-linux.compile.c++-fcontext.o.OBJ { fcontext.cpp.CPP } } { intel-linux%intel-linux.compile.c++-stack_allocator_posix.o.OBJ { stack_allocator_posix.cpp.CPP } } { intel-linux%intel-linux.compile.c++-stack_utils_posix.o.OBJ { stack_utils_posix.cpp.CPP } } } } } error: created from ./stage-unversioned error: another virtual target { symlink%symlink.ln-libboost_context-il-mt-d.so.SHARED_LIB { symlink%symlink.ln-libboost_context-il-mt-d-1_50.so.SHARED_LIB { common%common.copy-libboost_context-il-mt-d-1_50.so.1.50.0.SHARED_LIB { intel-linux%intel-linux.link.dll-libboost_context-il-mt-d-1_50.so.1.50.0.SHARED_LIB { intel-linux%intel-linux.compile.asm-asm/fcontext_x86_64_sysv_elf_gas.o.OBJ { asm/fcontext_x86_64_sysv_elf_gas.S.ASM } } { intel-linux%intel-linux.compile.c++-fcontext.o.OBJ { fcontext.cpp.CPP } } { intel-linux%intel-linux.compile.c++-stack_allocator_posix.o.OBJ { stack_allocator_posix.cpp.CPP } } { intel-linux%intel-linux.compile.c++-stack_utils_posix.o.OBJ { stack_utils_posix.cpp.CPP } } } } } } error: created from ./stage-unversioned error: added properties: none error: removed properties: none /home/heller/programming/boost/trunk/tools/build/v2/build/virtual-target.jam:490: in actualize-no-scanner from module object(file-target)@3737 /home/heller/programming/boost/trunk/tools/build/v2/build/virtual-target.jam:135: in object(file-target)(a)3737.actualize from module object(file-target)@3737 /home/heller/programming/boost/trunk/tools/build/v2/build-system.jam:750: in load from module build-system /home/heller/programming/boost/trunk/tools/build/v2/kernel/modules.jam:283: in import from module modules /home/heller/programming/boost/trunk/tools/build/v2/kernel/bootstrap.jam:142: in boost-build from module /home/heller/programming/boost/trunk/boost-build.jam:17: in module scope from module It seems to work when using --layout=system Anyone knows a fix to this? FWIW, toolset=gcc has the same problem Thanks, Thomas [View Less]

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program options (consider using BOOST_THROW_EXCEPTION)
by Roger Martin 27 Jun '12

27 Jun '12

Hi boost, At version 1.49.0 In testing command line with known unknowns such as -V a location unknown exception is thrown from inside program_options recommending to use BOOST_THROW_EXCEPTION. I've been trying to find this and apply BOOST_THROW_EXCEPTION to eliminate the verbosity for users: ---- Command line incorrect: Throw location unknown (consider using BOOST_THROW_EXCEPTION) Dynamic exception type: boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector… [View More]

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[stl_ext_adv] array based B+ tree
by Vadim Stadnik 27 Jun '12

27 Jun '12

Hi all, First of all, I would like to thank all Boosters for previous useful discussion of dynamically allocated augmented B+ trees. The development of the new array based variant of a B+ tree has been significantly influenced by these comments and suggestions. The problem of the C++ standard sequences based on linear data structures is that every of them has at least one inefficiency, such as linear cost of insert(), erase() functions of std::vector or slow bidrectional iterators of std::… [View More]list. These inefficiencies create performance bottlenecks and significantly complicate the development of efficient general algorithms based on STL sequences. The new variant of an array based B+ tree offers a solution to these problems of STL sequences by reducing the running time of inefficient operations from linear to logarithmic in the worst case. The array based B+ tree implements a simple partition of an array into a list of sub-arrays connected to a B-tree. Compared to dynamically allocated B+ trees the new tree requires less space and improves locality of reference. In some aspect the array based B+ tree represents an enhanced pool allocator. Performance of the new tree has been optimized for container operations with large numbers of elements. In a number of tests the improvement factor is about 10. A significant advantage of the array based B+ tree over standard sequences is the support of splice() functions with logarithmic running time in the worst case. The high efficiency of these functions extends move semantics for non-intrusive STL sequences, since they allow user algorithms to insert and remove any range of consecutive elements. This high efficiency is not available in standard containers of C++03 and C++11. The splice() function of std::list has linear running time in the worst case. For a discussion of this problem by Boost community, please have a look at this thread: http://boost.2283326.n4.nabble.com/Containers-How-about-a-list-with-O-1-spl… For associative containers the array based B+ tree offers random access iterators and improved efficiency of many container operations against dynamically allocated B+ trees. In the general case associative containers cannot benefit from the splice() functions. Nevertheless, they can be used in algorithms for efficient split operations, since these operations do not change the order of elements in obtained containers. I think that the array based variants of B+ trees are very important, since they offer a number of performance benefits and can be used in many areas from mobile applications to processing huge data sets. The new array based B+ tree is described in this document: http://dl.dropbox.com/u/51041088/stl_ext_adv_doc/doc/array_based_bp_trees.h… The project with source code and tests: https://github.com/vstadnik/stl_ext_adv The new file with implementation of the array based B+ tree: https://github.com/vstadnik/stl_ext_adv/blob/master/container/bp_tree_array… I will appreciate any comments, suggestions and ideas concerning augmented array based B+ trees and STL variants of containers using these data structures. Regards, Vadim Stadnik [View Less]

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Re: [boost] Policy proposal: All user-visible exceptions should be thrown through BOOST_THROW_EXCEPTION
by Brian Wood 26 Jun '12

26 Jun '12

Pete Bartlett: < snip > > Cons for 1) and 2): > - Always paying for the cost of #including <boost/throw_exception.hpp> > - All libraries are dependent on - and therefore become vulnerable to any > future breakages (if any) in - Boost.Exception. Is there a penalty for single threaded applications here? There's been discussion of the support for transferring exceptions between threads; are there aspects of that support that are unneeded in a single threaded context? … [View More]

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Re: [boost] Interest in a "breadth first" algorithm?
by Brian Wood 26 Jun '12

26 Jun '12

Gary Powell: > > A while ago I needed to serialize and de-serialize a std::map and I > realized that the only interface was begin(), end() which of course meant > that re-creating this same map was the least efficient way possible, as all > the elements were added in sorted order. Because I wrote them out using > begin() -> end() So I wrote a breadth first template which takes a > container, a template to use as the core of a queue, a template for the > allocator, … [View More]

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Re: [boost] Boost and exceptions
by Stewart, Robert 26 Jun '12

26 Jun '12

Robert Ramey wrote: > Dave Abrahams wrote: > >> I mean, if there is a problem with boost::throw_exception or > >> any other part of Boost Exception, I'd like to know about > >> it. > > > > It seems clear to me from his posts that Robert wants to > > talk about the process and has forgotten any specifics about > > actual problems. > > > The problem was the gratuitious inclusion of a new dependency. Emil has described repeatedly why … [View More]the change was not gratuitous. That you fail to recognize the value in the change does not make it gratuitous. I looked at a recent boost/throw_exception.hpp. It includes boost/exception/detail/attribute_noreturn.hpp. That creates a dependency inversion that is unfortunate. That is, a top-level header file depends upon a header file of a library's files. That header is very short and has nothing Boost.Exception specific, so the code could be moved into boost/throw_exception.hpp or boost/detail/attribute_noreturn.hpp, for example. The header also conditionally includes the non-trivial boost/exception/exception.hpp, another dependency inversion, which defines many types and functions, and includes some inline function definitions: boost::exception_detail::refcount_ptr boost:: error_info boost::exception boost::exception_detail::error_info_base boost::exception_detail::type_info_ boost::exception_detail::error_info_container boost::exception_detail::get_info boost::exception_detail::get_diagnostic_information() boost::exception_detail::copy_boost_exception() boost::exception_detail::set_info() boost::exception_detail::error_info_injector boost::enable_error_info() boost::exception_detail::clone_base boost::exception_detail::clone_impl boost::enable_current_exception() If BOOST_EXCEPTION_DISABLE is not defined, then boost::throw_exception() tacks on Boost.Exception features to the exception being thrown. This is a non-trivial set of changes to make to the top-level header. I didn't follow the discussion at the time, but I'll presume there was a lot of discussion about the type and extent of these changes and that it was considered a good idea. In hindsight, I agree with Robert's assertion that there should have been a replacement function, boost::exception::throw_exception() or similar, to introduce the new functionality. Whether the existing function needed to be deprecated is a separate issue. The result is that libraries could knowingly choose the new version, and a dependency on Boost.Exception, or, if warranted, stick with the old. As things now stand, if there is good reason to avoid the new version, it can only be done by defining BOOST_EXCEPTION_DISABLE, which affects an entire build. > The extent/nature of any problem it created or didn't create is > not relevant here. Just the injection of a new body of code > which replaced two lines and added no functionality used/needed > by the serialization library makes the any library which used > boost::throw_exception "bigger" for no reason. The issue you're raising, as I understand it, is dependency inversion: the top-level header brings a dependency on Boost.Exception. > It makes the library more "fragil". It means I have I a new > place to look if something needs looking into. etc.etc. As Nevin pointed out, your code will always be subject to the changes in those libraries on which it depends. The more dependencies you introduce, the more fragile your code becomes, but there's a great deal of benefit to reuse, too. The only issue in this case is that one can reasonably expect a top-level header to avoid dependencies on libraries. > So we'll just move on as Vicente suggested. That will be > satisfactory from my standpoint. That is the only way forward, if there is good reason to avoid the now longstanding changes to boost::throw_exception(). However, you should work with Emil to be sure you correctly and fully understand the issues before deciding that you cannot accept boost::throw_exception() as is. (I don't pretend to know what your concerns are. I just don't want to see a new throw_exception() variant if there isn't a compelling reason, and I don't consider your fragility argument compelling in this case.) _____ Rob Stewart robert.stewart(a)sig.com Software Engineer using std::disclaimer; Dev Tools & Components Susquehanna International Group, LLP http://www.sig.com ________________________________ IMPORTANT: The information contained in this email and/or its attachments is confidential. If you are not the intended recipient, please notify the sender immediately by reply and immediately delete this message and all its attachments. Any review, use, reproduction, disclosure or dissemination of this message or any attachment by an unintended recipient is strictly prohibited. Neither this message nor any attachment is intended as or should be construed as an offer, solicitation or recommendation to buy or sell any security or other financial instrument. Neither the sender, his or her employer nor any of their respective affiliates makes any warranties as to the completeness or accuracy of any of the information contained herein or that this message or any of its attachments is free of viruses. [View Less]

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[contract] relaxing preconditions in subcontracting
by Andrzej Krzemienski 26 Jun '12

26 Jun '12

Hi Lorenzo, I am trying to understand how the feature of relaxing preconditions in overridden functions work or should work. Given the situation, where I call an overridden function via base class reference: *struct Base { virtual void fun(bool b) = 0 precondition{ b == true }; }; struct Deriv : Base { void fun(bool b) override precondition{ true }; }; void test( Base & b ) { b.fun(false); **// broken contract or not?** }* Should this be treated as a broken contract or not? My … [View More]

2 7

boost with cxxflags=-Zc:wchar_t-
by Renato Tegon Forti 25 Jun '12

25 Jun '12

Hi All, I'm mixing QT and boost and noticed problems with wchar_t! I need to compile boost: cxxflags =-Zc: wchar_t- Would like to know what problems I can find! anyone ever had to use 'wchar_t-"? Libs that I am using: boost_mpi boost_serialization boost_system boost_filesystem boost_thread boost_iostreams Thanks

3 2

library dependencies and boost modularization [ was Boost and Exceptions]
by Robert Ramey 25 Jun '12

25 Jun '12

Boost has now close to 100 libraries. In addition there are hundreds of smaller but necessary facilities which aren't technically libraries but they add a lot to the "surface area" that one's brain has to be familiar with to take best advantage of boost facilities. There is also a lot of interconnectedness which makes it an even larger task. This wasn't a big deal when boost was 15 libraries - but now it's different. I would like to propose a classification of boost libraries and … [View More]

1 0

[serialization] Reading newer archives - was throwing unsupported_class_version, now crashes
by Nikolay Mladenov 25 Jun '12

25 Jun '12

Hi Robert, I remember that in the past the serialization library was throwing unsupported_class_version exception when reading of archives with future class versions. This no longer seems to be the case. We had older version of software crash when reading newer archive. The only place that I found to mention unsupported_class_version is commented out and I do not understand the attached note: BOOST_DLLEXPORT void iserializer<Archive, T>::load_object_data( basic_iarchive & ar, … [View More] void *x, const unsigned int file_version ) const { // note: we now comment this out. Before we permited archive // version # to be very large. Now we don't. To permit // readers of these old archives, we have to suppress this // code. Perhaps in the future we might re-enable it but // permit its suppression with a runtime switch. #if 0 // trap case where the program cannot handle the current version if(file_version > static_cast<const unsigned int>(version())) boost::serialization::throw_exception( archive::archive_exception( boost::archive::archive_exception::unsupported_class_version, get_debug_info() ) ); #endif // make sure call is routed through the higest interface that might // be specialized by the user. boost::serialization::serialize_adl( boost::serialization::smart_cast_reference<Archive &>(ar), * static_cast<T *>(x), file_version ); } To allow class to read serialized objects of newer version by default seems very dangerous. I generally requires extra work from the class author and without it will most likely crash. So isn't it better to have an additional trait that a class author needs to define, if a class should be allowed read future versions? something like namespace boost{ namespace serialization { template<class T> struct allow_future_versions : mpl::false_ {}; }} #define BOOST_SERIALIZATION_ALLOW_FUTURE_VERSIONS(T) \ namespace boost{ namespace serialization \ { \ template<> struct allow_future_versions<T> : mpl::true_ {}; \ }} and change the code above to: BOOST_DLLEXPORT void iserializer<Archive, T>::load_object_data( basic_iarchive & ar, void *x, const unsigned int file_version ) const { // trap case where the program cannot handle the current version if( ! boost::serialization::allow_future_versions<T>::value && file_version > static_cast<const unsigned int>(version())) boost::serialization::throw_exception( archive::archive_exception( boost::archive::archive_exception::unsupported_class_version, get_debug_info() ) ); ...... Thanks in advance, Nikolay Mladenov Sitius Automation Inc. [View Less]

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[move] GCC bug and aliasing questions
by Tr3wory 25 Jun '12

25 Jun '12

Hi, Yesterday I started using Boost.Move in my project. On gcc I had the same problem like the guys here: http://lists.boost.org/Archives/boost/2011/07/184263.php Namely, I can't define the move constructor nor the assignment operators outside my class... After some time I managed to create a minimal example (19 lines) and sent a bug report to the gcc guys: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53725 So far, so good. In the minimizing process I found something interesting: the … [View More]

3 5

An alternative approach to TypeErasure
by Pyry Jahkola 25 Jun '12

25 Jun '12

Hi all, I was quite impressed by Sean Parent's Friday talk in C++Now! 2012 (see slides in [1], code in [2]) and was left wondering whether the generation of his polymorphic object wrapper could be made simple somehow in C++11. [1]: https://github.com/boostcon/cppnow_presentations_2012/raw/master/fri/value_… [2]: https://github.com/boostcon/cppnow_presentations_2012/blob/master/fri/value… What I ended up with is tricking ADL into allowing the overloading of arbitrary (specifically … [View More]crafted) function objects that I call _callables_, and then letting the user define interfaces by specifying sets of ("member") function signatures with a callable. You can find the code, and my rambling introductory README file, in GitHub: https://github.com/pyrtsa/poly Comments are welcome! * * * Here's a somewhat shorter intro: 1) Create a callable F by simply deriving it from poly::callable<F>: struct draw_ : poly::callable<draw_> {}; constexpr draw_ draw = {}; 2) Or use the convenience macro POLY_CALLABLE(name) to do the same: POLY_CALLABLE(to_string); // type `to_string_` and object `to_string` 3) Overload your callables by overloading the function named `call`, with the callable as first argument: template <typename T> void call(draw_, T const & x, std::ostream & out, std::size_t position) { out << std::string(position, ' ') << x << std::endl; } std::string call(to_string_, int i) { return std::to_string(i); } template <typename T> std::string call(to_string_, std::vector<T> const & xs) { std::ostringstream s; s << '['; auto i = begin(xs), e = end(xs); if (i != e) s << *i++; while (i != e) s << ", " << *i++; s << ']'; return s.str(); } Now you can call ::draw(x, o, p) and ::to_string(x) for several different types of x: ::draw(123, std::cout, 2); // prints " 123" to stdout ::to_string(std::vector<int>(1, 2, 3)); // "[1, 2, 3]" But you can likewise extend ::draw and ::to_string further by overloading them for your own types too. 4) Define an interface by specifying the set of function signatures as template arguments to poly::interface: using drawable = poly::interface< void(draw_, poly::self const &, std::ostream &, std::size_t, std::string(to_string_, poly::self const &)>; Now, the following calls got automatically defined, and forwarded to whatever type you successfully construct a `drawable` from: void call(draw_, drawable const &, std::ostream &, std::size_t); std::string call(to_string_, drawable const &); * * * I am aware that Steven Watanabe has put some astonishing work on his proposed Boost.TypeErasure. I'm open for discussion whether and how his or mine is a better approach, or if we could combine these into an eventual Boost.Interface library or such! * * * PS. Like I mention in my GitHub page, this kind of type erasure is common in functional languages like Haskell or Clojure. The problem they are solving there is known as the Expression Problem. IMO it makes very much sense to have the corresponding construct in C++ too, as we're moving towards a more and more functional style with parallelism and such. Best Regards, -- Pyry Jahkola pyry.jahkola(a)iki.fi https://twitter.com/pyrtsa [View Less]

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Multiprecision Review
by Phil Endecott 25 Jun '12

25 Jun '12

Dear All, Here is my review of the proposed Multiprecision review. First a rant: why have so few people contributed to the discussion or written reviews? I have waited until now before writing this in the hope that others would say something useful, but there has been very little to read. Boost will suffer as a result of this. It has been depressing to see that at the same time the mailing list has been full of other discussions, so the problem is not that people don't have the time … [View More]to contribute. In particular, the long thread about Boost.Exception makes me want to shout "Why Didn't You Say All This When It Was Reviewed?". My view of the proposed library can be summarised as follows: it doesn't do what I want, but maybe it does enough things that other users would like to justify its acceptance anyway. Except probably it doesn't, because if it did those other users would have said so, which they haven't. In particular, I'd like to be able to implement integers of perhaps 128 or 256 bits that behave like the built-in integers. I can quickly throw together something myself that works OK but: - It's difficult to get the last bit of performance because you need to write asm to use the CPU's carry flag; the work-around probably results in a 2X slowdown. - Writing all the operator overloading etc. is tedious. - It's also error prone, as a mistake in e.g. carry propagation might be detected once in very 2^32 operations. It would have been great if this library could have helped with this. Instead, it has produced something worse than my "quick throw-together". It's worse because it has tried to unify this smallish fixed-size type with very large variable-size types, and the compromises necessary to achieve this have sabotaged the performance. It's also worse because it had a subtle bug - which has since been corrected, but I would still not be confident of getting correct answers without verifying against another implementation. Ideally, there would still be some parts of the library that could be useful to me. If the library had been decomposed into data structures vs. algorithms then perhaps I could have applied the algorithms to my simpler data structures. Unfortunately the library has not been organised in this way, and even if it had done the use of sign-magnitude representation might have scuppered any re-use. As far as I can see, the only part of the library that I could re-use would be the expression template front-end, which doesn't seem to improve performance for types of this size anyway. Here are my answers to the standard review questions: What is your evaluation of the design? Not great for my purposes; see above. What is your evaluation of the implementation? I spent half a day chasing down a bug. My observations are that (a) there are subtle bugs, and (b) the code lacks comments or other clues for people like me to quickly pick up what it's all doing. What is your evaluation of the documentation? Satisfactory. What is your evaluation of the potential usefulness of the library? Not useful for me; see above. Did you try to use the library? With what compiler? Did you have any problems? I spent perhaps a day working on a small but real benchmark which was discussed on the mailing list. How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? About a day-and-a-half in all. I've not looked beyond the areas that I've discussed and I'm aware that there is a lot more to the library i.e. non-integer types. Are you knowledgeable about the problem domain? Not especially. Do you think the library should be accepted as a Boost library? No, because (a) I'm not convinced from this discussion that lots of people are waiting for this functionality (see above). (b) Based on previous experience, I'm sceptical about the possibility of the performance of Boost libraries being improved after acceptance. Despite that, I thank John and Chris for their work which is a considerable leap forward from the last "big number" submission, "xint". Regards, Phil. [View Less]

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Contribute
by Merve Temizer 25 Jun '12

25 Jun '12

Hello, I am not sure if this is right place to write but, how can i contribute as a newbie programmer? My main intention is learning C++ deeper by contributing to some open source organizations. Sorry for if it is wrong place. Thanks in advance.

2 1

[fusion] for_each on gcc 4.7
by Daniel Larimer 24 Jun '12

24 Jun '12

I recently attempted to update to gcc 4.7 and code that compiled with 4.5.3 broke. It appears that boost::fusion expects boost::fusion::random_access_traversal_tag to implicitly cast to mpl::bool_<false>. Switching the 3rd argument from mpl::bool_<false> to an extra template arg (that was ignored), seems to fix the compilation errors. Compiled with std=c++11 /usr/local/include/boost/fusion/algorithm/iteration/for_each.hpp:32:9: error: no matching function for call to 'for_each(… [View More]boost::fusion::vector2<double, double>&, const mace::rpc::detail::unpack_sequence<mace::rpc::function_filter<mace::rpc::connection<mace::rpc::json::io> > >&, boost::fusion::detail::fusion_category_of<boost::fusion::vector2<double, double> >::type)' /usr/local/include/boost/fusion/algorithm/iteration/for_each.hpp:32:9: note: candidate is: In file included from /usr/local/include/boost/fusion/algorithm/iteration/for_each.hpp:11:0, from /usr/local/include/boost/fusion/algorithm/iteration.hpp:12, from /usr/local/include/boost/fusion/algorithm.hpp:10, from /Users/dlarimer/projects/mace/libs/rpc/include/mace/rpc/json/io.hpp:13, from /Users/dlarimer/projects/mace/libs/rpc/include/mace/rpc/json/tcp/server.hpp:4, from /Users/dlarimer/projects/mace/libs/rpc/examples/json_tcps.cpp:1: /usr/local/include/boost/fusion/algorithm/iteration/detail/for_each.hpp:130:5: note: template<class Sequence, class F> void boost::fusion::detail::for_each(Sequence&, const F&, mpl_::false_) /usr/local/include/boost/fusion/algorithm/iteration/detail/for_each.hpp:130:5: note: template argument deduction/substitution failed: In file included from /usr/local/include/boost/fusion/algorithm/iteration.hpp:12:0, from /usr/local/include/boost/fusion/algorithm.hpp:10, from /Users/dlarimer/projects/mace/libs/rpc/include/mace/rpc/json/io.hpp:13, from /Users/dlarimer/projects/mace/libs/rpc/include/mace/rpc/json/tcp/server.hpp:4, from /Users/dlarimer/projects/mace/libs/rpc/examples/json_tcps.cpp:1: /usr/local/include/boost/fusion/algorithm/iteration/for_each.hpp:32:9: note: cannot convert 'boost::fusion::detail::fusion_category_of<boost::fusion::vector2<double, double> >::type()' (type 'boost::fusion::detail::fusion_category_of<boost::fusion::vector2<double, double> >::type {aka boost::fusion::random_access_traversal_tag}') to type 'mpl_::false_ {aka mpl_::bool_<false>}' [View Less]

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Re: [boost] [review] Multiprecision review (June 8th - 17th, 2012)
by Keith Burton 24 Jun '12

24 Jun '12

Instant reactions on reading though the documentation : 1) Introduction : I would prefer to see e.g. mp::int128_t rather than mp::mp_int128_t, given the stated purpose of the library. 2) cpp_dec_float : Narrowing conversions are truncating. This is a no-no for the usage I have in mind at the moment. 3) Constructing and interconverting : >> // There is a need to be careful with integer types though: >> cpp_int i = 2; >> // Ooops, this really just multiplies by 3: >… [View More]

3 2

[multiprecision] Last chance for a review.
by John Maddock 24 Jun '12

24 Jun '12

Just to remind everyone that the multiprecision library review is about to come to an end, so it's time to speak up or shut up ;-) Actually we're a little short on reviews generally, so I'd encourage anyone who hasn't taken a look yet to do so, code is the sandbox under /big_number/, docs are viewable online here: http://svn.boost.org/svn/boost/sandbox/big_number/libs/multiprecision/doc/h… Many thanks, John.

3 2

Trimming Dependencies (was Boost and exceptions)
by Daniel James 24 Jun '12

24 Jun '12

On 24 June 2012 01:55, Dave Abrahams <dave(a)boostpro.com> wrote: > > on Sat Jun 23 2012, Daniel James <dnljms-AT-gmail.com> wrote: > >> >> That's pretty crazy. Do you know if separating test dependencies would >> make much of a difference? > > They're already separated, along with documentation dependencies. You > *really* don't want to see the graph that includes the test dependencies > ;-) OK, I assumed from the dependencies on Test … [View More]

2 1

Boost and exceptions
by Dirk Ulrich 24 Jun '12

24 Jun '12

Dear all, when looking at Boost as a whole its obvious that it uses C++ exceptions to report exceptional conditions because its the C++ way of doing it and it has to interact with the C++ standard library. On the other hand it seems also obvious that some libraries (Boost.Units, Boost.MPL, etc.) do probably not use C++ exceptions at all since they are pure compile time libraries or provide services which do not have exceptional cases. I am working on a C++ based project which forbids the … [View More]

18 71

Boost's on the map
by John Maddock 23 Jun '12

23 Jun '12

Literally in this case: http://softwaremaniacs.org/media/alenacpp/cppmap-2012.png John.

4 3

Re: [boost] Boost and exceptions
by Brian Wood 23 Jun '12

23 Jun '12

John Maddock: > This actually looks compelling enough to me, that we should probably mandate > use of BOOST_THROW_EXCEPTION. Are you going to take away their library card if an author doesn't want to do this? ;) Cheers, Brian Wood Ebenezer Enterprises http://webEbenezer.net <http://webebenezer.net/>

1 0

Re: [boost] Boost and exceptions
by Brian Wood 23 Jun '12

23 Jun '12

Fabio Fracassi: > That is how modular development works, you let go of some control in > exchange for synergy effects and free added functionality. > Yes, it creates communication overhead but the win (for the users) is huge. I skipped Boost 1.49 and have been updating these results using Boost 1.50 -- http://webEbenezer.net/comparison.html<http://webebenezer.net/comparison.html> . I haven't noticed any performance improvements in the serialization library that's in Boost from … [View More]

1 0

Linked map
by Kannan R 23 Jun '12

23 Jun '12

Recently i wrote a json parser. I used stl map to store the json objects. Everything was fine except the order of the objects. Is it worth to build something in boost to have the map which provides an iterator to get the elements in same order? Please advise.

3 2

exception handling in multithreaded applications (was: RE: Boost and exceptions)
by Thomas Klimpel 22 Jun '12

22 Jun '12

Fabio Fracassi wrote: > Yes it is, because in reality boost exception solves problems for the > users of any library that uses it. When using boost exception I can > safely let exceptions escape threads and have them rethrown in the > starting thread, for instance. I would be interested to learn how you do this. With open-mp (and mpi), my current way to add exception handling code really adds much noise: bool cancel = false; #pragma omp parallel shared(cancel) { try { ... … [View More]

2 1

emulating concepts in C++11
by lcaminiti 22 Jun '12

22 Jun '12

Hello all, I was not able to find Boost.Generic source code (I asked Matt Calabrese but no reply): http://blip.tv/boostcon/boost-generic-concepts-without-concepts-5262126 Are you aware of any trick (e.g., the tricks used by Boost.Generic) to emulate concepts in C++11? Thanks. --Lorenzo -- View this message in context: http://boost.2283326.n4.nabble.com/boost-emulating-concepts-in-C-11-tp46317… Sent from the Boost - Dev mailing list archive at Nabble.com.

2 2

Still a monolithic library? Or a bunch of independent ones?
by hello world 21 Jun '12

21 Jun '12

Hello, It's been a few years since I didn't come around boost.org, and I was just wondering... Is boost still a monolithic library? or Is it a collection of separate libraries now? Or to state it another way: Is it ``easy'' to take only one library's files from the boost distribution and use it. Or do I have to carry everything around even If I'm using just one library? I understand that this must be library specific, but I'm just asking this to know what your general feel overall. Thanks.

3 2

Interest in a "breadth first" algorithm?
by Gary Powell 21 Jun '12

21 Jun '12

A while ago I needed to serialize and de-serialize a std::map and I realized that the only interface was begin(), end() which of course meant that re-creating this same map was the least efficient way possible, as all the elements were added in sorted order. Because I wrote them out using begin() -> end() So I wrote a breadth first template which takes a container, a template to use as the core of a queue, a template for the allocator, the container and a function to apply to the elements. … [View More]

4 4

Integrating CUDA nvcc into bjam
by jombi01821 21 Jun '12

21 Jun '12

I would like to know how to take an existing project that build with bjam and have it understand how to handle .cu CUDA files -- View this message in context: http://boost.2283326.n4.nabble.com/Integrating-CUDA-nvcc-into-bjam-tp463163… Sent from the Boost - Dev mailing list archive at Nabble.com.

1 0

[1.50] Is it too late for fixes?
by John Maddock 21 Jun '12

21 Jun '12

I have a trivial fix for 1.50 if it's not too late (missing include guards on a header), see https://svn.boost.org/trac/boost/ticket/7001 Is it too late now, suspect it is? Thanks, John.

1 0

[exception] gcc 4.7 non-virtual destructor warning
by Daniel Larimer 21 Jun '12

21 Jun '12

/usr/local/include/boost/checked_delete.hpp:34:5: warning: deleting object of polymorphic class type 'boost::error_info<boost::tag_original_exception_type, const std::type_info*>' which has non-virtual destructor might cause undefined behaviour [-Wdelete-non-virtual-dtor] Is there a reason why the destructor isn't virtual? This only shows up when I compile with -Wall, which I like to do because it catches many important errors. Unfortunately, if I have to filter out boost warnings it … [View More]

3 3

[release] merge request for test fix
by Jürgen Hunold 20 Jun '12

20 Jun '12

Hi, I would like to merge r78972 to the release branch. It fixes some test failures introduced by 78802 which renamed UTC_TIME to UTC_TIME_. Trunk tests have cycled for 2 days and the interprocress results start to turn green. Yours, Jürgen -- * Dipl.-Math. Jürgen Hunold ! * voice: ++49 4257 300 ! Fährstraße 1 * fax : ++49 4257 300 ! 31609 Balge/Sebbenhausen * jhunold(a)gmx.eu ! Germany

2 2

hex/unhex()?
by Olaf van der Spek 19 Jun '12

19 Jun '12

Hi, Does Boost have hex/unhex() that support std::string? I can't find them and I think they'd be quite handy to have. -- Olaf

7 35

[svn] post commit hooks broken
by Jürgen Hunold 19 Jun '12

19 Jun '12

Hi, the subversion post commit hooks seem to be broken. The last commit mail I got is Author: garcia Date: 2012-06-07 16:20:43 EDT (Thu, 07 Jun 2012) New Revision: 78856 and there habe been numerous commits since. I have also checked in a followoup to r78802 yesterday, which should have triggered an automated trac entry for #6940. But nothing happens. Can someone with enough karma please take a look at this? As a sidenote: The inofficial git mirror seems stalled, too. Yours, Jürgen -- … [View More]

2 2

[Locale] VC11 Regressions
by Joshua Boyce 18 Jun '12

18 Jun '12

I am currently porting some code to the VC11 compiler beta, and as part of that process I ran the unit tests on the libraries I use and noticed some failures in Boost.Locale under VC11 that are not present under VC10. Ones of the tests (test_winapi_collate) actually crashes (showing the WER dialog etc). Logs for comparison (tests were run on trunk): http://dl.dropbox.com/u/74751/cpp/boost/logs/locale-test-vc10-20120330-2143… http://dl.dropbox.com/u/74751/cpp/boost/logs/locale-test-vc11-… [View More]

4 11

Multiprecision vs. xint
by Phil Endecott 18 Jun '12

18 Jun '12

Dear All, I'd like to encourage people who are looking at the proposed Multiprecision library to remind themselves of the xint review last year. See e.g. http://thread.gmane.org/gmane.comp.lib.boost.devel/218624 (result) http://thread.gmane.org/gmane.comp.lib.boost.devel/215968 (my review) etc. etc. To what extent do we believe that this new library addresses the weaknesses of the last proposal? It would be great if Vladimir Prus, review manager for xint, could write a … [View More]

5 9