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[BGL] graphml support update
by Tiago de Paula Peixoto 23 Aug '06

23 Aug '06

Actually this message is just to check if the last update I sent was noticed... http://article.gmane.org/gmane.comp.lib.boost.devel/146836 I don't mean to hurry at all, but it's been over a week without comments, specially from Douglas Gregor who seemed interested in this, and since sometimes threading can cause messages to be unnoticed, I get a little paranoid. Sorry. ;-) -- Tiago de Paula Peixoto <tiago(a)forked.de>

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Re: [boost] [Monotone-devel] [Program Options] cannot use Boost.Program_Options with an i18nized program
by Julio M. Merino Vidal 23 Aug '06

23 Aug '06

On 8/23/06, Richard Levitte - VMS Whacker <richard(a)levitte.org> wrote: > In message <20060823114655.GA18897(a)frances.vorpus.org> on Wed, 23 Aug 2006 04:46:55 -0700, Nathaniel Smith <njs(a)pobox.com> said: > > njs> so let's move on to door two... which is to give the calling > njs> program enough information on whatever errors have occurred > njs> that it can do its own error reporting. > > While I understand the expedience argument, I'm dubious about > duplicating the error reporting of another package. It demands a > level of synchronisation between two independent entities and is prone > to mistakes or outright errors. The idea makes my skin crawl, to be > honest. Nevertheless, exceptions should always provide the caller a way to obtain the relevant information because the message they include may not always be appropriate (nor targetted to the end user). Also, other than printing the message, you might need to handle this information somehow in your code, so you need a way to access it. (I know there is a page in the Boost site (?) that deals with exactly this issue but I cannot find it now...) -- Julio M. Merino Vidal <jmmv84(a)gmail.com> The Julipedia - http://julipedia.blogspot.com/

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Re: [boost] Boost Units library preview
by Andy Little 23 Aug '06

23 Aug '06

"Andy Little" <andy(a)servocomm.freeserve.co.uk> wrote in message news:... > It could be in Quan, by more querying of the unit and disallowing the > calculation in this case. At one point Quan (in a previous incarnation) did do > this, but then maybe there are situations where adding or comparing torque and > energy is appropriate, so I opted for the freer semantics. If there is a proof > of some sort that they can never be compared or added then I will change the > current semantics, but I am not enough of an expert to say for sure. I should clarify that by a proof I mean a proof that no two dimensionally equivalent, but different, quantities can ever be added, rather than just torque and energy. It isnt possible to proceed on a case by case basis as there is an infinite number of scenarios. regards Andy Little

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[Program Options] cannot use Boost.Program_Options with an i18nized program
by Nathaniel Smith 23 Aug '06

23 Aug '06

We discovered this issue when we recently switched the program monotone[1] over to using program_options instead of popt -- one of our translators pointed out that he had started getting command line syntax errors reported in English, regardless of the setting of his locale. The problem lies in program_options/errors.hpp: http://boost.cvs.sourceforge.net/boost/boost/boost/program_options/errors.h… Most exceptions defined in this file construct their full error message as an opaque string, and do not provide the calling program equivalent information in any other form. For instance, the 'unknown_option' exception on line 45 simply does: : error(std::string("unknown option ").append(name)) and there is no way to extract 'name' from the exception object, except by parsing this string (ugh). If there is a 'syntax_error', then member variables are provided to access the pieces used to construct the error string, but one of these member variables is simply 'msg', again an opaque English string. I can think of two approaches to make this library usable in programs that are not monolingual English -- there may be others. The first is to design and write a portable, cross-platform method to deploy and access message catalogs, and then ship Boost with translations of all such strings into every language. While this might be a diverting way to spend a few years, it doesn't seem like an immediately practicable solution[2], so let's move on to door two... which is to give the calling program enough information on whatever errors have occurred that it can do its own error reporting. This does mean that the sorts of errors that could occur would become part of the public API (no more opaque "msg" strings), but ATM these errors are part of any program using this library's _U_I, and this API exposure is the inevitable cost to be paid if Boost isn't prepared to provide translations internally. So, would it be possible to make the interface exposed by errors.hpp considerably more fine-grained? -- Nathaniel (Reply-to-all appreciated.) [1] http://venge.net/monotone [2] Well, unless we just decided to declare gettext to be a Boost library, but I get the impression that the process is a bit more complicated than that :-). -- So let us espouse a less contested notion of truth and falsehood, even if it is philosophically debatable (if we listen to philosophers, we must debate everything, and there would be no end to the discussion). -- Serendipities, Umberto Eco

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[Boost-bugs] [ boost-Feature Requests-1545187 ] [jam] HardLink rule on NT platform
by SourceForge.net 23 Aug '06

23 Aug '06

Feature Requests item #1545187, was opened at 2006-08-23 03:16 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=357586&aid=1545187&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: None Group: None Status: Open Resolution: None Priority: 5 Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: [jam] HardLink rule on NT platform Initial Comment: I've installed boost and noticed that HardLink rule on NT copies file although NT has support for hardlinks (on NTFS, of course). To use this feature while installing boost i've created file hardlink.bat with following contents: fsutil hardlink create %2 %1 and put it into %WINDIR%\system32 also i've changed line 194 of tools\build\v1\allyourbase.jam file from LN ?= $(CP) ; to LN ?= hardlink ; these changes allowed me to save about 600 M of my harddisk space. Not a big deal, yes, but otherwise these 600M would exceed my disk space :-) I think my solution is not ideal, but it could be helpful for people. So maybe it will be included in boost distibution, when adapted. Thanks. mailto: forums (dog here) green dot nsk dot ru ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=357586&aid=1545187&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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[Boost-bugs] [ boost-Support Requests-1545133 ] Boost.Format doesn't work on MSVC with /vd2 compiler option
by SourceForge.net 23 Aug '06

23 Aug '06

Support Requests item #1545133, was opened at 2006-08-23 12:50 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=207586&aid=1545133&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: None Group: None Status: Open Resolution: None Priority: 5 Submitted By: SMART_n (smart_n) Assigned to: Nobody/Anonymous (nobody) Summary: Boost.Format doesn't work on MSVC with /vd2 compiler option Initial Comment: The problem is that Boost.Format doesn't work(raise exception) with /vd2 compiler option on Microsoft Visual Studio 2005. Is it possible to use Boost.Format with this compiler option? ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=207586&aid=1545133&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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Presentation of Boost.Process (SoC project)
by Julio M. Merino Vidal 23 Aug '06

23 Aug '06

Hello, During the past two-three months Jeff Garland (as mentor) and I have been working on the Boost Summer of Code project whose goal was to implement a library to spawn and manage child processes. A little introduction and a link to the source code can be found here: https://www.boost-consulting.com:8443/trac/soc/wiki/process But you'll probably want to go straight to the documentation which includes, among many other information, a couple of tutorials and multiple examples. I'm keeping an up-to-date snapshot at the following URL: http://www.NetBSD.org/~jmmv/process/ If it wasn't for the imminent SoC deadline (next Monday), I wouldn't present it just yet because there are still a couple of important issues that I would like to see resolved as soon as possible: First is the lack of a "design decisions" chapter in the documentation. This is not an extremely big issue because the Wiki page linked above already contains many discussions on the library's current design. In other words, that chapter will end up summarizing the information in there and adding few new things. Second, and very important, is the "need" to integrate the library with Boost.Asio to allow asynchronous management of communication streams and process termination. Unfortunately it does not support such asynchronous events yet, and integrating with Boost.Asio sounds like a reasonable approach to cover this area. Anyway, I wouldn't like this to discourage you from taking a look at the documentation and code. The library is already big enough to let you get a general idea on its focus and design. You can start criticising now! ;-) Sincerely, any constructive comments will be certainly appreciated. Thank you. PS: I'd be great if you could attempt to run the test suite on any platform not listed in the "Platforms and compilers" chapter. PSS: I hope to continue working on it after SoC is officially over. -- Julio M. Merino Vidal <jmmv84(a)gmail.com> The Julipedia - http://julipedia.blogspot.com/

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[facets] strict_num_put design problem
by Johan Råde 23 Aug '06

23 Aug '06

Robert Ramey has evicted my facets for non-finite numbers from the serialization namespace :-) They clearly don't belong there. So I've moved them to a new facets namespace. I have moved the code in the vault from the Serialization folder to a new Facets folder. And I have started a new thread. ------------------------------------------------------------------------- There is a serious problem with the design of the facets strict_num_put and strict_num_get. These facets are supposed to set the failbit of the stream when they encounter non-finite numbers. This may not be a good idea, because Facets derived from std::num_put and std::num_get should do formatting and parsing, not data validation. The designers of the standard library made the following assumptions: 1. Facets derived from std::num_put do formatting. 2. Facets derived from std::num_get do parsing. 3. Formatting always succeeds. 4. Parsing may fail. This led them to the following design decisions: 5. Facets derived from std::num_put do not have access to the stream state. 6. Facets derived from std::num_get do have access to the stream state. The facets strict_num_put and and strict_num_get violate assumptions 1 and 2. The facet strict_num_put does validation and formatting. The facet strict_num_get does parsing and validation. This makes it difficult to implement strict_num_put. What should it do when validation fails? It can not set the failbit of the stream. The only thing it can do, is to throw an exception. The stream will catch that exception and set the badbit! At least with VC++ 7.1. Why? The stream probably assumes that formatting facets do not throw exceptions, so it concludes that the exception was thrown by the stream buffer. When the stream buffer is corrupted, the stream sets the badbit. However, setting the badbit when data validation fails, is a bad idea. Suggested solution: Throw out the facets strict_num_put and strict_num_get. Comments? The documentation of the library has been updated to reflect this problem. --Johan Råde

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fixed-point math library?
by Michael Marcin 22 Aug '06

22 Aug '06

Does boost have a fixed-point math library? -- Michael Marcin Method Solutions, Programmer

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Yet another concept checker
by Chad Parry 22 Aug '06

22 Aug '06

I would like to know if many people in the community think the following library would be useful. I would like to define concepts using this syntax: template<typename left_type, typename right_type = left_type> struct less_than_comparable { static var<left_type const> left; static var<right_type const> right; static var<bool> b; typedef CONCEPTS_USE_PATTERN(b = (left < right)) constraints; }; In the code above the less_than_comparable<T, U> concept is defined. The var<> type is meant to resemble the Var<> in Stroustrup's concept proposals. The CONCEPTS_USE_PATTERN(EXP) macro expands to BOOST_TYPEOF(EXP). The b, left and right variables have lambda-like capabilities where you can apply any operation on them and they return a complex type that remembers what operations have been applied. Functions that want to enforce concepts would use this syntax: template<typename operand_type> bool my_less_than(operand_type left, operand_type right) { // Enforce the model. typedef less_than_comparable<operand_type> model; BOOST_STATIC_ASSERT(is_match<model>::value); constrained_proxy<1, model> constrained_left(constrain<1, model>(left)); constrained_proxy<2, model> constrained_right(constrain<2, model>(right)); // Use the constrained proxies just like regular types. return (constrained_left < constrained_right); } Obviously this syntax is more cumbersome than the current Boost Concept Check Library's. But it offers more power too: 1) The author doesn't have to hand-craft an archetype class! The model knows what operations should be allowed and the constrained_proxy<> class enforces that only those operations are taken. 2) It is possible to check whether a model is valid without causing a fatal error. That's what the is_match<model> metapredicate is for. This could be used to dispatch different optimized code depending on which concepts the type is known to model. Now, there are some things that can't be detected by library code (like the presence of a default constructor) so I would have to rely on authors to provide hints about those. I'm planning on just assuming that any requirements I can't detect are fulfilled, and then the compiler will complain if that's wrong. 3) The concepts can be built up from primitives using and_ and or_ and not_ operations, just like in Stroustrup's proposals. For example, the concept above could have included this statement instead: "typedef and_<CONCEPTS_USE_PATTERN(b = left < right), CONCEPTS_USE_PATTERN(b = right < left), copy_constructible<left> > constraints;" 4) This use pattern syntax more closely resembles the C++0x use pattern proposals than any other existing library. 5) The constrained_proxy class prevents certain errors where a pathological type behaves unexpectedly. I'm talking about functions like "evil_bool_proxy operator<(mytype, mytype)" where evil_bool_proxy defines its own && and || operators. In the expression, "(a < b) && (c < d)" the constrained_proxy enforces that the && operation gets applied to bool values, not to evil_bool_proxy values. 6) This mechanism allows you to express that a model has important semantic implications also. The library assumes that a model is valid if it is a structural match. But you can override that by saying, "template<typename value_type> declare_match<forward_iterator<istream_iterator<value_type> > > : false_ { };" 7) Traits classes could potentially be added to this library so that authors could express mappings such as that the constrained_proxy should call a free function "push_back(my_seq, elem)" instead of the normal "my_seq.push_back (elem)" for a given sequence type. So far I have gotten var<> and declare_match<> and is_match<> to compile. I've also finished and_<>, or_<> and not_<>. I'm working on constrained_proxy<>. -- chad

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