August 2008 - Boost-users - lists.boost.org

boost logger problem.
by lakers fan 29 Aug '08

29 Aug '08

Hello, Boost logger has a Macro BOOST_LOG_INIT that takes only one parameter "format" and not two as mentioned in the documentation. The log level is initialized to 0. When I tried to log some messages using BOOST_LOG_UNFORMATTED Macro with log level 0, there is no log in the file. Its an empty file altogether. Can someone help. Thanks, Lakers. _________________________________________________________________ See what people are saying about Windows Live. Check out featured posts. http://www.windowslive.com/connect?ocid=TXT_TAGLM_WL_connect2_082008

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[Regex] compiling for Windows Mobile
by Paul Heil 29 Aug '08

29 Aug '08

I'm trying to compile the Boost 1.36.0 regex library for Windows Mobile 5.0 using Visual Studio 2008. But, I run in to a problem with STLPort (below): compile-c-c++ bin.v2\libs\regex\build\msvc-WM5\debug\link-static\runtime-link-static\stdlib-stlport\threading-multi\c_regex_traits.obj c_regex_traits.cpp Unknown EVC++ compiler version - please run the configure tests and report the results libs\regex\src\..\src\c_regex_traits.cpp(54) : error C2039: 'strxfrm' : is not a member of 'stlpd_std' libs\regex\src\..\src\c_regex_traits.cpp(54) : error C3861: 'strxfrm': identifier not found libs\regex\src\..\src\c_regex_traits.cpp(54) : fatal error C1903: unable to recover from previous error(s); stopping compilation The STLPort-5.1.5 <cstring> library has ifdef'd these out for Windows Mobile (below): # if !defined (_STLP_WCE) // these functions just don't exist on Windows CE using _STLP_VENDOR_CSTD::strcoll; using _STLP_VENDOR_CSTD::strerror; using _STLP_VENDOR_CSTD::strxfrm; # endif Is there anything I can do to fix this without breaking the Regex library? Thanks, PaulH

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[tr1|fusion]at_c<N>() tuple copying problem
by Markus Werle 29 Aug '08

29 Aug '08

Hi! The following piece of code yields "( 0)" as output, but IMHO the output should be "(test 1)". Looks like at_c creates temporaries, but I expected it to return a reference. How can I fix this? Markus #include <boost/spirit/include/phoenix_core.hpp> #include <boost/spirit/include/phoenix_fusion.hpp> #include <boost/tr1/tuple.hpp> #include <string> #include <iostream> namespace fusion = boost::fusion; namespace phoenix = boost::phoenix; int main() { typedef fusion::tuple<std::string, int> tuple_t; typedef std::tr1::tuple<std::string, int> tr1_tuple_t; tuple_t t("test", 1); tr1_tuple_t tr1_t; phoenix::at_c<0>(tr1_t) = phoenix::at_c<0>(t); phoenix::at_c<1>(tr1_t) = phoenix::at_c<1>(t); std::cout << tr1_t << std::endl; }

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Command line for building under vc9
by Sean Farrow 29 Aug '08

29 Aug '08

Hi: I need to build boost under vc 9.0. how do I specify an alternate vdersion of the compiler, I already have vc8 installed. Which compiler will be automatically picked up? Cheers Sean. __________ Information from ESET NOD32 Antivirus, version of virus signature database 3397 (20080828) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

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[thread] stupid question
by Johan Råde 29 Aug '08

29 Aug '08

What is the correct syntax to make the current thread sleep for 5 seconds? --Johan Råde

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[logging] Library status?
by Allen Cronce 29 Aug '08

29 Aug '08

Hi all, I'm experimenting with John Torjo's proposed logging library. According to a post by John to this mailing list in May, he was interested in having the third review by August. Did the review happen? What's the status of the logging library? Best, -- Allen Cronce

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boost - newbie question - remove files
by H H 29 Aug '08

29 Aug '08

Hi, I'm new to boost. Can I remove some files from the boost directory and keep only what I need? Will that work and it's license for? Thanks. boost\lib boost/function.hpp functional boost/preprocessor/iterate.hpp boost/detail/workaround.hpp boost/bind.hpp boost/shared_ptr.hpp boost/regex.hpp boost::smatch boost::regex_search boost::regex boost::regbase::no_except

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multi_array, resize and remove a row
by gast128 29 Aug '08

29 Aug '08

Dear all, this is yet another post on multi_array. It seems possible that the multi_array's are resizable (using default construction :( ). However we have no the problem that a specific row should be removed (which is not necessarily the last row). Using the resize option it seems not possbile. Am I correct? Wkr.

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[spirit2] push_back not fully understood - vc8 rejects code, why?
by Markus Werle 29 Aug '08

29 Aug '08

> Hi! Though I appreciate simple examples in the docs it is indeed helpful to have examples with fully qualified names. I am having hard times figuring out which versions of "_1", "at_c", etc. are in use. the fusion/phoenix/proto/mpl chaos is hard to keep track of. In summary: using declaratives are nice for toy examples but drive you nuts, once you #include more files and have ADL destroying the idyll of simplicity. Below is a piece of code that nearly compiles. One line has a problem: A semantic action, namely a push_back fails under vc8 and the error message is far from being helpful. So could you please be so nice and give me some hint on how to fix this. (BTW, Joel: "iter+30" directives from the spirit2 examples are assert-catched by the VC8 debugging STL, so I changed that part a little bit to first check the distance and doing iterator arithmetics afterwards. See below.) best regards, Markus ---snip--- #define BOOST_SPIRIT_DEBUG_OUT std::cerr #define BOOST_SPIRIT_DEBUG #include "Enforce.h" #include <boost/tr1/functional.hpp> #include <boost/tr1/tuple.hpp> #include <boost/mpl/assert.hpp> #include <boost/mpl/at.hpp> #include <boost/config/warning_disable.hpp> #include <boost/spirit/include/qi.hpp> #include <boost/spirit/include/phoenix_core.hpp> #include <boost/spirit/include/phoenix_operator.hpp> #include <boost/spirit/include/phoenix_fusion.hpp> #include <boost/spirit/include/phoenix_stl.hpp> #include <boost/spirit/include/phoenix_container.hpp> #include <boost/fusion/include/adapt_struct.hpp> #include <boost/variant/recursive_variant.hpp> #include <boost/foreach.hpp> #include <boost/preprocessor/repetition.hpp> #include <boost/preprocessor/arithmetic/sub.hpp> #include <boost/preprocessor/punctuation/comma_if.hpp> #include <list> #include <string> #include <vector> #include <iostream> #include <iterator> using namespace boost::spirit; using namespace boost::spirit::qi; using namespace boost::spirit::ascii; using namespace boost::spirit::arg_names; using boost::phoenix::push_back; namespace fusion = boost::fusion; namespace phoenix = boost::phoenix; namespace { //////////////////////////////////////////////////////////////////////////////// // parser traits struct parser_traits { template <typename T, int Dummy = 0> struct parser; #define PARSER_TRAITS(TYPE, PARSER_T) \ template <int Dummy> struct parser<TYPE, Dummy> \ { \ typedef PARSER_T type; \ \ static inline \ PARSER_T p() \ { \ PARSER_T result; \ return result; \ } \ } // int PARSER_TRAITS(int, int_type); // unsigned int PARSER_TRAITS(unsigned int, uint_type); // double PARSER_TRAITS(double, double_type); }; //////////////////////////////////////////////////////////////////////////////// // parser template <typename Iterator, typename Tuple> struct tuple_grammar; template <typename Iterator, typename T1, typename T2> struct tuple_grammar<Iterator, std::tr1::tuple<T1, T2> > : grammar<Iterator, std::list<std::tr1::tuple<T1, T2> >(), space_type> { typename parser_traits::parser<T1>::type p1; typename parser_traits::parser<T2>::type p2; typedef typename std::tr1::tuple<T1, T2> tuple_t; tuple_grammar() : tuple_grammar::base_type(rule_tuple_list) { using phoenix::at_c; using boost::spirit::arg_names::_1; // using boost::spirit::container::push_back; using boost::phoenix::push_back; rule_tuple = '(' >> p1[at_c<0>(_val) = _1] >> ',' >> p2[at_c<1>(_val) = _1] >> ')' ; rule_tuple_list = // COMPILER FALS ON THIS SEMANTIC ACTION - WHY? *(rule_tuple[push_back(ref(_val), _1)]) ; } rule<Iterator, tuple_t(), space_type> rule_tuple; rule<Iterator, std::list<tuple_t>(), space_type> rule_tuple_list; }; //////////////////////////////////////////////////////////////////////////////// // string_to_list_of_tuples template <typename Tuple> struct string_to_list_of_tuples; template <typename T1, typename T2> struct string_to_list_of_tuples<std::tr1::tuple<T1, T2> > { typedef std::tr1::tuple<T1, T2> tuple_t; static std::list<tuple_t> apply(std::string const & s) { std::list<tuple_t> result; typedef tuple_grammar<std::string::const_iterator, tuple_t> tuple_grammar; tuple_grammar tg; std::string::const_iterator iter = s.begin(); std::string::const_iterator end = s.end(); bool r = phrase_parse(iter, end, tg, result, space); if (r && iter == end) { std::cout << "-------------------------\n"; std::cout << "Parsing succeeded\n"; std::cout << "-------------------------\n"; } else { std::size_t dist = std::distance(iter, end); std::string::const_iterator some = dist > 30 ? iter+30 : end; std::string context(iter, some); std::cout << "-------------------------\n"; std::cout << "Parsing failed\n"; std::cout << "stopped at: \"" << context << "...\"\n"; std::cout << "-------------------------\n"; } return result; } }; } // namespace int main() { try { { typedef std::tr1::tuple<int, int> tuple_t; std::list<tuple_t> test = string_to_list_of_tuples<tuple_t>::apply (" ( 1, 2 ) ( 3, 4)(5,6)"); std::copy(test.begin(), test.end(), std::ostream_iterator<tuple_t>(std::cout, "\n")); } // { // typedef std::tr1::tuple<unsigned int, int, double> tuple_t; // std::list<tuple_t> test = // string_to_list_of_tuples<tuple_t>::apply // (" ( 1, -2 , 5.123) ( 3, 4,7.9)(5,6,8.6789)"); // std::copy(test.begin(), test.end(), // std::ostream_iterator<tuple_t>(std::cout, "\n")); // } } catch (std::exception const & e) { std::cerr << e.what() << std::endl; } }

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[filesystem] Catching permissions errors?
by Allen Cronce 29 Aug '08

29 Aug '08

Hi all, I need to programmatically test for permissions errors during path iteration. I think what I need to do is catch the filesystem exception, then drill out the error code and compare it to the permission_denied error value. Here's a code fragment written under boost 1.35 that demonstrates what I'm talking about: try { // Force a permissions error on *nix machines when not running as root. // Note that this code is is for demonstration purposes only. Assume that // in the real implementation I'm doing something else here with the // filesystem that *might* throw a permissions error. boost::filesystem::path testDirPath( "/usr/local/cant_touch_this" ); create_directory(testDirPath); } catch(const boost::filesystem::filesystem_error& e) { // Check the error code to see if it's a permissions error if (boost::system::posix_error::permission_denied == e.code().value()) { std::cout << "The error code indicates a permissions error, as expected. " << std::endl; } else { std::cout << "Hmm... I didn't get a permissions error. That's wrong." << std::endl; } } Is this basically the right approach? Note that one concern I have is maintainability. A coworker wrote similar code to the above, but under boost 1.33.1. That code broke under 1.35 due to significant changes to the filesystem exceptions mechanism. I understand that there are no guarantees moving forward to new boost versions. I knew the job was dangerous when I took it ;-) But if there's anything I can do today to future-proof a little bit, that would be great. Thanks in advance for any feedback or suggestions. Best, -- Allen Cronce

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