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program_options problem on platforms with incomplete wchar_t
by Harri Pasanen 15 Sep '04

15 Sep '04

Hello, Looking at program_options headers, it does not appear to guard against BOOST_NO_STD_WSTRING being defined? This poses a problem when using gcc on platforms such as Solaris, HP-UX, as functions like std::codecvt<wchar_t, char, __mbstate_t>::do_length(...) are not defined in the libstdc++. Is this a know problem, should I come up with a patch, or what? Regards, Harri Pasanen This message, including any attachments, is intended only for the person(s) to whom it is addressed. If you received it in error, please let us know and delete the message from your system. This message may be confidential and may fall under the duty of non-disclosure. Any use by others than the intended addressee is prohibited. Trema shall not be liable for any damage related to the electronic transmission of this message, such as failure or delay of its delivery, interception or manipulation by third parties, or transmission of viruses or other malicious code. This message, including any attachments, is intended only for the person(s) to whom it is addressed. If you received it in error, please let us know and delete the message from your system. This message may be confidential and may fall under the duty of non-disclosure. Any use by others than the intended addressee is prohibited. Trema shall not be liable for any damage related to the electronic transmission of this message, such as failure or delay of its delivery, interception or manipulation by third parties, or transmission of viruses or other malicious code.

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bjam help...
by John Torjo 15 Sep '04

15 Sep '04

How do I set bjam to print (eventually to a file) all the commands it executes? I'm trying to configure gcc, and I don't know what I do wrong:( Best, John -- John Torjo -- john(a)torjo.com Contributing editor, C/C++ Users Journal -- "Win32 GUI Generics" -- generics & GUI do mix, after all -- http://www.torjo.com/win32gui/ -- v1.4.0 - save_dlg - true binding of your data to UI controls! + easily add validation rules (win32gui/examples/smart_dlg)

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RE: [boost] Formal review of "Output Formatters" library begins today
by Reece Dunn 14 Sep '04

14 Sep '04

Paul A Bristow wrote: >| [mailto:boost-bounces@lists.boost.org] On Behalf Of Reece Dunn >| > "Boost prefers clarity to curtness". >| >| I have been giving this some thought. What I am looking at at >| the moment is >| something like: >| >| std::pair >| < >| std::pair< int, std::vector< char > >, >| std::list< boost::math::quaternion< float > > >| > mct; > >Which leaves me puzzling what on earth mct can be short for ! >myVeryContrivedContainerType? > >Is this a complex demo assemblage? Yes. It was to give an example of the new (planned) naming scheme to output mct [my_complex_type]. >| namespace io = boost::io; >| namespace fmt = boost::io::format; > >using boost::io::format; > >would allow you to replace fmt with format? Which is much easier to >understand, >especially for those for whom english is not their first language? I would prefer to use a namespace alias where possible as I dislike unnecessarily polluting the global namespace. As to namespace format = boost::io::format; vs namespace fmt = boost::io::format; you can see that these are aliases for "boost::io::format", just like namespace fs = boost::filesystem; As long as it is put at the top of the code examples/tests and put in the documentation introdution at the beginning, clearly stating that "fmt" is a namespace alias for "boost::io::format" I don't see it being a problem. The problem with the current implementation naming scheme is that it uses Xfmt consistently and most importantly, *the user has no control over this*. Feel free in your code to use: namespace format = boost::io::format; or equivalent. Is there a concensus for/against the use of the shorter fmt::basic(), etc. in the docs and code? Dave? John? >Have I commented this correctly (and informatively)? Yes. Although I am not sure of the behaviour of using on a namespace name (don't you need a using namespace or a namespace alias?) >| std::cout << io::object( mct, >| fmt::pair >| ( >| fmt::pair( fmt::basic(), fmt::container()), // basic used for >int, container is a vector. >| fmt::container( fmt::nary()) // container is list, and n in the >nary is 4 for a quaternion. >| ) >| ); > > >| With io::delimiter holding one of the delimiter values. >| io::wrapped_delimiter will replace io::openclose_formatter in holding >open/close delimiter pairs > >why wrappED? io::wrapper? ({} [] ... The io::wrapped_delimiter above is a holder for open and closing pairs, so io::wrapper_delimiter doesn't seem syntactically correct. Maybe io::wrapp*ing*_delimiters? >| and io::sequence_delimiter replaces io::formatter. > >io::separator? , | ... Maybe io::sequence_delimiters. This is because it contains open/close *and* separator delimiters, since it is controlling how a sequence type is rendered. >(Of course, if English spelling made any sense whatever, it would be >separater - but it hasn't got to be the premier language by being phonetic, >consistent and logical, has it?) Causing me a great deal of confusion (even being a native English speaker!) >Paul > >PS >/rubbing_it_in_mode on > >some filenames have the spelling mistake too ;-) >This may confuse some using search later. Doh! >/rubbing_it_in_mode off >and finally > > std::cout << boost::io::formatob( vec ).format( "{ ", " }" ); ><<<<<<<<<<< >isn't this missing a ':' separator??? > // output: { 1 : 2 : 3 } Thorsten spotted this as well. I have updated the docs to: // output: { 1, 2, 3 } Thanks, Reece _________________________________________________________________ Stay in touch with absent friends - get MSN Messenger http://www.msn.co.uk/messenger

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bgl question: in which namespace to put the functions
by Andreas Fabri 14 Sep '04

14 Sep '04

Hello, Developping code so that BGL algorithms can run on the vertices and edges of CGAL triangulations, I am wondering if there are rules or recommendations for in which namespace the functions source, target, vertices, out_edges ... shall go. In boost, because it is boostish code, or in CGAL, because that is the namespace where the triangulation lives in? thank's in advance, andreas

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any interest in Boost Unification and Backtracking library (UBL)?
by G. Wang 14 Sep '04

14 Sep '04

Hi, all, Unification and backtracking are the two key concepts of Prolog language. Prolog language is one of the preferred ways to develop "intelligent" software. I am wondering how many people here are interested in a Boost Unification and Backtracking Library (UBL). UBL will implement the unification and backtracking feature with the help of both preprocessor meta-programming (Boost Preprocessor library) and template meta-programming (MPL). With UBL, you will define Prolog-like predicates right inside your C++ code. ========== Why do we need it? =========================== 1. a C++ and Prolog combined solution may not be convenient. You need to write a lot of wrapper code to allow bi-directional communications between Prolog code and C++ code. Standard Prolog is not an Object Oriented Programming Language. As such, you need to write even more code to allow Prolog to access C++ class instances. Worse yet, each prolog implementation has its own way to interface with foreign languages. So your wrapper code most likely would not be portable to other Prolog implementations. 2. Unlike C++, Prolog is not strong-typed. Folks in the C++ land too long may not like anything that is not strong-typed. 3. C++ is a multi-paradigm language. At beginning, it was procedure oriented. Then it's object oriented. During the past few years, functional oriented programming in C++ and even aspect oriented programming in C++ become hot topics and real possibility. Now why don't we give C++ a logic programming flavor? 4. UBL allows the programmer to switch back and forth among the multi-paradigm seamlessly, therefore make it easier to combine the right features of each paradigm to solve a given problem. Better yet, you do not need to lean a new language (Prolog). =========== Is UBL feasible?=================== The short answer is yes. I already have the prototype up and running in VC++ 7.1. The 8-queen problem takes less than 28 seconds on my Athlon 2200+ to find all answers. The prototype does have its fair share of shortcomings: 1. template based metaprogramming in general, and the prototype of UBL in particular, takes too long to compile any non-trivial code. Or may not be able to compile at all. 2. syntax wise UBL predicates are not as straight-forward or visually appealing as the equivalent predicates in Prolog. Here is a predicate in UBL: BOOST_UBL_PREDICATE_2_( is_grandfather_of, Person, Person ) { BOOST_UBL_VARIABLES_3 ( Person, X , Person, Y , Person, Z ); typedef clause< LHS<X, Y> , is_father_of< X, Z > , is_father_of< Z, Y > > type; }; Here is the equivalent predicates in Prolog: is_grandfather_of(X, Y) :- is_father_of(X, Z), is_father_of( Z, Y). 3. In my plan, the Lambda library will provide the "fast-lane" between UBL and your C++ instances, member functions and member variables. Of course, that is not done yet.

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Intel compiler
by Andreas Fabri 14 Sep '04

14 Sep '04

Do I have to do something particular for the Intel 8 compiler for Windows. I get error messages like: boost/type_traits/is_integral.hpp(38): error: class "boost::is_integral<unsigned short>" has already been defined BOOST_TT_AUX_BOOL_TRAIT_CV_SPEC1(is_integral,wchar_t,true) ^ thanks in advance, andreas

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Re: broken links and web site feedback...
by Aleksey Gurtovoy 14 Sep '04

14 Sep '04

William McDonald writes: > While trying to send the following message to boost(a)yahoogroups.com, > it bounced back. It's been a while since we switched to Mailman -- http://lists.boost.org/mailman/listinfo.cgi/boost. Does it still say 'boost(a)yahoogroups.com' somewhere on the website (besides http://www.boost.org/more/faq.htm -- just fixed this one)? > I'm not sure who handles broken links (i.e. who your web master is), > but this link only redirects if it doesn't have the 'index.htm' after > it. It is off the main library page > (http://www.boost.org/libs/smart_ptr/index.htm) Hmm, a search of "smart_ptr/index.htm" through all the docs/HTML pages didn't turn up anything. Are you sure the link came from the Boost website? > Broken link: http://www.boost.org/libs/smart_ptr/index.htm This one indeed doesn't work (should be "index.html"), but then it doesn't seem to be present anywhere on the website. > I recommend putting the web master's feedback link on the bottom of > every page. We don't have a single webmaster, but some address that doesn't require one to join a mailing list in order to report a typo or broken link indeed would be nice. Folks, do we have one already? > TIA, Thanks for your comments! -- Aleksey Gurtovoy MetaCommunications Engineering

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RE: [boost] Formal review of "Output Formatters" library begins today
by Reece Dunn 14 Sep '04

14 Sep '04

Paul A Bristow wrote: >* There is a terribly central spelling mistake which nobody seems to noted >so far: > > A _delimiter_ does de-limit things and has nothing to do with deli_s or >meter_s! > A global search in replace in code and docs is vital. <blush> >* I strongly dislike abbreviations and concatenations. It is MUCH easier to >read/understand and consistent with STL styling to use full words and _s, >if >a bit longer to type. naryfmt really must qualify for some prize. >nary_format or n_ary_format. > "Boost prefers clarity to curtness". I have been giving this some thought. What I am looking at at the moment is something like: std::pair < std::pair< int, std::vector< char > >, std::list< boost::math::quaternion< float > > > mct; namespace io = boost::io; namespace fmt = boost::io::format; std::cout << io::object( mct, fmt::pair ( fmt::pair( fmt::basic(), fmt::container()), fmt::container( fmt::nary()) ) ); With io::delimiter holding one of the delimiter values. io::wrapped_delimiter will replace io::openclose_formatter in holding open/close delimiter pairs and io::sequence_delimiter replaces io::formatter. >| 3. What is your evaluation of the documentation? OK - > > Though I am not a fan of background coloured boxes for code - I think >the >font change is enough. > > One thing I would REALLY REALLY like is a Boost 'Standard' way of >colouring and indenting code similar to Visual Studio IDE - though I don't >feel their colour scheme is quite as good mine! What do you think about the new Boost.quickdoc? The docs for quickbook are available at http://tinyurl.com/64el7, and the source is at http://tinyurl.com/4tdjj. Thanks to Eric and Joel for this great tool. >| 8. Do you think the library should be accepted as a Boost library? Yes >- >but with some name changes. See above. >And I would like to see active work by all authors to ensure that this >interacts with the filtering, range, more_io libraries before the first >actual full release (in 1.33?) so that the documentation cross-references >too, including examples of combinations of these techniques. I am willing to co-operate. >I can understand that authors are unwilling/unable to work together until >they are sure which other libraries can be assumed a part of Boost, and I >think we must accept (and flag up) that there will probably be changes, >perhaps major, while interworking is perfected. The three recent IO >contributions, with serialisation, are prime candidates for mutual >refinement. Sure. Regards, Reece _________________________________________________________________ Want to block unwanted pop-ups? Download the free MSN Toolbar now! http://toolbar.msn.co.uk/

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RE: [boost] 2. It is unavoidable to use threads
by Ben Hutchings 14 Sep '04

14 Sep '04

Carlo Wood <carlo(a)alinoe.com> wrote: <snip> > No, I am confused. You do as if it trivial. But where is the answer > to my question? How can I implement an interface that allows one to > wait for events on 100 sockets, a timer, a few named pipes, a fifo > and some large diskfile I/O at the same time? > Is your answer WaitForMultipleObjects ? Then 1) what about the limit > of 64? That limit may well be a problem. (As may the limit on the size of an FD_SET on POSIX systems with nothing better than select().) > And 2) How can I use that to wait for events on SOCKET's? The only > thing I can find for that is WSAWaitForMultipleEvents. > But obviously you can call WSAWaitForMultipleEvents *and* ^ not, presumably > WaitForMultipleObjects at the same time (without using threads). The WSAEVENT type alias and associated functions appear to have been defined as an attempt to allow for implementation on other operating systems; in reality a WSAEVENT is a HANDLE to a Win32 event and you can use it with WaitForMultipleObjects (this is documented in the Platform SDK).

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Legacy for compose?
by Daryle Walker 14 Sep '04

14 Sep '04

Looking at the main index.html file in CVS, it looks like the old Compose library will be going away. However at least one book, _The C++ Standard Library: A Tutorial and Reference_ by Nicolai M. Josuttis in 1999, assumes that Compose will still be there (and improved over what's in the book). Shouldn't our library list page permanently keep a note over what happened to the Compose library (and what should replace it)? -- Daryle Walker Mac, Internet, and Video Game Junkie darylew AT hotmail DOT com

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