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[outcome] Andrzej's review
by Andrzej Krzemienski 27 Jan '18

27 Jan '18

Hi Everyone, This is my review of Boost.Outcome v2. The library should be *accepted* subject to conditions that I list down below. What is your evaluation of the design? Clean and logically divided. What is your evaluation of the implementation? > Some bugs aside, it is clean and well structured. I was able to read it and understand how things work. I will be filing bugs in GitHub. What is your evaluation of the documentation? > Good. You can get the idea what the library is doing and how you can use it. But I should mention that I wrote some pieces thereof, so my opinion is likely biased. The docs need some modifications before they can get into Boost. I mean macro names, and the technology required to build it. What is your evaluation of the potential usefulness of the library? > I find the library very useful in certain domains. I myself have found two applications in my job project, and they are not really related to light-speed efficiency: 1. We have a task scheduling framework built atop ASIO, and signalling failures through exceptions makes the code really difficult to read because try-catch blocks need to work as control statements. Also, we cannot pass them by exception_ptr as sometimes we need to classify the kind of failure to determine if we want to deal with it in the framework, or if we want to forward them to the user. 2. I have a validation routine that validates (and parses) the input data written using some syntax. I wan the syntax-errors in input files to be forwarded as failed `result`s (no exceptional about these), but other errors like memory shortage during the file parsing to be signaled via exceptions (and I will probably kill the module in response). Why accepting this library when we have `expected` being standardized? I do not really mind having two in Boost. First, it is ready, being proposed, and applied in a number of non-trivial code-bases. Niall claims that his trade-offs are better tailored to predictable-latency applications. I do not have enough knowledge to asses it. They look convincing. The only way to test it is to give this library the Boost blessing and have the user test it. I am bought by the TRY operations, and the upgrade to `outcome` looks really convincing. Did you try to use the library? With what compiler? Did you have any > problems? > Yes. A lot of compilers. For instance GCC 6.4.0, also different GCC and Clang versions in WandBox. No problems encountered. How much effort did you put into your evaluation? A glance? A quick > reading? In-depth study? > I have read most of the final implementation. I have read many versions of the documentation. I have spent a lot of time (prior to the review) asking Niall lots of questions about the details. I have also built lots of small examples to test the library and some corner cases. Are you knowledgeable about the problem domain? > I do report failures (by different means) in my programs. I have given it quite some thought. I am well familiar with implementation and formal specification of `boost::optional` and `std::optional` which had to address some similar implementation problems. Do you think the library should be accepted as a Boost library? > Yes, conditionally. Here are three conditions: 1. Documentation is adjusted to use boost-standard names of macros and namespaces. Also, it is not clear if Boost release process is capable of handling the technology that Niall has chosen. If not, the contents of documentation should be migrated to another format, manageable by Boost release process. 2. Because there has been some confusion around the meaning of storing default-constructed `std::error_code` (is it an error or lack thereof?) and `std::exception_ptr` (e.g., see this issue: https://github.com/ned14/outcome/issues/115) I request that you state in the docs, before the API Reference how library treats default-constructed values of `EC` and `EP`. For instance, you can say "default-constructed error_code is considered an error, and treated as such by the library", or "the library sometimes may make use of the fact that a default-constructed EC/EP is not an error, so make sure not to pass us such values": I am fine with any answer, but I need you to spell it out, so that I know what to expect. 3. Similarly, I request that you put in the docs what is the "value" of an object of type `outcome<>` or `result<>` in the sense in which John Lakos talks about "salient attributes". I know that T, EC, and EP constitute the value. But in the middle of the tutorial we learn that apart from these you also store "spare_storage" -- is it also included in copying and comparisons? API reference on `operator==` only says "compares if two objects are equal", but it is not that clear what it means. Also, what does it mean that result is equal to optional. Define it somewhere and paste links to it. Finally, I wan to thank Niall for his now many-year effort to deliver this really cool library to the community. Regards, &rzej;

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Re: [boost] [review] Outcome: internal compiler error
by Vinnie Falco 27 Jan '18

27 Jan '18

On Thu, Jan 18, 2018 at 2:07 PM, charleyb123 . via Boost <boost(a)lists.boost.org> wrote: > GitHub: > *- https://github.com/ned14/boost-outcome > > Please post your comments and review to the boost mailing list > (preferably), or privately to the Review Manager (to me ;-). Here are some > questions you might want to answer in your review: I have put together the following sample program to test integration of Outcome into Boost.Beast: #include <boost/outcome.hpp> int main(int argc, char** argv) { } The result of compilation for this translation unit is shown here: 1>c:\users\vinnie\src\boost\boost\outcome\detail\value_storage.hpp(141): 1>fatal error C1001: An internal error has occurred in the compiler. 1>(compiler file 'msc1.cpp', line 1507) Compiler used: MSVC Part of: Microsoft Visual Studio Community 2017 Version 15.5.1 Upon investigation, I discovered a newer version of the compiler and IDE. Updating to "Version 15.5.5" produced the following results when compiling the same translation unit: 1>c:\users\vinnie\src\boost\boost\outcome\detail\value_storage.hpp(141): 1>fatal error C1001: An internal error has occurred in the compiler. 1>(compiler file 'msc1.cpp', line 1507) Is this a supported configuration? Thanks

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[review] outcome
by Vinícius dos Santos Oliveira 27 Jan '18

27 Jan '18

That is my review of Boost.Outcome. What is your evaluation of the design? Niall did an excellent job weighting trade-offs and coming up with such an pleasant and convenient interface that not only is convenient, but it has customization points in the appropriate layers to fit not-close-to-trivial use cases. I've read the changes between v1 and v2 and I agree with the rejection reasons of previous version (the v1's null state specially made little sense at all). Version 2 is a very realistic and solid project. It might seem teasing to just port abstractions from functional languages to C++ (e.g. Expected), but C++ is its own beast and we cannot just ignore some features that we have been dragging all along like exceptions if we expect to have any realistic usage in the real world. Niall's intuition on how to weigh trade-offs was outstanding and just proves his C++ familiarity and expertise. In special, default actions/behaviours could only be defined by intuition of some experienced programmer and not "mathematically". What is your evaluation of the implementation? I did not check the implementation. What is your evaluation of the documentation? Very well written. The tutorials are excellent-quality. The use cases and examples were chosen in such a way that it was intuitive to understand why/when Boost.Outcome and not Expected. I noted a few small problems, but they were reported already. The comments on the example codes were seemingly foreseeing ahead enough about "pumping doubts" so that my mind would calm down and actually pay attention to the documentation instead doing mind exercises trying to guess the non-point of the example. I wish I had this skill. What is your evaluation of the potential usefulness of the library? Very useful. Error handling is a core constant in any programming activity. Introduction of Boost.Outcome could potentially remove duplication of throwing and non-throwing APIs. I personally prefer Expected with its monadic operations, but it is unrealistic to ignore exceptions in many code bases and I'd certainly go for Boost.Outcome in these cases. Did you try to use the library? With what compiler? Did you have any problems? Yes. The one-header version of the library made testing incredibly easy. No problems. Clang 5.0.1. How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? A few hours over a span of a few days. I've tried to examine documentation carefully and end up sending a pull request and a few comments to ask for further changes. I've read all threads that came up during review. I also tested the library when in doubt. Are you knowledgeable about the problem domain? I worked for more than one year under contract using the Rust programming language and Boost.Outcome is pretty much the error system we have in Rust (with some C++-ification and an experienced C++ unique programmer "intuition" to also cover exceptions... and w/o monad ops, of course). Do you think the library should be accepted as a Boost library? Yes. -- Vinícius dos Santos Oliveira https://vinipsmaker.github.io/

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[config] Positive feature macros, r2
by Peter Dimov 26 Jan '18

26 Jan '18

I'd like to revisit the topic of Boost.Config feature macros, specifically that in my opinion, positive feature macros (BOOST_CXX17_FEATURE) make more sense than negative macros (BOOST_NO_CXX17_FEATURE) in the current environment. Negative macros made sense in the past when they signified bugs and deficiencies in the compiler as measured against a static standard. Nowadays, the standard, such as it is, is in constant motion and macros indicate merely a current state of development for both the compiler and the standard. The arguments for positive macros are the same as last time: - adding a new negative macro requires changes to all legacy compilers that do not and will never implement the feature; a positive macro only requires changes to active compilers. - positive macros are a better match for the standard feature macros, which are positive. When we see a standard feature macro being set, we typically would set ours as well. This means that the amount of changes required to add a new macro is further reduced; we only need to touch compiler-specific config files if the compiler either does not implement feature macros, or sets them incorrectly (in our considered opinion.) TL;DR we should switch to positive feature macros in Boost.Config, and delaying this switch just accumulates more unnecessary code in Boost.Config.

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[gsoc18][ublas] Proposal to add advanced matrix operations
by SHIKHAR SRIVASTAVA 26 Jan '18

26 Jan '18

Hi everyone, I am a 4th year undergraduate student pursuing a degree in Computer Science and Engineering. I have strong programming experience in C++ through internships, self projects and programming events. I wish to be a part of gsoc18 under boost and am particularly interested in the linear algebra library Boost.ublas. The ublas library can be made more useful for Machine Learning applications like recommendation systems, clustering and classification, pattern recognition by adding some operations required in those. I propose to add advanced matrix operations to ublas including - 1. Triangular Factorisation (LU and Cholesky) 2. Orthogonal Factorisation (QR and QL) 3. Operations to find Singular Value lists 4. Eigenvalue algorithms 5. Singular Value Decomposition (SVD) 6. Jordan Decomposition 7. Schur Decomposition 8. Hessenberg Decomposition This is a very brief description of what I would like to propose. Any suggestions that help in refining the requirements before making a draft proposal would be great. Regards Shikhar Srivastava Github: https://github.com/shikharsrivastava

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[outcome] success-or-failure objects
by Vinícius dos Santos Oliveira 26 Jan '18

26 Jan '18

I'm liking what I saw so far. Just a small comment on the documentation. I'm curious what the following sentence does even mean? Is it supposed to confuse the user or something? It's a sign of bad taste really. >Outcome’s default is to not provide value-or-error objects. It provides success-or-failure objects. What does that even mean? value-or-error... well, if it is non-error, I assume it is success. Both sentences mean just the same. As do their API (encapsulate either A or B). The rest of the paragraph is okay. If you just remove this comment, confusion will go away. No other changes need to be done in this paragraph. Just remove this misleading means-nothing comment. -- Vinícius dos Santos Oliveira https://vinipsmaker.github.io/

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[Root Pointer] Deterministic C++ memory manager (update)
by Phil Bouchard 26 Jan '18

26 Jan '18

Greetings, I wanted to give an update to the community regarding the memory manager I wrote called: Root Pointer. I now have a working template to solve all memory leaks in C++ and C but both requires some meta data generator. The code can be found here; it is working but not polished: https://github.com/philippeb8/root_ptr In this code we can find: - node_ptr: main class of the smart pointer / memory manager. - root_ptr: generic derived class that includes an "iterator" and a pointer to the name of the instance (for debugging purposes). Also I commented some code that logs the exact location of the memory leak. Furthermore I would like to bring some observations that I found in the C and the C++ language: - Pointers and iterators are not the same; i.e. pointers should point to allocated blocks only and shouldn't have arithmetic operators while iterators shouldn't be used to deallocate anything. - C pointers can only point to dynamic arrays (size known at run-time). - C++ pointers can point to both inherited objects and static arrays (size known at compile-time). This creates a problem (see attached: array_inherited_pointer.cpp). - std::array<T> should have constructors with T objects that have no default constructor. Lastly, before I submit anything, I will have to propose a way to apply a template function to all non-static member variables of a class. This will require implicit meta data generation. This idea is not new as other libraries such as Qt is based on meta data and they certainly could make us of this. For the moment I have a parser that does the job correctly by specializing a boost::proxy() template function but eventually this will have to be integrated into the standards. Hopefully this is an important milestone! Regards, Phil Bouchard www.fornux.com

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clang-format file
by Damian Vicino 25 Jan '18

25 Jan '18

Hi, I was wondering if someone has a .clang-format file that works fine to check boost code. I looked into the github repositories, but I couldn't find any. Best regards, Damian

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[outcome] Some documentation suggestions
by Vinícius dos Santos Oliveira 24 Jan '18

24 Jan '18

Maybe I could send some PRs later (I've already sent one a few moments ago). But, for now, I'll have to postpone. Notes: - You put too much focus in "open (error) type hierarchies" (e.g. `error_code`). Not a problem. Also, do not change anything just because this comment. Really, it is not a problem. - The beginning of the documentation gave me the impression that I could only use EC types that were convertible to `std::error_code`[1], “it need in fact to merely satisfy trait::has_error_code_v<EC>”. Later pages corrected my understanding. - “only works when the EC type is the same in the try expression as the calling function”[2] is misleading. `OUTCOME_TRYV(outcome::result<int, err>{err::success})` works inside a function returning `outcome::result<void>` given `err` is convertible to `std::error_code`. [1] https://ned14.github.io/outcome/tutorial/payload/ [2] https://ned14.github.io/outcome/tutorial/default-actions/error-codes/ -- Vinícius dos Santos Oliveira https://vinipsmaker.github.io/

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[outcome] comments on Regular ops
by Andrzej Krzemienski 24 Jan '18

24 Jan '18

Hi Everyone, This is not my final review (yet), but I wanted to raise some issues with Regular ops: comparisons and swap. 1. Comparisons. Equality comparison for `result` makes a strange choice for `T`s without comparisons: two such `result<T>`s just compare unequal. This is somewhat contradictory to semantics of Regular types. For value-semantic types we expect that a copy of the original object `x` compares equal to `x`: ``` int i = 1; int j = i; assert (i == j); ``` For some types, copy-construction makes a copy with the same value, but there is no way to define operator==. In this case, in order not to confuse anyone operator== is simply not provided: ``` using transformation = std::function<int(int)>; transformation f = [](int i) { return i; }; transformation g = f; // assert (f == g); <-- does not compile ``` And now, when we wrap it into `result`, we get: ``` // continuing previous example: out::result<transformation> of = f, og = g; f == g; // <-- compiles fine, returns false. ``` Now you are just telling lies. Two objects have the same value, yet they compare unequal! Here is a live example: https://wandbox.org/permlink/I hqgXDfHW6WqAXHW My recommendation would be not to provide comparison operators if either `T` or `EC` does not provide them. 2. Swap For non-trivially-copyable types, it looks like (similarly to std::variant) `result` cannot provide the strong exception safety guarantee. You may need to both move-construct `T` and `EC` and both can fail. ``` void swap(result &o) noexcept(detail::is_nothrow_swappable<value_type>::value // &&detail::is_nothrow_ swappable<error_type>::value) { using std::swap; #ifndef BOOST_NO_EXCEPTIONS this->_state.swap(o._state); try { swap(this->_error, o._error); } catch(...) { swap(this->_state, o._state); throw; } #else swap(this->_state, o._state); swap(this->_error, o._error); #endif } ``` The trick with catch-reswap-rethrow assumes that `T` is more likely to throw while swapping/moving than `EC`, but it might be quite the opposite. Also, it is possible that while reswapping, another exception will be thrown. In general, you cannot guarantee the roll-back, so maybe it would be cleaner for everyone if you just declared that upon throw from swap, one cannot rely on the state of `result`: it should be reset or destroyed. Another problem is that in the noexcept() clause you are mentioning is_nothrow_swappable<value_type> and is_nothrow_swappable<error_type>, but in the implementation you might be using move constructors rather than swaps. This means that for types that do not throw in swap but throw in move constructor (like std::list), a throw from move constructor will cause a call to `std::terminate`. See live example here: https://wandbox.org/permlink/8jIyb0fx7U72cZSt The noexcept clause should be extended to include move-constructors. This is the case for `std::optional`. Regards, &rzej;

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yomm2 - open methods
by Jean-Louis Leroy 24 Jan '18

24 Jan '18

Hi, in 2013 I posted a proposal for an "open multi-methods" library, see here: https://lists.boost.org/Archives/boost/2013/07/205383.php Due to insufficient interest, I did not go forward with a formal submission, and I published my work on github, under the name yomm11. I have now completely rewritten the library. The new version - yomm2 - is available here: https://github.com/jll63/yomm2 This iteration is much better because it does not require any modifications to classes involved in method dispatch, yet the speed of a method call with one virtual argument is within 15% of the equivalent virtual function call. Over the years I realized that the value of such a library resides more in the 'open' than in the 'multi' aspect. Open methods are virtual functions that live outside classes, like free functions. They solve several problems, notably the Expression Problem (http://wiki.c2.com/?ExpressionProblem) and Cross-Cutting Concerns (http://wiki.c2.com/?CrossCuttingConcern) They provide an elegant replacement for the Visitor pattern. yomm2 also implement multiple dispatch, which can come (occasionally) handy. Well I am just touching base to see if things have evolved and if there might now be an interest in seeing this in Boost. Jean-Louis Leroy

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Contributing in the algorithm library
by Surayans Tiwari 24 Jan '18

24 Jan '18

Hello Boost Community! My name is Surayans Tiwari currently pursuing Bachelors of Engineering at BITS Pilani, India . I am an algorithms enthusiast and c++ programmer with 3 years of experience coding in the language. I want to get a head start on how to add new modules in algorithm library of boost. Please can someone help me with this. Thank you. ‌

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[outcome] Whether to default EC = error_code for result?
by Niall Douglas 23 Jan '18

23 Jan '18

Just wondering what the reviewers' opinion is on the choice by Outcome to default `result<T, EC = std::error_code>`? That made sense back when Boost.System's error_code aliased `std::error_code` when being compiled under C++ 11 or better (i.e. always in the case of Outcome). But now that Boost.System's error code looks to be becoming a superset of `std::error_code`, I am now wondering whether to no longer default it at all to anything. Arguments in favour of this: 1. Expected no longer defaults E to anything, thus avoiding including <system_error> which drags in <string> and imposing compile time costs on those who don't use <system_error>. I did some more benchmarking, on a recent GCC on a 4Ghz CPU it's about 0.6 secs per compiland being added on Linux, and more like a second on Windows with MSVC. 2. As is pretty clear from the tutorial, we expect all non-trivial uses of Outcome to typedef `result` into the local namespace anyway. So defaulting `EC` only really benefits trivial use cases. 3. I think it now inevitable I need to go implement a much lighter weight <system_error2> without the problems with <system_error> (e.g. header only use problems, heavy includes, underspecified semantics, hardcoded use of `int`, memory allocation and so on). I'll send it to SG14 for them to get it into the standard if they like it (they will, it'll tick all their boxes, WG21 may be more challenging). Arguments against this: 1. Use of `std::error_code` ought to be encouraged rather than UDTs such that Outcome using code is not anti-social to other code. Defaulting the type sends a clear message on this. 2. Removing the defaulted `EC` on `result` is asymmetrical to defaulting `EC` and `EP` on `outcome`. I personally don't mind it, different typical use cases means different defaults, but others may find the asymmetry upsetting. 3. The relevant policies need to include `<system_error>`, otherwise they don't compile. So the include of `result.hpp` would need to be split into a `result.hpp` and a `error_code_support.hpp` with the latter containing the `<system_error>` stuff. Thoughts? Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

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23 Jan '18

While refactoring the test Jamfile for Boost.System, I wrote this rule: rule system-run- ( sources + ) { local result ; result += [ run $(sources) : : : <link>static : $(sources[1]:B)_static ] ; result += [ run $(sources) : : : <link>shared : $(sources[1]:B)_shared ] ; result += [ run $(sources) : : : -<library>/boost/system//boost_system <define>BOOST_ERROR_CODE_HEADER_ONLY : $(sources[1]:B)_header ] ; return $(result) ; } to avoid repeating each test three times. The inconsistency is somewhat annoying. We could normalize the third line by introducing a third link type, <link>header, in response to which the library can switch to header-only mode. This is more or less the same suggestion as Niall's _hl targets from the CMake discussion, but it fits Boost.Build better, because the <link> property is automatically propagated to dependencies. Furthermore, after thinking about it a bit, I think that we might even have room for a fourth link type, <link>source, in response to which the library target would pass an appropriate <source> usage-requirement upwards. (<source>error_code.cpp in Boost.System's case.) <link>source is kind of best of both worlds, as it doesn't reparse the source code each time the library is used, and at the same time is not prone to the ODR violations introduced by inadvertently compiling the library and the executable with different, ABI-incompatible options. Comments?

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[git][releases] removing beta tags
by Raffi Enficiaud 22 Jan '18

22 Jan '18

Hi all, I would like to know if it is allowed to delete the git tags that are associated to beta releases (such as "boost-1.45.0-beta1"). Thanks, Raffi

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[trac] email notifications?
by Raffi Enficiaud 22 Jan '18

22 Jan '18

Hi, Is trac sending email notification on comments and changes regarding tickets? It used to do so, but I am not receiving anything. I am asking because I am waiting for ppl to comment on the tickets for some time. If people do not receive email notifications, I think I will wait for ever. Thanks, Raffi

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[trac] new versions of boost
by Raffi Enficiaud 22 Jan '18

22 Jan '18

Hi there, Would it be possible to add the next versions of boost to trac/milestones ? Thanks! Raffi

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[system] Would it be possible to trial a breaking change to Boost.System and see what happens?
by Niall Douglas 22 Jan '18

22 Jan '18

SG14 the low latency study has been looking into how to improve some design decisions in <system_error>. The relevant WG21 paper is https://wg21.link/P0824 and recent discussion can be found at https://groups.google.com/a/isocpp.org/forum/#!topic/sg14/j7tQybEjP5s. What we'd like to do is to test whether some very mildly breaking changes to <system_error> are so mild as to affect no users, and on that basis propose WG21 to make those mildly breaking changes to <system_error> in the next C++ standard. And to test this, we'd like to modify Boost.System with those mildly breaking changes, ship a release and see how many users complain. If it is zero, we have evidence for WG21 that this is not a consequential change. What we'd like to change is this: 1. Stop treating code zero as always meaning success irrespective of category. This remedies a defect where some custom error code domains cannot be represented by error_code due to using value 0 for an error. In actual code, I've never seen anyone ever use comparison to anything but a default constructed error code, so I think this will be safe. 2. Success becomes solely the default constructed error code, which is code zero and a new category of "null_category". This is internally represented by { 0, nullptr }, and thus makes the default constructor trivial which is highly desirable as it eliminates any compiler magic static fencing for the default constructor. Right now the default constructor uses system_category with value 0, and I suspect no code will notice this change either. 3, Make the default constructor constexpr, now possible. No code should notice a difference, except less runtime code will be generated. 4. error_code::message() returns a std::string_view instead of std::string if running C++ 17 or better. This lets us remove the <string> dependency, and thus stop dragging in half the STL with <system_error> which in turn makes <system_error> actually useful to the embedded systems crowd. The guess here is that std::string_view has such excellent interoperation with std::string that I think 99% of code will compile and work perfectly without anybody noticing a thing. I appreciate that this would undo Peter Dimov's excellent work at having Boost.System alias <system_error> under C++ 11 and later. I also appreciate that we are deliberately going to potentially break end user code. But my personal guess is that in practice, the breakage will not be noticed by 99% of code out there right now. It'll just compile against the improved Boost.System and everything will work as before. Boost was originally intended as an incubator for C++ standard changes. This ticks that box perfectly. Thoughts on feasibility? Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

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Travis CI Resources
by James E. King, III 22 Jan '18

22 Jan '18

Last summer we had a discussion about Travis CI Resource Usage for boostorg. Originally the discussion was about purchasing more resources; however the discussion quickly focused on finding the root cause of the backlog. The desire is to ensure that pull requests submitted to repositories are processed in a timely manner. This is not happening, and there is at least a 12 hour backlog on pull request builds for boostorg right now. Summarizing the discussion back then, it was proposed that the backlog was caused by folks working on feature branches directly in their boostorg repository, with the Travis CI setting enabled to "build branch updates". The proposed solution was to encourage everybody to fork their repository and set up their own Travis CI and Appveyor under their account, and work feature branches on your fork. If working alone, this is efficient for everyone as we all end up with faster builds because your account will not contend with boostorg for resources. So please, use your personal account to build up features if you can. Additionally, tuning your Travis CI build script to do a little bit less work will help. If you have a script that builds with gcc, gcc-5, gcc-6, gcc-7, clang, and cxxstd of 03,11,14,1z - for most libraries that are at the c++03 language level this is going to be significant overkill for use as a pull request gate. In the example above, there are 20 builds to do; double that if you build debug and release variants. If each build takes just 2 minutes that's still an 80 minute CI cycle. Please spend some time reviewing your practices around the use of the free CI resources we all share. Thanks, Jim

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[config] Supporting newer compilers: what does it take?
by Olaf van der Spek 22 Jan '18

22 Jan '18

Hi, What does it take to support new compilers, especially MSVC? 15.6 Preview 1 has been released now. Is some documentation or policy regarding test runners etc available? https://blogs.msdn.microsoft.com/vcblog/2017/12/19/c17-progress-in-vs-2017-… Gr, -- Olaf

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[gsoc18] RSS
by Greger 22 Jan '18

22 Jan '18

Got some code/idea for RSS. possibly an GSoC18 topic?anyone? br g

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[bjam] Can I disable a test based on an environment variable?
by James E. King, III 21 Jan '18

21 Jan '18

I'd like to disable some serialization tests if I am running a ubsan build on travis. Is there a way in the Jamfile I can make it conditional on an environment variable, or should I define something like BOOST_DATE_TIME_UBSAN and put "if !defined" in the appropriate tests?

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[gsoc2018] Dynamic Shortest Path Tree
by a.i＠acm.org 21 Jan '18

21 Jan '18

Hi, I am Donghyuk Kim, a Ph.D. Student at Korea Advanced Institute of Science and Technology. I tried to contribute something last year but was not able to start the project for some reason. So I am about to re-try again this year. What I would like to contribute is a specific algorithm, "Dynamic Shortest Path Tree" which is simply, a dynamic version of Dijkstra's algorithm. It is a tree-based data structure to maintain single-source to all destination shortest paths and known to outperform Dijkstra or A* where the insertion and deletion of vertex/edge frequently occur. The concept of "Dynamic Shortest Path Computation" was originally introduced in [Fully Dynamic Algorithms for Maintaining Shortest Paths Trees] by D. Frigioni, et al. (http://dl.acm.org/citation.cfm?id=338900) I have already implemented a working prototype for my research, but unit test, coding style unification, and much more c++ style modifications are required for the general purpose. I hope someone finds it interesting and be a mentor on this journey. Thanks in advance. Best Regards, Donghyuk Kim a.i(a)acm.org _____________________________________ Sent from http://boost.2283326.n4.nabble.com

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[gsoc18] SafeFloat proposal
by Damian Vicino 21 Jan '18

21 Jan '18

Hi, I added a proposal to get SafeFloat ready for review: https://github.com/boostorg/boost/wiki/Boost-Google-Summer-of-Code-2018#3-b… This was a project I started in gsoc2015 as student mentored by Robert Ramey. Please contact me if you are interested in further details. Best regards, Damian Vicino

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Google Summer of Code 2018
by David Bellot 20 Jan '18

20 Jan '18

Dear Boost community, once again this year, we will apply to be a mentoring organization for the Google Summer of Code 2018. Our organization has been quite succesful for the last decade and this year we hope to be selected again. As part of filling in our application for 2018, we must supply to Google a list of potential GSoC mentors and potential GSoC projects for summer 2018 in order to be approved as an organisation this year. Therefore a lengthy page of awesome project ideas at https://svn.boost.org/trac/boost/wiki/SoC2018 before *January 23rd* would be an enormous help to getting us approved again this year and bringing to Boost another Google funding (worth dozens of thousands of dollars on average). If you think yourself able to mentor a student doing some work on Boost this summer, *please* consider adding a description of the proposed work item and your name to the list. If you want to have a better chance receiving funding for your project ideas, it is better to find good students early and that is best done by getting project ideas floated *early*. If you want to know more about mentoring a Google Summer of Code funded student work before you nominate yourself, please feel free to ask on the main Boost developers mailing list boost(a)lists.boost.org or via gsoc-admin(a)boost.org. Thank you in advance for your time. Finally, I would like to thank Niall Douglas, our previous Boost admnistrator for GSoC, who did an awesome work during many years and helped the Boost community grow thanks to all the funding we received years after years from Google. Best regards, David

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