March 2010 - Boost-users - lists.preview.boost.org

boost::filesystem directory_iterator: how to get the last file of a directory ?
by Vial, Florent 12 Mar '10

12 Mar '10

Hi boost-users, I am using a recursvive function for iterating over a starting path. When i finally arrive in a directory that contains no subdirectory (what i call a "final" directory), i want to retrieve the first and the last file of this directory. I succeed in retrieving the first file of the final directory (see code snippet below), But i do not know how to retireve the last one using the same directory iterator. Can someone think of an elegant solution ? ------------------ CODE BEGIN ------- namespace fs = boost::filesystem; void my_function (const fs::path &ph) { bool firstFileOfFinalDir = false; if (fs::is_directory(ph)) { fs::directory_iterator end_iter; for (fs::directory_iterator dir_itr(ph); dir_itr != end_iter; ++dir_itr) { if (fs::is_directory(dir_itr->status())) { // Recursive call my_function(fs::path(dir_itr->path())); } else { // We are in a "final" directory if (fs::is_regular_file( dir_itr->status())) { if (firstFileOfFinalDir) { // Do something with the first file of the final directory firstFileOfFinalDir = false; } else { // My problem : how to check if // dir_itr == (end_iter - 1) // i.e. if it is the last valid value ? } } } } } } ------------------ CODE END ------- Thank you in advance for your help, Florent Be a part of filmmaking's exciting future today by registering your intent to purchase on: www.arridigital.com Arnold & Richter Cine Technik GmbH & Co. Betriebs KG Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRA 57918 Personlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRB 54477 Geschaftsfuhrer: Franz Kraus; Dr. Martin Prillmann

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Nested regex results with xpressive.
by Surya Kiran Gullapalli 12 Mar '10

12 Mar '10

Hello all, I'm trying to match a string with xpressive. The match is fine, but the nested results doesn't seem to be working. The code is here<http://pastebin.com/TLSiRMRh> my regex *combinedReg* is made up of 3 sregex objects. Two of them store the results using mark_tag objects. When I try to match the string, I get a complete match and toplevel match says it has 3 nested results. Which is correct. When I try to loop over those three nested results for more nested results, I get nothing. what am I doing wrong? Thanks in advance, Surya

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[fusion] transform & iterators
by David A. Greene 12 Mar '10

12 Mar '10

For the first attached testcase, can anyone explain why "Doesn't" doesn't? I would not expect the second test to compile. But is there some way to bridge the gap between fusion iterators, boost.Range ranges and standard iterators? Is there any way to turn a fusion iterator into a standard- conforming iterator? -Dave

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matrix iterator each element
by Kraus Philipp 12 Mar '10

12 Mar '10

Hello, I have very large matrices (not sparse), where I have to change each element. From the documentation I used the example with which two for-loops. I use for vectors: blas::vector<T> l_vec = p_vec; BOOST_FOREACH( T& i, l_vec) i = std::pow(i, p_exponent); Is there any way to process each element in the matrix with a loop and an iterator? Thanks Phil

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boost::regex on to match in the middle of a string
by Conoscenza Silente 12 Mar '10

12 Mar '10

Hi All I am newbie to boost::regex. I have a string including multiple new lines characters in it like the one below. "this is a big string\nthat I would like\ntoParse here: WORD_TO_FIND=Ciao\nin the middle" I tried the following regex but it doesn't match. boost::regex ln0("WORD_TO_FIND=\t(?<SYMBOL>\\w+).+", boost::regex::perl ); Do you know what is the option and how to set it up to enable the matching for an entire string and not line by line? Thanks

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permutation_iterator documentation error
by Paul 12 Mar '10

12 Mar '10

I tried to enter this into the bug database, but it said "Database Locked" http://www.boost.org/doc/libs/1_42_0/libs/iterator/doc/permutation_iterator… this: ElementIterator const& base() const; should read: IndexIterator const& base() const;

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Boost 1.39.0 unit test crash on Sun OS
by Yogesh Arora 12 Mar '10

12 Mar '10

Hi I have just started using boost unit test framework and i am also new to boost. I have a very basic test case program which i am testing with boost 1.39.0 unit test libraries. The code compiles properly but on running it crashes without even reaching my test case. Is someone facing similar issue on Sun OS. Btw, I am using Boost 1.39.0 on Sun os. I have compiled boost libraries myself with sun toolset using these options ./bootstrap.sh --with-toolset=sun wih user.config.jam as using sun : 5.9 : /bb/util/common/studio12-v4/SUNWspro/bin/CC : <stdlib>sun-stlport <cxxflags>"-library=stlport4 -xcode=pic32 -erroff=wvarhidemem,hidevf,hidevfinvb,badargtypel2w,wbadinitl,nullref,temwhileinst,unassigned -errtags=yes" <linkflags>"-library=stlport4 -xcode=pic32" ; Thanks Yogesh

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Re: [Boost-users] [Regex] Accessing match count
by ninti＠internode.on.net 12 Mar '10

12 Mar '10

Thanks Gevorg, that worked a treat. Actually, I don't really need the count as a string so this worked even better: return std::distance( boost::sregex_iterator( word.begin(), word.end(), expression ), boost::sregex_iterator() ); First time I've seen std::distance. Sigh, so much to learn ... :-) Mick

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Re: [Boost-users] boost::regex on to match in the middle of a string
by ninti＠internode.on.net 12 Mar '10

12 Mar '10

I'm a C++ and Boost newbie, and no regex guru, so don't quote me either :-) One thing I notice in your expression is a \t character following the =. Isn't that only going to match a tab? The boost::regex flag 'match_not_dot_newline' might be relevant, but since this flag must be explicitly set, it looks like dots match newlines by default. Would something as simple as this work (assuming dots match newlines)?: boost::regex ln0("WORD_TO_FIND=(.*)$", boost::regex::perl ); This assumes that the match you're looking for runs to the end of the string, which isn't clear. I'm also not clear if you want to match a single word or multiple words. Would stripping out newlines and replacing them with spaces first (or even later) help? Mick On Fri 12/03/10 10:32 AM , OvermindDL1 overminddl1(a)gmail.com sent: > On Thu, Mar 11, 2010 at 10:54 AM, Conoscenza Silente > wrote:> Hi All > > I am newbie to boost::regex. > > I have a string including multiple new lines > characters in it like the one> below. > > > > "this is a big string\nthat I would > like\ntoParse here:> WORD_TO_FIND=Ciao\nin the > middle"> > > I tried the following regex but it doesn't > match.> > > boost::regex > ln0("WORD_TO_FIND=\t(?\\w+).+", boost::regex::perl > );> > > Do you know what is the option and how to set it > up> to enable the matching for an entire string and > not line by line? > Do not quote me, I am not that knowledgeable about regex, but give > this a try, add a g\ to the beginning of your parsing line, or \g or > \g\ or something like that, I think it means global... > _______________________________________________ > Boost-users mailing list > B > oost-users@lists.boost.orghttp://lists.boost.org/mailman/listinfo.cgi/boost-users > >

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Boost unit test usage compile error
by Yogesh Arora 12 Mar '10

12 Mar '10

I am using Boost 1.39.0 on sun using sun cc compiler 5.9. I have written a simple test case which used boost unit test in included manner. The test file is #define BOOST_TEST_MAIN #define BOOST_TEST_MODULE example #include <boost/test/included/unit_test.hpp> BOOST_AUTO_TEST_CASE( test1 ) { BOOST_CHECK( true ); } i get this compilation error. I cant figure out what it means. Can someone please help me in this case boost_1_39_0/boost/test/impl/unit_test_main.ipp", line 113: Error: Could not find a match for std::vector<boost::unit_test::test_case_filter::single_filter>::vector(boost::unit_test::basic_string_token_iterator<char, boost::unit_test::ut_detail::default_char_compare<char>>, boost::unit_test::basic_string_token_iterator<char, boost::unit_test::ut_detail::default_char_compare<char>>) needed in boost::unit_test::test_case_filter::test_case_filter(boost::unit_test::basic_cstring<const char>). "/home/yarora/boost_1_39_0/boost/test/impl/unit_test_main.ipp", line 113: Error: Formal argument x of type const std::vector<boost::unit_test::test_case_filter::single_filter>& in call to std::vector<std::vector<boost::unit_test::test_case_filter::single_filter> >::push_back(const std::vector<boost::unit_test::test_case_filter::single_filter>&) is being passed int. 2 Error(s) detected. Yogesh

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