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[asio][thread] a new model for boost::asio (coroutine)
by 李慧霸 07 Jul '06

07 Jul '06

I have used the recent boost::asio library in my small project, I found it very difficult to correctly write the asynchronous code. So I tried another approach ---- a Half-Sync/Half-Async, I found it much better. The basic idea is very simple, utilize the coroutines(also called light weight threads, or user level threads) to handle multiple connections simultaneously and collaboratively. This approach has the advantange of simplicity in the Synchronous IO model, as well as the high performance in the Asynchronous IO model. Unfortunately, there isn't any coroutine support in boost::thread, and I had to make my experiment with the fiber support in ms windows. So I suggest coroutine be support. The benefit isn't only confined to boost::asio, in fact, it's an important way to describe algorithm flow, and many dynamic languages, both old and new, are supporting this feature. -------------- lihuiba 2006-07-05

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updated cvalarray
by Michael Tegtmeyer 06 Jul '06

06 Jul '06

I have updated the cvalarray tarball in the vault in response to comments. Changes include documentation fixes, minor bug fix, and additional test cases. See the changelog for specifics. Also in response to comments, I will add another document describing this particular implementation. Until then, highlights include: - expression templates for math operations - explicit assignment loop unrolling for small arrays - fundamental type recognition for memcpy for larger arrays Thanks for the comments. As I mentioned to some folks privately, I have no experience with VC++ so if anyone would care to try and compile a test case, I'd be grateful to hear about the experience. Thanks Mike

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Is there interest for iterator based conversion library?
by Alexander A Potocki 06 Jul '06

06 Jul '06

Hi boost community! I would like to propose my iterator based conversion library. It allows declaring and using transformations by following way: std::wstring utf16string(L”some sequence to convert”); typedef cvt::encoder<wchar_t, char> coder_t; coder_t coder = cvt::utf16() >> cvt::utf8(); That piece of code declares converter from wchar_t to char sequences and then instantiate such converter by utf16 to utf8 transformation. Then that converter instance can be used by following way: typedef cvt::convert_input_iterator<coder_t, std::wstring::const_iterator > it_t; - declaration of input iterator std::string result; std::copy( it_t(coder, utf16string.begin(), utf16string.end()), it_t(coder, utf16string.end(), utf16string.end()), std::back_inserter(result) ); Now we have utf8 encoded string in result container. That’s all. Library contains implementation for following transformations/algorithms: utf7, utf8, utf16(be/le), utf32(be, le), Unicode simple folding, base64, rc5(cipher/decipher). Library allows creating pipeline converters, e.g.: typedef cvt::encoder<char, char> coder_t; // char to char sequence transformation coder_t coder = cvt::utf7() >> cvt::utf16() >> cvt::utf8() / cvt::int8() >> cvt::rc5<32,12,8>(key) / cvt::int8() >> cvt::base64(); That expression defines pipeline transformation. Utf7 encoded sequence transforms to utf16 encoded sequence, then to utf8 encoded, then performs rc5 cipher with specified key, then performs base64 encoding. Library can be found at http://sourceforge.net/projects/trotter-cvt/ Alexander Potocki

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Re: [boost] Comment on string / unicode discussion
by Reece Dunn 06 Jul '06

06 Jul '06

Sean Parent wrote: > What we do need - are good standard algorithms which can be applied > to any string class. Agreed. This is where Boost.StringAlgorithms come in. What I am interested in is *efficient* codepage -> codepage conversion. For example, I may want to read a file in that is stored as 8-bit ASCII as UTF8. Likewise, I may want to take UTF8 data and save it as UTF16, MacRoman or some other encoding. What you need is an encoding -> UTF32 converter and a UTF32 -> encoding converter. Ideally, I would like each of these to be as efficient as possible. They should also be able to accept partial data. That is, if I am reading in a UTF8 file in blocks, it is possible to hit the middle of a character. This can be solved in a random access stream by seeking to the previous character, but this is not always possible. Consider: std::basic_ostringstream< uchar32_t > utf; utf.set_locale( utf8_to_utf32_cvt()); // not sure on exact code here std::string utf8 = some_utf8_data(); std::copy( utf8.begin(), utf8.end(), stream_inserter( utf )); The problem with this is that the stringstream type is uchar32_t, but has an *input* character type of char. The conversion mappings are of the form: n source characters -> m destination characters where these may be encoded byte sequences (e.g. UTF8), surrogate pairs (e.g. UTF16) or combining characters (e.g. a + umlaut). I am not sure how good locales are for this kind of functionality and also how good C++ streams are for this. However, it would be nice to have a stream interface (i.e. << and >>). - Reece _________________________________________________________________ Be one of the first to try Windows Live Mail. http://ideas.live.com/programpage.aspx?versionId=5d21c51a-b161-4314-9b0e-49…

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quan was [PQS]
by Andy Little 06 Jul '06

06 Jul '06

Hi, After all the interest in the PQS review, I have opted to rehouse the project on sourceforge and rename the project Quan. I am pleased to announce that the first release of Quan is now available. http://sourceforge.net/projects/quan/ There are many changes from pqs-3_1_x, based on the comments in the PQS review. See the quan-0_1_0 release notes on sourceforge for details: http://sourceforge.net/project/shownotes.php?release_id=429568&group_id=170… The project is also available via CVS: http://quan.cvs.sourceforge.net/quan/ Please also get in touch if you are interested in contributing to the project. regards Andy Little

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Re: [boost] Comment on string / unicode discussion
by Martin Bonner 06 Jul '06

06 Jul '06

Just one comment: From: Sean Parent > Consider - > > to_lower(first, last, output) How do you handle that with just a forward iterator? You need to read a whole word before you can decide whether "SS" should be "ß" or "ss" in the output. (I suppose you could read the word into an internal buffer - but that seems extreme). > such transformations can work with any encoding (you can uppercase > UTF-8 into UTF-32). They can't work in-situ (but I don't think > to_upper or to_lower really can work in-situ - certainly not in UTF-8 > and probably not in UTF-16, and I believe there are some multi- > character forms that even break in UTF-32...). It is ß -> SS that break in-situ conversion! -- Martin Bonner Martin.Bonner(a)Pitechnology.com Pi Technology, Milton Hall, Ely Road, Milton, Cambridge, CB4 6WZ, ENGLAND Tel: +44 (0)1223 203894

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(no subject)
by Sean Parent 06 Jul '06

06 Jul '06

> This is very close to what I have in mind. The main difference is that > the functions/algorithms in my mind take ranges instead of iterators. > Thus: > > to_lower(src, dest) > to_upper(src, dest) So long as you don't require ranges (or a pair of iterators makes a valid range and dest can still be an output iterator). That's fine - these should work on char* as well as container types. I don't know what kind of ranges you have for dest which allow dest to change size - seems a bit problematic. I want iterators that can handle the encoding transform. I want to be able to write items like the following: std::string s = get_some_utf_8_xml_data(); // Find the BOM character as a UTF-32 character utf_iterator_t i = std::find(utf_iterator_t(s.begin()), utf_iterator_t (s.end()), UL0x0000FEFF); assert(*i.base() == U0xEF); // base iterator points to start of UTF-8 character Sean > With these, I could make Fusion like wrappers that transform them into > something like: > > some_string s1 = to_lower(src); > some_string s2 = to_upper(src); > > where to_lower and to_upper return cheap views that are in and by > themselves valid strings/ranges. They are cheap because the actual > conversions/transformations are done on demand-- think lazy > evaluation. > So, like those done by expression template techniques, there are > no expensive temporaries when you perform seemingly expensive tasks > like: > > some_string s = f1(f2(f3(f4(src)))); > > And yes, because they are generic, those string algorithms can work > on any string type that satisfy some basic requirements. > > Regards, > > -- > Joel de Guzman > http://www.boost-consulting.com > http://spirit.sf.net

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Re: [boost] Exception lib?
by Sohail Somani 05 Jul '06

05 Jul '06

> -----Original Message----- > From: boost-bounces(a)lists.boost.org > [mailto:boost-bounces@lists.boost.org] On Behalf Of Emil Dotchevski > > Well for some people the only way to fix a const correctness related > > error is to remove the const. I can imagine people doing > all sorts of > > (wrong)casts. IMHO, I think the api should constrain that freedom > > seeing as there *is* only one right way to do it! > > Please let's keep this to the point. There are no const_casts in the > proposed Boost Exception library. If you think that the > dynamic_cast can be > avoided, I'm very much interested to hear how. If you think > the need for > dynamic_cast is a result of poor library design, I'm very > much interested to > hear about any improvement ideas. You're missing my point. I didn't say that dynamic_cast in this way is bad, nor did I say someone would use const_cast. I was only pointing out that there are those who will just do what they can to get it to look like it works. Restrict those people. Sohail

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[Boost-bugs] [ boost-Bugs-1517803 ] intel-win32 does not compile at all
by SourceForge.net 05 Jul '06

05 Jul '06

Bugs item #1517803, was opened at 2006-07-05 21:09 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=107586&aid=1517803&group_… Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: config Group: None Status: Open Resolution: None Priority: 5 Submitted By: jrp (godrick) Assigned to: John Maddock (johnmaddock) Summary: intel-win32 does not compile at all Initial Comment: boost>bjam "-sTOOLS=intel-win32" stage gives the sort of errors listed below with Intel C++ 9.1 ...failed vc-C++ bin\boost\libs\wave\build\boost_wave.dll\intel-win32 \release\th reading-multi\token_ids.obj... vc-C++ bin\boost\libs\wave\build\boost_wave.dll\intel- win32\release\threading-mu lti\wave_config_constant.obj '/Zm800' is not recognized as an internal or external command, operable program or batch file. /Zm800 -nologo /EHsc -c -DNDEBUG -DNDEBUG - DBOOST_ALL_DYN_LINK=1 /Ogity /O 2 /Gs /Ob2 /EHsc /GR /MD /Qwn5 /Qwd985 /Qwe556 - Qoption,c,--arg_dep_lookup /Qvc6 -DBOOST_NO_INTRINSIC_WCHAR_T - I"bin\boost\libs\wave\build" -I"D:\Projects\boost " -I"D:\Projects\boost" - Fo"bin\boost\libs\wave\build\boost_wave.dll\intel-win 32\release\threading-multi\wave_config_constant.obj" - Tp"D:\Projects\boost\libs\ wave\build\../src/wave_config_constant.cpp" ...failed vc-C++ bin\boost\libs\wave\build\boost_wave.dll\intel-win32 \release\th reading-multi\wave_config_constant.obj... vc-C++ bin\boost\libs\wave\build\boost_wave.dll\intel- win32\release\threading-mu lti\aq.obj '/Zm800' is not recognized as an internal or external command, operable program or batch file. /Zm800 -nologo /EHsc -c -DNDEBUG -DNDEBUG - DBOOST_ALL_DYN_LINK=1 /Ogity /O 2 /Gs /Ob2 /EHsc /GR /MD /Qwn5 /Qwd985 /Qwe556 - Qoption,c,--arg_dep_lookup /Qvc6 -DBOOST_NO_INTRINSIC_WCHAR_T - I"bin\boost\libs\wave\build" -I"D:\Projects\boost " -I"D:\Projects\boost" - Fo"bin\boost\libs\wave\build\boost_wave.dll\intel-win 32\release\threading-multi\aq.obj" - Tp"D:\Projects\boost\libs\wave\build\../src/ cpplexer/re2clex/aq.cpp" ...failed vc-C++ bin\boost\libs\wave\build\boost_wave.dll\intel-win32 \release\th reading-multi\aq.obj... vc-C++ bin\boost\libs\wave\build\boost_wave.dll\intel- win32\release\threading-mu lti\cpp_re.obj '/Zm800' is not recognized as an internal or external command, operable program or batch file. /Zm800 -nologo /EHsc -c -DNDEBUG -DNDEBUG - DBOOST_ALL_DYN_LINK=1 /Ogity /O 2 /Gs /Ob2 /EHsc /GR /MD /Qwn5 /Qwd985 /Qwe556 - Qoption,c,--arg_dep_lookup /Qvc6 -DBOOST_NO_INTRINSIC_WCHAR_T - I"bin\boost\libs\wave\build" -I"D:\Projects\boost " -I"D:\Projects\boost" - Fo"bin\boost\libs\wave\build\boost_wave.dll\intel-win 32\release\threading-multi\cpp_re.obj" - Tp"D:\Projects\boost\libs\wave\build\../ src/cpplexer/re2clex/cpp_re.cpp" ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=107586&aid=1517803&group_… Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Boost-bugs mailing list Boost-bugs(a)lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/boost-bugs

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Re: [boost] Exception lib?
by Sohail Somani 05 Jul '06

05 Jul '06

> -----Original Message----- > From: boost-bounces(a)lists.boost.org > [mailto:boost-bounces@lists.boost.org] On Behalf Of Dean > Michael Berris > Sent: Wednesday, July 05, 2006 11:07 AM > To: boost(a)lists.boost.org > Subject: Re: [boost] Exception lib? > > It's probably a personal issue against the use of dynamic_cast<> or > static_cast<> and even const_cast<> because IMHO it makes code > terribly un-readable and even seem "hackish". It's my personal opinion > that whenever you need to resort to casting in client code, then that > means the design of the solution isn't as elegant or as well thought > out as it could be. Not to mention that the client can and will do it wrong.

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