November 2008 - Boost-users

[format] How to trigger compile-time error for mismatched arguments
by Jeffrey Chang 11 Nov '08

11 Nov '08

Hi, I'm using boost::format library, and this may be obvious to those experienced users: is there any way to detect the mismatch of number of expected arguments in a boost::format object? Both of the following statements throw out runtime exceptions (which is correct): std::cout << boost::format ("%s %s") % "Hello"; std::cout << boost::format ("%s") % "Hello" % "world"; It'd be great if this type of parameter-mismatch error can be caught at compile-time, instead of run-time. We use boost::format library extensively for logging, and inevitably there're human errors like this mismatched number of arguments. IMHO, this kind of error should have been detected by compiler at build time, s.t. the developer won't be embarrassed by QA or customers at run-time. Actually, what's even worse is the following that doesn't generate error at all: std::cout << boost::format ("%s %s") % "Hello" % 12345; There's a type-mismatch ('char*' versus 'int') for the second argument, but there's neither compile-time nor run-time error. The output is "Hello 12345", which may be correct, but it may not be what the programmer intended to do. Any way of turning those typo into compile-time error? --- Jeffrey

2 1

Boost MPI + Serialization
by Raymond Wan 11 Nov '08

11 Nov '08

Hi all, I am using Boost MPI and would like to send user-defined objects between processes. As the Boost MPI tutorial / documentation suggests (http://www.boost.org/doc/libs/1_37_0/doc/html/mpi/tutorial.html) I should use serialization and in this document, they show an example class gps_position which is a friend with boost::serialization::access. So far, I understand what's going on, but I don't know what is the next step. The example in the documentation stops there and says that the example continues in the Serialization document. It also just mentions that one could store it in many forms, such as XML on disk, in addition to sending it to processes. If all I want to do is send it between processes, which one of the formats listed in boost/archive/*.hpp should I use? In the Serialization document, it continues by creating a boost::archive::text_oarchive object. But, if I am sending things like vectors of unsigned integers and strings, a binary format should be more compact? Or does this not matter and sticking with the Serialization example is fine? Thank you in advance! Ray

2 2

[signals2][review] The review period of the signals2 library is over
by Stjepan Rajko 10 Nov '08

10 Nov '08

Hello all, The review period of the signals2 library finishes today, November 10th. I would like to thank the author, Frank Mori Hess, for preparing the library for review and for diligently answering questions, and all those that have participated in the review for their thoughtful comments and reviews. A few more reviews will be coming late - if anyone that hasn't contacted me yet would like to submit a review in the following few days please let me know so I know to wait for your review. I will start working on summarizing the content of the reviews and comments submitted so far, and will post a report within a week. Kind regards, Stjepan

1 0

[boost.python] Hello world example of is not working with msvc
by Sandeep Gupta 10 Nov '08

10 Nov '08

Hi, I am reasonably sure that this is due to omission in the configuration file. I checkout from the trunk and all compilation went without problem. But the hello world example within the boost.python is failing with error: LINK : fatal error LNK1104: cannot open file 'boost_python-vc80-mt-gd-1_38.lib' call "f:\Program Files\Microsoft Visual Studio 8\VC\vcvarsall.bat" x86 >nul link /NOLOGO /INCREMENTAL:NO /DLL /DEBUG /subsystem:console /out:"bin\msvc-8.0\debug\hello_ext.pyd" /IMPLIB:"bin\msvc-8.0\debug\hello_ext.lib" /LIBPATH:"F:\CodeBase\Libs\Python-2.5.2\PCbuild8\win32release" @"bin\msvc-8.0\debug\hello_ext.pyd.rsp" .... .... >From what I can make that LIBPATH doesn't have path to boost_python-vc80-mt-gd-1_38.lib. The lib in question is build at its requisite place. Appreciate any help. Thanks sandeep

2 1

iphone port
by Gustavo Garcia Bernardo 10 Nov '08

10 Nov '08

Is it possible to build boost library to be used in the iphone? I'm a newcomer in this list, I apologize if this is a repeated or silly question. Thank you very much. G.

4 4

Turn off versioning in Serialization
by Brian Nantz 10 Nov '08

10 Nov '08

I am using serialization split member (save & load) and it works great. I am using a text archive, but I do not want the framework to put the "version header" in the string (e.g. 22 serialization::archive 4 1303 ). I want to simply serialize the string and handle the versioning myself in the load function. Is there a way to turn this off? If not, where can I find detailed documentation on implementing a custom archive or build in another type of serialization (other than binary and xml nvp)? I have looked through mailing lists and documentation but I don't see a detailed description of how to extend the design. Brian

2 1

Re: [Boost-users] [Database] question about database
by raindog＠macrohmasheen.com 10 Nov '08

10 Nov '08

A decent candidate could be SOCI. It is hosted on sourceforge and to my knowledge is being modified for eventual boost submission ------Original Message------ From: Mario Chacon Sender: boost-users-bounces(a)lists.boost.org To: boost-users(a)lists.boost.org ReplyTo: boost-users(a)lists.boost.org Sent: Nov 10, 2008 10:41 AM Subject: [Boost-users] [Database] question about database Hello: Is there a database boost implementation??.. or Have I do my own implementation? Thank you for all Salu2... _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users Sent from my Verizon Wireless BlackBerry

2 1

[Database] question about database
by Mario Chacon 10 Nov '08

10 Nov '08

Hello: Is there a database boost implementation??.. or Have I do my own implementation? Thank you for all Salu2...

1 0

[Reflextion] Please help me, i have trouble with reflextion
by Mario Chacon 10 Nov '08

10 Nov '08

Hello, I am trying to use boos-reflexion but I have this trouble in this thread: http://archives.free.net.ph/message/20080913.122428.8014a555.fi.html Hello. I downloaded boost.extensions from http://boost-extension.blogspot.com/?gclid=CNjp5dfJ2JUCFQsZQgod0mHbWg When I tried the first example (the shared_library one) in the tutorial, I realized that the macro BOOST_EXTENSION_EXPORT_DECL didn't prevent c++ name mangling for the example function. I had to add extern "C" before void manually. And in the second tutorial (the animals tutorial) BOOST_EXTENSION_TYPE_MAP_FUNCTION seems to be called, but when I get the map from main, it is empty. The library is found (LD_LIBRARY_PATH is set so that it finds the library) but it does not work. Thank you. Tested in gcc 4.3.2 under ubuntu 8.10. Can somebody help me ?

3 8

can't initialize boost::filesystem::path
by ahassaine＠gmail.com 10 Nov '08

10 Nov '08

Dear boot users, I'm using boost 1.33 with Visual C++ 7. I need to create an instance of boost::filesystem::path. I tried : > std::string dir="c:\\"; > boost::filesystem::path my_path(dir); The compilation is successful but at the execution, I obtain a non handled exception in the xstring file at the end of this function : > void _Tidy(bool _Built = false, > size_type _Newsize = 0) > { // initialize buffer, deallocating any storage > if (!_Built) > ; > else if (_BUF_SIZE <= _Myres) > { // copy any leftovers to small buffer and deallocate > _Elem *_Ptr = _Bx._Ptr; > if (0 < _Newsize) > _Traits::copy(_Bx._Buf, _Ptr, _Newsize); > _Mybase::_Alval.deallocate(_Ptr, _Myres + 1); > } > _Myres = _BUF_SIZE - 1; > _Eos(_Newsize); > } Any help is welcome. Thanks in advance !

2 2