There is a problem in date_time library with function to_iso_string(date) when a global locale is set. The library creates a stream to output year which applies global locale formatting including thousand separators, i.e. "2,002". Look at this test: Added to testtime_formatters.cpp: const std::locale& original_locale(std::locale::global(std::locale("en_US.utf8"))); check("simple+loc: [" + t1_result + "]==[" + to_simple_string(t1) + "]", t1_result == to_simple_string(t1)); check("iso+loc: [" + iso_result + "]==[" + to_iso_string(t1) + "]", iso_result == to_iso_string(t1)); check("iso ext+loc: [" + iso_ext_result + "]==[" + to_iso_extended_string(t1) + "]", iso_ext_result == to_iso_extended_string(t1)); std::locale::global(original_locale); results in: execute-test ../../../bin/boost/libs/date_time/test/testtime_formatters.test/gcc/debug/te sttime_formatters.run ====== BEGIN OUTPUT ====== 2002-Jan-01 01:02:03 ... FAIL :: simple+loc: [2002-Jan-01 01:02:03]==[2,002-Jan-01 01:02:03] FAIL :: iso+loc: [20020101T010203]==[2,0020101T010203] FAIL :: iso ext+loc: [2002-01-01T01:02:03]==[2,002-01-01T01:02:03] ... 14 Tests Executed: 3 FAILURES As email at the end suggests this problem is known for some time. Are there any plans to fix it? If I may suggest, the fix could be to imbue the stream with classic locale for the purpose of year output: date_formatting.hpp template<class ymd_type, class format_type, class charT=char> class ymd_formatter { public: static std::basic_string<charT> ymd_to_string(ymd_type ymd) { typedef typename ymd_type::month_type month_type; std::basic_ostringstream<charT> ss; ss.imbue(std::locale::classic()); // <--- The fix ss << ymd.year; ss.imbue(std::locale::locale()); // <--- The fix if (format_type::has_date_sep_chars()) { ss << format_type::month_sep_char(); } //this name is a bit ugly, oh well.... month_formatter<month_type,format_type,charT>::format_month(ymd.month,ss); if (format_type::has_date_sep_chars()) { ss << format_type::day_sep_char(); } ss << std::setw(2) << std::setfill(ss.widen('0')) << ymd.day; return ss.str(); } }; Thanks, Andrew

From: Jeff Garland <jeff <at> crystalclearsoftware.com> Subject: Re: date serialization fails with non-standard locales Newsgroups: gmane.comp.lib.boost.user Date: 2005-05-28 14:39:38 GMT (1 year, 39 weeks, 4 days and 15 minutes ago)

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I'm not sure if this is a bug or if I'm misusing the

On Sat, 28 May 2005 02:10:02 +0200, Paolo Coletta wrote library. It seems

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that serializing boost::posix_time_ptime fails when using non-standard locale (Windows Xp OS - vc 7.1 compiler - boost updated from CVS few days ago).

As an example, try adding

std::locale::global( std::locale( "en" ) );

as the first line of the testtime_serialize.cpp; this causes the test to fail when doing

ia >> pt2;

I tried to understand what was happening, and it seems to me that the problem is in keeping into account locale when serializing, while ignoring it while unserializing. In greg_serialize.hpp to_iso_string(d) may generate something like "2,0050527"; the method from_undelimited_string(ds) used to load the serialized date, expects a 4,2,2 format.

It looks like the problem is that the stream output is including a thousands seperator when it shouldn't. The serialization should be 20050527 with no number seperators. So it appears that we cannot depend on the stream not using the thousands separtor in date_time/date_formatting.hpp (line 81) where the year is actully output:

std::basic_ostringstream<charT> ss; ss << ymd.year;

We'll look into fixing this...

Jeff