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Boost DateTime package question
by Mohnish Kodnani 10 Jul '08

10 Jul '08

Hi All, I have a question regarding the boost DateTime package. In our application we have to support storing time from various time zone in UTC and we need to know DST of various timezones. We are currently using standard C runtime libraries for this purpose on various platforms like windows , linux, aix, hpux. My question, Recently there has been a need to store dates prior to epoch in our system and this causes problems since none of the standard C runtime libraries support dates prior to EPOCH. We are also interested in DST settings prior to EPOCH, since in our experiments it looks like Java knows DST till 1942 or in its vicinity, however C only deals with dates after epoch. Our server is in C++ and client in Java, so we have issues here when client sends a date prior to 1942 and we have to store its UTC value, we cannot do this since C runtime mktime like functions dont work. Does Boost DateTime package provide this functionality, if not is that in the plans. >From what I read so far it looks like this package does not have this functionality, but has the functionality to create our own rules, however this is difficult considering all countries around the world, it would be good if we had something similar to C runtime. Please let me know. thanks Mohnish

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[constrained_value] Formal review request
by Robert Kawulak 10 Jul '08

10 Jul '08

Dear Boosters, I'm glad to say the Boost Constrained Value library is finally ready for a formal review. To remind what this library is about, an excerpt from the motivation section of the documentation is attached at the bottom of this message. Jeff, you volunteered to be the review manager - is your proposition still up to date? If so, I'd be thankful if you could do the work. ;-) The code and documentation can be downloaded here: http://rk.go.pl/f/constrained_value.zip The documentation is also available online here: http://rk.go.pl/r/constrained_value The only thing that's missing is test programs - I will try to add them during/after the review. The changes made since previous version: - rewritten the documentation at some points and added tutorial, - no more value generators - direct types or MPL integral constants are used instead, - bounded types use bounds exclusion instead of inclusion (so bounds are included by default in all cases), - changed order and default values of some of template parameters, - removed throw_verbose_exception error policy, - made other minor fixes and improvements. As always, feedback is welcome. Best regards, Robert Kawulak FROM THE MOTIVATION SECTION OF THE DOCUMENTATION: The Boost Constrained Value library contains class templates useful for creating constrained objects. A simple example is an object representing an hour of a day, for which only integers from the range [0, 23] are valid values: bounded_int<int, 0, 23>::type hour; hour = 20; // OK hour = 26; // exception! Behavior in case of assignment of an invalid value can be customized. For instance, instead of throwing an exception as in the example above, the value may be adjusted to meet the constraint: wrapping_int<int, 0, 255>::type buffer_index; buffer_index = 257; // OK: adjusts the value to fit in the range by wrapping it assert( buffer_index == 1 ); The library doesn't focus only on bounded objects as in the examples above -- virtually any constraint can be imposed by using a predicate: // constraint (a predicate) struct is_odd { bool operator () (int i) const { return (i % 2) != 0; } }; // and the usage is as simple as: constrained<int, is_odd> odd_int = 1; odd_int += 2; // OK ++odd_int; // exception! The library has a policy-based design to allow for flexibility in defining constraints and behavior in case of assignment of invalid values. Policies may be configured at compile-time for maximum efficiency or may be changeable at runtime if such dynamic functionality is needed.

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[test][sun-5.7 -5.8][trunk] regressions for Boost.Test starting at revision 47170
by JOAQUIN M. LOPEZ MUÑOZ 10 Jul '08

10 Jul '08

Hello, Recent updates to the trunk version of Boost.Test have resulted in a massive number of regressions for Sun 57 and 5.8, as shown for instance in: http://tinyurl.com/5lm7ha http://tinyurl.com/66qcze The error message is "../boost/test/utils/iterator/input_iterator_facade.hpp", line 56: Error: Multiple declaration for input_iterator_facade. After examining the updates to Boost.Test in the last days I think I found the change that's causing the regressions: http://svn.boost.org/trac/boost/changeset/47170/trunk/boost/test The change in line 26 of boost/test/impl/unit_test_main.ipp causes the header <boost/test/utils/iterator/token_iterator.hpp> to be included where previously that was not the case. This in turns includes <boost/test/utils/iterator/input_iterator_facade.hpp>, which contains the following problematic code (for Sun 5.7-8) around line 25: #if defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS) || BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551)) public: #else template <class I, class V, class R, class TC> friend class input_iterator_facade; #endif This perfectly correct friend declaration is not processed properly by Sun 5.7 and 5.8 hence the error. May I ask that the problem be fixed by applying either one of the following? 1. Add a workaround for Sun 5.7-8 at line 35 of boost/test/utils/iterator/input_iterator_facade.hpp 2. Add a !workaround for Sun 5.7-8 at line 26 of boost/test/impl/unit_test_main.ipp Thank you! Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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[inspect] A few issues in non-ASCII checker
by Gennaro Prota 10 Jul '08

10 Jul '08

Hi, I had a summary look at the changes made to Boost.Inspect (since I last saw it) and noticed a few issues: * the "*A*" marker is used either for broken links, invalid urls etc. *and* non-ASCII chars * "non-ASCII" itself looks like a misleading name: see the string gPunct, defined in ascii_check.cpp * non portable (though widely portable :-)) code: if ( c >= 'a' && c <= 'z' ) return false; if ( c >= 'A' && c <= 'Z' ) return false; if ( c >= '0' && c <= '9' ) return false; If there aren't problems with standard library support I'd suggest replacing the above with if ( std::isalnum( static_cast< int >( c ), std::locale::classic() ) ) Similarly for the subsequent isspace-like tests * again in ascii_check.cpp there's some scaffolding to get a line number from a file position; this is needed in other inspector classes as well, and is done much differently. I think it is worth unifying this part and make it available in one place -- Genny

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public beta test ?
by Ruediger Berlich 10 Jul '08

10 Jul '08

Hi there, I'd like to suggest a public beta test as part of the release procedure. >From what I can see, while the trunk version is available to everybody, there is no formal call for external testing. But this would increase visibility of Boost and would likely reveal a number of additional bugs. Best, Ruediger

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a little imperfection in options_description.cpp example (program options)
by Guido Ziliotti 10 Jul '08

10 Jul '08

// A helper function to simplify the main part. template<class T> ostream& operator<<(ostream& os, const vector<T>& v) { copy(v.begin(), v.end(), ostream_iterator<T>(cout, " ")); /* this is line 21 */ return os; } SHOULD BE REPLACED WITH // A helper function to simplify the main part. template<class T> ostream& operator<<(ostream& os, const vector<T>& v) { copy(v.begin(), v.end(), ostream_iterator<T>(os, " ")); /* this is line 21: "os" replaces "cout" */ return os; }

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[1.36.0] Unmerged SVN Properties
by Beman Dawes 10 Jul '08

10 Jul '08

There are a whole bunch (see below) of messages from the unmerged changes analysis that look like this: Property changes on: tr1/tr1/valarray ___________________________________________________________________ Name: svn:eol-style + native Name: svn:mime-type + text/plain I guess these need to be merged from trunk to branches/release like any other change. --Beman Here is the full list: Property changes on: archive/detail/polymorphic_iarchive_route.hpp Property changes on: archive/detail/polymorphic_oarchive_route.hpp Property changes on: archive/xml_archive_exception.hpp Property changes on: compatibility/cpp_c_headers/cassert Property changes on: compatibility/cpp_c_headers/cctype Property changes on: compatibility/cpp_c_headers/cerrno Property changes on: compatibility/cpp_c_headers/cfloat Property changes on: compatibility/cpp_c_headers/climits Property changes on: compatibility/cpp_c_headers/clocale Property changes on: compatibility/cpp_c_headers/cmath Property changes on: compatibility/cpp_c_headers/csetjmp Property changes on: compatibility/cpp_c_headers/csignal Property changes on: compatibility/cpp_c_headers/cstdarg Property changes on: compatibility/cpp_c_headers/cstddef Property changes on: compatibility/cpp_c_headers/cstdio Property changes on: compatibility/cpp_c_headers/cstdlib Property changes on: compatibility/cpp_c_headers/cstring Property changes on: compatibility/cpp_c_headers/ctime Property changes on: compatibility/cpp_c_headers/cwchar Property changes on: compatibility/cpp_c_headers/cwctype Property changes on: config/warning_disable.hpp Property changes on: detail/lightweight_thread.hpp Property changes on: detail/sp_convertible.hpp Property changes on: detail/sp_counted_base_spin.hpp Property changes on: detail/spinlock.hpp Property changes on: detail/spinlock_gcc_arm.hpp Property changes on: detail/spinlock_nt.hpp Property changes on: detail/spinlock_pool.hpp Property changes on: detail/spinlock_pt.hpp Property changes on: detail/spinlock_sync.hpp Property changes on: detail/spinlock_w32.hpp Property changes on: detail/yield_k.hpp Property changes on: graph/edmonds_karp_max_flow.hpp Property changes on: graph/r_c_shortest_paths.hpp Property changes on: iostreams/detail/execute.hpp Property changes on: iostreams/detail/file_handle.hpp Property changes on: iostreams/detail/file_times.hpp Property changes on: iostreams/detail/functional.hpp Property changes on: iostreams/detail/path.hpp Property changes on: iostreams/filter/grep.hpp Property changes on: make_shared.hpp Property changes on: math/distributions/detail/generic_mode.hpp Property changes on: math/distributions/detail/generic_quantile.hpp Property changes on: math/distributions/non_central_beta.hpp Property changes on: math/distributions/non_central_chi_squared.hpp Property changes on: math/distributions/non_central_f.hpp Property changes on: math/distributions/non_central_t.hpp Property changes on: math/special_functions/detail/lanczos_sse2.hpp Property changes on: math/special_functions/detail/round_fwd.hpp Property changes on: math/special_functions/expint.hpp Property changes on: math/special_functions/modf.hpp Property changes on: math/special_functions/next.hpp Property changes on: math/special_functions/pow.hpp Property changes on: math/special_functions/round.hpp Property changes on: math/special_functions/trunc.hpp Property changes on: math/special_functions/zeta.hpp Property changes on: math/tr1.hpp Property changes on: memory_order.hpp Property changes on: pool/detail/for.m4 Property changes on: pool/detail/pool_construct.inc Property changes on: pool/detail/pool_construct.m4 Property changes on: pool/detail/pool_construct_simple.inc Property changes on: pool/detail/pool_construct_simple.m4 Property changes on: property_tree/detail/exceptions_implementation.hpp Property changes on: property_tree/detail/file_parser_error.hpp Property changes on: property_tree/detail/info_parser_error.hpp Property changes on: property_tree/detail/info_parser_read.hpp Property changes on: property_tree/detail/info_parser_utils.hpp Property changes on: property_tree/detail/info_parser_write.hpp Property changes on: property_tree/detail/info_parser_writer_settings.hpp Property changes on: property_tree/detail/json_parser_error.hpp Property changes on: property_tree/detail/json_parser_read.hpp Property changes on: property_tree/detail/json_parser_write.hpp Property changes on: property_tree/detail/path_implementation.hpp Property changes on: property_tree/detail/ptree_implementation.hpp Property changes on: property_tree/detail/ptree_utils.hpp Property changes on: property_tree/detail/pugxml.hpp Property changes on: property_tree/detail/rapidxml.hpp Property changes on: property_tree/detail/translator_implementation.hpp Property changes on: property_tree/detail/xml_parser_error.hpp Property changes on: property_tree/detail/xml_parser_flags.hpp Property changes on: property_tree/detail/xml_parser_read_pugixml.hpp Property changes on: property_tree/detail/xml_parser_read_pugxml.hpp Property changes on: property_tree/detail/xml_parser_read_rapidxml.hpp Property changes on: property_tree/detail/xml_parser_read_spirit.hpp Property changes on: property_tree/detail/xml_parser_read_tinyxml.hpp Property changes on: property_tree/detail/xml_parser_utils.hpp Property changes on: property_tree/detail/xml_parser_write.hpp Property changes on: property_tree/detail/xml_parser_writer_settings.hpp Property changes on: property_tree/info_parser.hpp Property changes on: property_tree/ini_parser.hpp Property changes on: property_tree/json_parser.hpp Property changes on: property_tree/ptree.hpp Property changes on: property_tree/ptree_fwd.hpp Property changes on: property_tree/ptree_serialization.hpp Property changes on: property_tree/xml_parser.hpp Property changes on: serialization/assume_abstract.hpp Property changes on: serialization/factory.hpp Property changes on: serialization/singleton.hpp Property changes on: serialization/vector_134.hpp Property changes on: statechart/detail/reaction_dispatcher.hpp Property changes on: swap.hpp Property changes on: test/utils/lazy_ostream.hpp Property changes on: tr1/tr1/algorithm Property changes on: tr1/tr1/array Property changes on: tr1/tr1/bitset Property changes on: tr1/tr1/complex Property changes on: tr1/tr1/deque Property changes on: tr1/tr1/exception Property changes on: tr1/tr1/fstream Property changes on: tr1/tr1/functional Property changes on: tr1/tr1/iomanip Property changes on: tr1/tr1/ios Property changes on: tr1/tr1/iostream Property changes on: tr1/tr1/istream Property changes on: tr1/tr1/iterator Property changes on: tr1/tr1/limits Property changes on: tr1/tr1/list Property changes on: tr1/tr1/locale Property changes on: tr1/tr1/map Property changes on: tr1/tr1/memory Property changes on: tr1/tr1/new Property changes on: tr1/tr1/numeric Property changes on: tr1/tr1/ostream Property changes on: tr1/tr1/queue Property changes on: tr1/tr1/random Property changes on: tr1/tr1/regex Property changes on: tr1/tr1/set Property changes on: tr1/tr1/sstream Property changes on: tr1/tr1/stack Property changes on: tr1/tr1/stdexcept Property changes on: tr1/tr1/streambuf Property changes on: tr1/tr1/string Property changes on: tr1/tr1/strstream Property changes on: tr1/tr1/tuple Property changes on: tr1/tr1/type_traits Property changes on: tr1/tr1/typeinfo Property changes on: tr1/tr1/utility Property changes on: tr1/tr1/valarray Property changes on: tr1/tr1/vector Property changes on: utility/swap.hpp

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[extension] Problem with reference types
by Robert Dailey 10 Jul '08

10 Jul '08

I have the following exported factory function in a DLL I'm building on Windows: extern "C" void BOOST_EXTENSION_EXPORT_DECL export_aspects( boost::extensions::factory_map& fm ) { using namespace vfx::aspects; using namespace vfx::messenger; fm.get<Aspect, MessageReader&, unsigned int>()[0].set<Appearance>(); fm.get<Aspect, MessageReader&, unsigned int>()[1].set<Health>(); } As you can see, I am specifying that each class accepts a single construction parameter- a reference to a MessageReader object. However, this isn't compiling because I don't think that it likes reference types. How can I specify that the constructor takes a reference? boost::ref? I would post the compiler warnings & errors I'm getting, however they're exceedingly large. Most of the warnings and errors are coming from std::map, basically complaining that it's trying to create a map of reference types, which can't possibly work. Help is appreciated. As an unrelated note, I would really like to see the template parameters cleaned up. There's at least 5 places I've had to redundantly specify the same 3 template parameters (like in the example above). I already brought this up in another thread, but I can't tell you how important it is. If I ever change the number of construction parameters my Appearance or Health classes take (mapped above), I will have to shift through 5 or more files simply to adjust all of the template parameters to make everything compile.

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[asio] std::ostream request_stream
by simonvifr＠voila.fr 09 Jul '08

09 Jul '08

Good morning, In the examples that illustrate the use of Boost.Asio in more complex applications, there is the "boost_asio/example/http/client/sync_client.cpp" example. In this example, the following code is written : boost::asio::streambuf request; std::ostream request_stream(&request); request_stream << "GET " << argv[2] << " HTTP/1.0\r\n"; request_stream << "Host: " << argv[1] << "\r\n"; request_stream << "Accept: */*\r\n"; request_stream << "Connection: close\r\n\r\n"; I would like to use the POST method with parameters instead of GET method, and to set the "Content-Type" property. But I do not how to do. Could you tell me more about using the POST method and setting the "Content-Type" property ? Could you also tell me where I can find documentation about it ? Thank you for your response, Regards. ____________________________________________________ Sur le mail Voila, vous pouvez personnaliser l’anti-spam ! http://mail.voila.fr

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An elegant way to initialize an instance of boost::any with a C-style string constant
by Ferdinand Prantl 09 Jul '08

09 Jul '08

Hello, I would like to improve usage of boost::any with text (char*) constants. This would be the goal: boost::any foo("foo"); boost::any bar; bar = "bar"; Currently the compiler (MSVC 2008 in my case) complains about it: ...\boost\any.hpp(117) : error C2536: 'boost::any::holder< ValueType>::boost::any::holder<ValueType>::held' : cannot specify explicit initializer for arrays There are more ways to make it compiled, all of them either with an extra cast or object construction: boost::any foo(static_cast<const char *>("foo")); boost::any foo((const char *) "foo"); boost::any foo(std::string("foo")); Supposing there is no way to persuade the compiler to consider the constant not to be an array but just a pointer I would suggest adding support for arrays to boost::any. I am sorry if it has been discussed already. I found just one thread without a conclusion (http://lists.boost.org/Archives/boost/2003/01/43460.php) I asked about it in boost.users and got a nice proposal from Niels Dekker (http://thread.gmane.org/gmane.comp.lib.boost.user/37189/focus=37414) I replaced the member "held" in holder<> by a wrapper specialized for arrays: template<typename ValueType> struct wrapper { ValueType data; explicit wrapper(const ValueType & value) : data(value) {} }; template<typename ElementType, std::size_t NumberOfElements> struct wrapper<ElementType[NumberOfElements]> { typename remove_const<ElementType>::type data[NumberOfElements]; explicit wrapper(const ElementType (& value)[NumberOfElements]) { std::copy(value, value + NumberOfElements, data); } }; A new constructor in boost::any makes use of it: template<typename ElementType, std::size_t NumberOfElements> any(const ElementType (& value)[NumberOfElements]) : content(new holder<ElementType[NumberOfElements]>(value)) {} This solution is more complicated but it makes the instance of boost::any own the copy of array just like its for scalar objects. Alternatively, instead of wrapping a copy of the array, I could store just a pointer to it without any other changes in bost::any (I want to use just constants in my example): template<typename ElementType, std::size_t NumberOfElements> any(const ElementType (& value)[NumberOfElements]) : content(new holder<const ElementType*>(value)) {} I am attaching a patch to any.hpp from boost 1.35.0. I could provide a test for it too. What do you think about it? Shall I create a feature request for it? Thank you, Ferda

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