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[dateTime] construting a date with time
by Sean Farrow 27 Feb '11

27 Feb '11

Hi: I'm currently doing some work with the boost date time library. Can the boost date class be constructed with a time, or do I need a separate time variable as well? If so, should I use a local time, or posix time, given that the time has already been converted from utc to the users timezone. Any help appreciated. Regards Sean.

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[Review] Phoenix V3: mini-review starts February 19th
by Hartmut Kaiser 27 Feb '11

27 Feb '11

Hi List, Phoenix V3 is nearing its completion. With the port to Boost.Proto we tried to address the outstanding issues of the review and would like to announce that the mini-review will start on February 19th. Feel free to preview the code at: https://svn.boost.org/svn/boost/sandbox/SOC/2010/phoenix3/ and the documentation at: http://svn.boost.org/svn/boost/sandbox/SOC/2010/phoenix3/libs/phoenix/doc/ht ml/index.html We are currently occupied with code cleanups and finishing of the documentation. The code itself is in a stable condition, feel free to make yourself comfortable with this new library. Regards Hartmut Phoenix V3 Review Manager --------------- http://boost-spirit.com

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[Filesystem] V3 interface inconsistency
by Peter Klotz 27 Feb '11

27 Feb '11

Hello I came across the following interface inconsistency in Boost.Filesystem V3 (Boost 1.46.0) in boost::filesystem::path Windows: const std::string string() const std::wstring& wstring() Linux: const std::string& string() const std::wstring wstring() We converted V2 code looking like this (necessary since filename() in V3 returns a path instead of a string): const std::string& filename=path.filename(); The converted V3 code: const std::string& filename=path.filename().string(); Obviously this code crashes in Linux since filename() returns a temporary object and string() returns a reference to one of its members. However this code works in Windows due to the different return types. My question: Wouldn't it make sense for all methods to return a value instead of a reference? It would ease the transition from V2 to V3 and avoid subtle programming errors. Regards, Peter.

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[Serialization] Testing if a provided file is actually a serialized archive
by Cedric Laczny 26 Feb '11

26 Feb '11

Hi, I would like to know if there exists a way to check for a given file if it is actually a serialized archive or a pure txt-file, at best without the need to read in that file completely. At the moment, I use boost::serialization to store self-defined class-instances in txt-files, so using something like the system's "file"-command would not bring me far. Now I would like my program to distinguish if the provided input-argument is a text-file that needs to be parsed or if it can simply restore this previous instance. Of course, using a separate option indicating if an archive was passed would work, but IMHO is not very beautiful. Best, Cedric

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XInt formal review forthcoming
by Vladimir Prus 25 Feb '11

25 Feb '11

Boosters, the review of Boost.XInt library, by Chad Nelson, is scheduled to start on Wednesday, March 2, and will run through Friday, March 11. I will be serving as review manager. Over the years, arbitrary precision arithmetics has been a hot topic on Boost mailing lists, but now we have a concrete proposal that may become an official Boost library. So, block the time on your calendar, and get ready. Thanks, -- Vladimir Prus Mentor Graphics +7 (812) 677-68-40

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obtaining the current timezone
by Sean Farrow 25 Feb '11

25 Feb '11

Hi: Is there a way using boost.datetime to obtain the current time zone. If not given the platform dependent nature of this what is the best way to write this so as to allow potential future integration in to the date time library. Regards Sean.

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[asio] using io completion ports
by Sean Farrow 25 Feb '11

25 Feb '11

Hi: Are there any examples in boost.asio that useio completion ports, and automatically obtain the queued input from them asynchronously? Cheers Sean.

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Bug in boost::phoenix ?
by Nicolas Savoire 25 Feb '11

25 Feb '11

I am using boost::phoenix lambda functions and I am observing some weird behaviours when compiling with optimizations (-O3). The first issue is that compiling the following piece of code Compiling: const float x = 1.0f; const float y = 1.0f; std::cout << (arg1+arg2)(x,y); with g++ -Wall gives the warning: boost_1_46_0/boost/spirit/home/phoenix/operator/arithmetic.hpp:74:5: warning: returning reference to temporary And I suspect a bug in the project I am working on is a consequence of this. It is as if a boost::for_each( rng, lambda_fun ) was optimized out. I have opened a ticket on this issue: https://svn.boost.org/trac/boost/ticket/5190 I suspect the issue comes from the type deduction inside phoenix. I first discovered the issue with boost 1.45.0, but it still here in 1.46.0. The other issue I am facing is similar. Consider the following code: namespace bp = boost::phoenix; using boost::phoenix::arg_names::arg1; int i=0; int a[] = {0}; template<class UnaryFunction> inline void foo( UnaryFunction fun ) { fun(i); } int main() { foo( bp::ref(a)[arg1]++ ); std::cout << a[0] << " "; (bp::ref(a)[arg1]++)(i); std::cout << a[0] << "\n"; } Compiled without optimizations, it corectly prints: 1 2 Whereas compiled with g++-4.5.1 -O3 with boost 1.45.0, it prints: 0 1, as if the first lambda invocation was removed. The issue disappears if I use g++-4.4 or boost 1.46.0. I tracked the changes between boost 1.45.0 and 1.46.0, and it seems related to https://svn.boost.org/trac/boost/changeset/66411 applying the part of the changeset concerning: fusion/support/detail/is_mpl_sequence.hpp fusion/support/is_sequence.hpp fusion/support/sequence_base.hpp to boost 1.45.0 fixes the issue, but I can't see how this is related to the bug I observed. Is it a compiler bug, a phoenix bug or a mistake in my code ? Thanks, nicolas

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Android NDK bjam toolset
by a b 25 Feb '11

25 Feb '11

Hello to everyone, I am interested if there is Android NDK support as a toolset in bjam, to build android binaries And if there is, some documentation would be also usefull. Thanks

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[config] platform macro
by Sean Farrow 25 Feb '11

25 Feb '11

Hi: What is the platform macro if boost is built on a win64 machine? I'm currently using this to detect the platform and selectively include files/file content and need to build on a win64 box. Any help appreciated. Cheers Sean.

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