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RE: [boost] Re: Date-Time
by Powell, Gary 14 Apr '04

14 Apr '04

>Bob Bell wrote: >The interpretation that makes sense to me is: adding one month means the >same day of the next month, unless the date's not valid, in which case I >expect moving backwards to the latest date of said month. That's what >humans do when you say "next month", so I would think anything else >would be surprising. That would surprise me as well. date = January 30; add_month(date); add_month(date); date == March 30 ? Not March 28/29 No? Which means of course a lot of state has to be held by date, because otherwise February does rounding. As in the number of days until the end of the month. Yours, -Gary-

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Date-Time
by Val Samko 14 Apr '04

14 Apr '04

I did not find any functions in Date-Time library to add a number of months to a given day, or to obtain the last/first day of the month. I mean something like date add_month(const date&, int month_count); date first_date_of_month(const date&); date last_date_of_month(const date&); I understand that I can use the month_iterator instead of add_month, and end_of_month_day instead of last_date_of_month, but since the functionality I described is heavily used in some applications (accounting for instance), it would be much simpler just to call add_month, ... functions. Is there any particular reason why they are not provided? Val Samko http://val.digiways.com

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FSM offtopic question
by Erdei Andras 14 Apr '04

14 Apr '04

can someone suggest a free, preferably windoze tool for creating graphics represantion of FSMs ? something using an editable format, but allowing GIF/BMP/whatever export for documentation would be nice. tia andras

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[serialization] all wide tests were failing because...
by Vladimir Prus 14 Apr '04

14 Apr '04

Robert, if you recall, all wide archive tests were failing for me. They still failed with #18, and now I finally (after quite some debugging) know why. The error I was getting was: Exception in "call_test_main": std::length_error: basic_string::reserve It occured even on test_vector, which is fairly simple. The generated data contained this: 22 boost::serialization .... note that this was for wide archive, where the data should have being in UCS-4 encoding, i.e. ('2' <zero> <zero> <zero> '2' ...) The reason, once found, is simple: { test_ostream os(testfile, TEST_STREAM_FLAGS); test_oarchive oa(os); } You change codecvt in archive constructors and the archive also has locale saver. The destructor for archive is called *before* destructor for 'os'. At this time, codecvt is switched back, right? So, when destructor of 'os' calls 'close' which flushes the data, you're using default codecvt. If I add explicit 'os.close()' after writing to archive, the written data is correct. What this means is that destructor of archive *really should* call 'flush' on the stream. After I've made basic_text_oprimitive's destructor to flush stream: template<class OStream> basic_text_oprimitive<OStream>::~basic_text_oprimitive(){ os.flush(); } The test_vector passed with wide stream. I'm rerunning other tests now. In fact, I'm getting suspicious about changing codecvt at all. I suppose that if somebody is using wide streams, he already deals with encoding somehow, so why serialization library should try to second-guess the user? - Volodya

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Re: [boost] Serialization. Pointer to constant object.
by Robert Ramey 14 Apr '04

14 Apr '04

Alexey Nikitin wrote: ... >void f3(A const* a, text_oarchive& oa) >{ > oa << a; >} >Why compiled function f1 and f2 but not f3 ? Good point. I have a fix - but it won't work for compilers that don't support Partial Template Specialization. I haven't been able to find a more general fix. Robert Ramey

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[program_options] Unicode support
by Vladimir Prus 14 Apr '04

14 Apr '04

Hello, it seems that Unicode support is the last issue that should be addressed before the library can be added to CVS. Since the issue is somewhat tricky, I'd appreciate some comments before I start coding. The initial description of the approach I plan is at http://zigzag.cs.msu.su:7813/program_options/html/program_options.design.ht… or http://zigzag.cs.msu.su/~ghost/program_options/html/program_options.design.… So summarize the document, user would be able to pass wchar_t** to the parse_command_line function. If specific option needs unicode, this can be specified like this: ("email", unicode::value<Email>(), "email address") I believe the change will be mostly transparent and won't affect ascii usage. All options are very welcome! TIA, Volodya

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question regarding basic_stream::imbue
by Robert Ramey 14 Apr '04

14 Apr '04

I have a simple question regarding basic_stream::imbue(locale &) Can it be applied after a file is opened? The state saver libray seems to suggest that it can. Some information suggests that it can if the file is position at the start. Experience with dinkumware and STLport suggests that it can't. If it can't what's the best way to work around it? Robert Ramey

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[serialization] utf8 test glitch
by Vladimir Prus 14 Apr '04

14 Apr '04

Robert, to make utf8 test pass, I had to apply the attached patch. Seems like there was a typo which manifected itself only on 4-bit wchar_t -- one of the trailing bytes did not have the high bit set, so the facet returned an error. - Volodya

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Re:[boost] Serialization #18
by Robert Ramey 14 Apr '04

14 Apr '04

Alexey Nikitin wrote: >I think it is not good idea to use "using namespace ...;" in header files. I agree - I'll fix it. Robert Ramey

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circular_buffer question
by Neal D. Becker 14 Apr '04

14 Apr '04

I'm looking at circular_buffer. It appears to me that operator[] uses "add", and that "add" only allows a positive value of offset? It is not difficult to allow arbitrary values, and this is very useful. if "position" is the current "m_first" and "allocated" is the allocated buffer size, the index could be calculated: int index (int offset) const { int x = (offset + position) % int(allocated); if (x >= 0) return x; else return x + allocated; }

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