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

Program Options of Filesystem Path's - confused!
by John Dlugosz 17 Aug '10

17 Aug '10

OK, If I take a po:wvalue<std::wstring>()->notifier(&datadir_set) the string gets passed to datadir_set, and within that function it implicitly converts the string to a fs::wpath instance to call set_me. It works as expected. void set_me (const fs::wpath& p); void datadir_set (const std::wstring& s) { wcout << L"** set data dir to " << s << L".\n"; set_me (s); } However, if I declare the program option as po::wvalue<fs::wpath>()->notifier(&set_me) then when it runs I get "invalid option value". It apparently can't convert the argv token into a wpath? But it's not a compile-time error so it thinks it knows how to, but gets an error actually doing it? I have no trouble passing long string literals to the constructor, e.g. fs::wpath f1 (L"C:\\here\\there.txt"); The program option takes "." on the command line just fine, so it's the specific value of the string it doesn't like! I tried with Unix-style slashes, with no difference. A little experimenting tells me that it doesn't like having spaces in the string! Note that the quotes are understood by the run-time library that calls main, so the whole string (without surrounding quotes) is present in one element of argv. It works just fine when taking the argument as a string. This seems like a bug, somewhere. --John TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

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[1.44.0] Release 1.44.0 is now available
by Beman Dawes 17 Aug '10

17 Aug '10

Release 1.44.0 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This release contains two new libraies (Meta State Machine & Polygon) and numerous enhancements and bug fixes for existing libraries. For details, including download links, see http://www.boost.org/users/download/version_1_44_0 The release can also be downloaded directly from SourceForge. See http://sourceforge.net/projects/boost/files/ To install this release on your system, see http://www.boost.org/doc/libs/release/more/getting_started/index.html Thanks, --The Boost release team Beman Dawes Daniel James Eric Niebler Rene Rivera Vladimir Prus

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Trac needs more milestones?
by Paul A. Bristow 17 Aug '10

17 Aug '10

I note that a milestone for the next version 1.45? isn't available yet for Trac tickets. Would it be useful to create a few 'spares' 1.45, 1.46, 1.47 ... to avoid this problem each release? I think there is a case for more than one release ahead - sometime one knows that testing time is going to mean it will miss the next release, so setting a milestone further ahead makes perfect sense. (Rare 1.n.1 cases can be added too if they prove necessary). (And/or does adding new milestones need to go the (endless?) list of release managers tasks?) Thanks. Paul --- Paul A. Bristow Prizet Farmhouse Kendal, UK LA8 8AB +44 1539 561830, mobile +44 7714330204 pbristow(a)hetp.u-net.com

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Program options: Set function for an option?
by Ingo Maindorfer 17 Aug '10

17 Aug '10

Hi! Let's assume we have this: (stolen from tutorial): // Declare the supported options. po::options_description desc("Allowed options"); desc.add_options() ("compression", po::value<int>(), "set compression level") ; po::variables_map vm; po::store(po::parse_command_line(ac, av, desc), vm); po::notify(vm); ... if (vm.count("compression")) { cout << "Compression level was set to " << vm["compression"].as<int>() << ".\n"; } else { cout << "Compression level was not set.\n"; } Is there a way to set a new int to "compression" programmatically like this: vm["compression"].set( 42 ) ? Best regards, Ingo

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[Log] Some questions on severity_logger usage
by Olivier Tournaire 17 Aug '10

17 Aug '10

Hi all, I am trying to use Boost.Log for my application. The log code is in shared library (a plugin). Here is how I set up my .so logging, according to the documentation: // ville_numerique_logging.hpp #include <boost/log/common.hpp> #include <boost/log/core.hpp> #include <boost/log/trivial.hpp> #include <boost/log/filters.hpp> #include <boost/log/formatters.hpp> #include <boost/log/utility/init/to_file.hpp> enum severity_level { normal, notification, warning, error, critical }; BOOST_LOG_DECLARE_GLOBAL_LOGGER_INIT(my_logger, boost::log::sources::severity_logger< >) { boost::log::init_log_to_file ( boost::log::keywords::file_name = "/home/olivier/ville_numerique.log", boost::log::formatters::attr< unsigned int >("LineID"), boost::log::keywords::format = "[%TimeStamp%]: %_%" // log record format ); // boost::log::core::get()->set_filter // ( // boost::log::filters::attr< boost::log::trivial::severity_level >("Severity") >= boost::log::trivial::info // ); return boost::log::sources::severity_logger< >(); } In some of my method, I then try lo log: src::severity_logger< >& lg = my_logger::get(); BOOST_LOG_SEV(lg, normal) << "A regular message"; BOOST_LOG_SEV(lg, warning) << "Something bad is going on but I can handle it"; BOOST_LOG_SEV(lg, critical) << "Everything crumbles, shoot me now!"; But, nothing happens. The file is not created. If I uncomment the set_filter lines, it throws an exception: "Requested attribute value not found" Could you please help? I am fighting with this for a too long time now. Regards, Olivier ----------------------------------------------------- Olivier Tournaire MATIS - Institut Géographique National 73, Ave de Paris 94165 St Mandé cedex, France tel: (+33) 1 43 98 84 29 fax: (+33) 1 43 98 85 81

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TypeError: No registered converter was able to extract a C++ pointer to type char from this Python object of type str
by Brian Ray 17 Aug '10

17 Aug '10

Hello: I think I am experience a build problem here but not really sure; nonetheless, below is a simple example that illustrates my problem. Any idea what I might be doing wrong. I am using boost_1_43_0 built with gcc 4.2.1 on i686 running darwin. I am linking to the standard 2.5 python that comes with the distro. Please note that the PyRun_SimpleString("import sys"); does not error at all. The error comes from when the call to import(). I am not sure if this is a clue or not but gdb seems not to know what line it is on. I am guessing it is just confused because of all the inlines. I suspect this is a linking issues of some sort. However I did check that they are all linking to the correct location. Why does it convert the const char * to a str in the first place. Seems to be thrashing around a bit. -- Brian /// contents of boost_python_issue.cpp #include <boost/python.hpp> using namespace boost::python; int main(int argc, char **argv) { Py_Initialize(); try { PyRun_SimpleString("import sys"); // This raises exception object sys = import("sys"); } catch (boost::python::error_already_set) { PyErr_Print(); } Py_Finalize(); } // Compiled with 'g++ -I. -I/usr/include -I/usr/local/include -I../../includes/python2_5_1 -g -L/usr/local/lib boost_python_issue.cpp -lboost_system -lboost_python -lm -lpython2.5 -o boost_python_issue' Output from gdb: (gdb) break main Breakpoint 1 at 0x100001319: file boost_python_issue.cpp, line 9. (gdb) r Starting program: /Project/zephyr/src/Composer/boost_python_issue Reading symbols for shared libraries .++++++++..... done Breakpoint 1, main (argc=1, argv=0x7fff5fbff6d8) at boost_python_issue.cpp:9 9 Py_Initialize(); (gdb) s 11 PyRun_SimpleString("import sys"); (gdb) 13 object sys = import("sys"); (gdb) boost::python::str::str (this=0x7fff5fbff690, s=0x10000169d "sys") at str.hpp:150 150 str(const char* s) : base(s) {} // new str (gdb) boost::python::detail::str_base::str_base (this=0x7fff5fbff690, s=0x10000169d "sys") at libs/python/src/str.cpp:39 39 )) (gdb) object [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/object_core.hpp:534 Line number 534 out of range; errors.hpp has 55 lines. (gdb) expect_non_null<PyObject> [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/errors.hpp:43 44 if (x == 0) (gdb) object [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/object_core.hpp:513 534 : object_base(expect_non_null((PyObject*)p)) (gdb) object_base [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/object_core.hpp:513 513 : m_ptr(p) (gdb) boost::python::detail::str_base::str_base (this=0x7fff5fbff690, s=<value temporarily unavailable, due to optimizations>) at libs/python/src/str.cpp:40 40 {} (gdb) 0x000000010000154d in boost::python::str::str (this=0x7fff5fbff690, s=0x10000169d "sys") at str.hpp:150 150 str(const char* s) : base(s) {} // new str (gdb) boost::python::import (name=@0x7fff5fbff690) at libs/python/src/import.cpp:19 19 char *n = python::extract<char *>(name); (gdb) extract [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/extract.hpp:156 156 # else (gdb) boost::python::api::object_base::ptr () at /Users/bray/sources/boost_1_43_0/boost/python/object_core.hpp:542 543 return m_ptr; (gdb) extract [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/extract.hpp:216 156 : base(o.ptr()) (gdb) extract_pointer [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/extract.hpp:216 219 ) (gdb) boost::python::converter::get_lvalue_from_python (source=0x1005cb1e0, converters=@0x100409500) at libs/python/src/converter/from_python.cpp:128 128 void* x = objects::find_instance_impl(source, converters.target_type); (gdb) boost::python::objects::find_instance_impl (inst=0x1005cb1e0, type={<boost::totally_ordered<boost::python::type_info,boost::python::type_info,boost::detail::empty_base<boost::python::type_info>,boost::detail::false_t>> = {<boost::totally_ordered1<boost::python::type_info,boost::detail::empty_base<boost::python::type_info> >> = {<boost::less_than_comparable1<boost::python::type_info,boost::equality_comparable1<boost::python::type_info, boost::detail::empty_base<boost::python::type_info> > >> = {<boost::equality_comparable1<boost::python::type_info,boost::detail::empty_base<boost::python::type_info> >> = {<boost::detail::empty_base<boost::python::type_info>> = {<No data fields>}, <No data fields>}, <No data fields>}, <No data fields>}, <No data fields>}, m_base_type = 0x7fff885a066c "c"}, null_shared_ptr_only=false) at libs/python/src/object/class.cpp:485 485 if (Py_TYPE(Py_TYPE(inst)) != &class_metatype_object) (gdb) 490 for (instance_holder* match = self->objects; match != 0; match = match->next()) (gdb) 497 } (gdb) boost::python::converter::get_lvalue_from_python (source=0x1005cb1e0, converters=@0x100409500) at libs/python/src/converter/from_python.cpp:129 129 if (x) (gdb) 132 lvalue_from_python_chain const* chain = converters.lvalue_chain; (gdb) 133 for (;chain != 0; chain = chain->next) (gdb) 135 void* r = chain->convert(source); (gdb) boost::python::converter::(anonymous namespace)::convert_to_cstring (obj=0x1005cb1e0) at libs/python/src/converter/builtin_converters.cpp:46 46 return PyString_Check(obj) ? PyString_AsString(obj) : 0; (gdb) 47 } (gdb) boost::python::converter::get_lvalue_from_python (source=0x1005cb1e0, converters=<value temporarily unavailable, due to optimizations>) at libs/python/src/converter/from_python.cpp:136 136 if (r != 0) (gdb) 132 lvalue_from_python_chain const* chain = converters.lvalue_chain; (gdb) 133 for (;chain != 0; chain = chain->next) (gdb) 140 } (gdb) 0x00000001001a1128 in extract_pointer [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/extract.hpp:219 219 ) (gdb) boost::python::import (name=<value temporarily unavailable, due to optimizations>) at libs/python/src/import.cpp:19 19 char *n = python::extract<char *>(name); (gdb) boost::python::extract<char*>::operator char* () at /Users/bray/sources/boost_1_43_0/boost/python/extract.hpp:138 138 return (*this)(); (gdb) boost::python::converter::extract_pointer<char*>::operator() () at extract.hpp:231 232 if (m_result == 0 && m_source != Py_None) (gdb) boost::python::converter::extract_pointer<char*>::operator() () at extract.hpp:233 233 (throw_no_pointer_from_python)(m_source, registered_pointee<Ptr>::converters); (gdb) boost::python::converter::throw_no_pointer_from_python (source=0x1005cb1e0, converters=@0x100409500) at libs/python/src/converter/from_python.cpp:256 256 (throw_no_lvalue_from_python)(source, converters, "pointer"); (gdb) 257 } (gdb) boost::python::converter::throw_no_pointer_from_python (source=0x1005cb1e0, converters=@0x100409500) at libs/python/src/converter/from_python.cpp:256 256 (throw_no_lvalue_from_python)(source, converters, "pointer"); (gdb) boost::python::converter::(anonymous namespace)::throw_no_lvalue_from_python (source=0x1005cb1e0, converters=@0x100409500, ref_type=0x1001a8e55 "pointer") at libs/python/src/converter/from_python.cpp:201 201 void throw_no_lvalue_from_python(PyObject* source, registration const& converters, char const* ref_type) (gdb) 215 )); (gdb) boost::python::type_info::name () at /Users/bray/sources/boost_1_43_0/boost/python/type_id.hpp:156 156 { (gdb) boost::python::detail::gcc_demangle (mangled=0x7fff885a066c "c") at libs/python/src/converter/type_id.cpp:116 116 static mangling_map demangler; (gdb) 121 , compare_first_cstring()); (gdb) std::vector<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::end () at /usr/include/c++/4.2.1/bits/stl_vector.h:349 349 inline bool (gdb) __normal_iterator [inlined] () at /usr/include/c++/4.2.1/bits/stl_iterator.h:654 817 { return __lhs.base() - __rhs.base(); } (gdb) std::vector<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::end () at /usr/include/c++/4.2.1/bits/stl_vector.h:331 331 { return iterator(this->_M_impl._M_start); } (gdb) boost::python::detail::gcc_demangle (mangled=0x7fff885a066c "c") at libs/python/src/converter/type_id.cpp:121 121 , compare_first_cstring()); (gdb) lower_bound<__gnu_cxx::__normal_iterator<std::pair<const char*, const char*>*, std::vector<std::pair<const char*, const char*>, std::allocator<std::pair<const char*, const char*> > > >, std::pair<const char*, const char*>, boost::python::<unnamed>::compare_first_cstring> [inlined] () at /usr/include/c++/4.2.1/bits/stl_algo.h:98 98 return __last - __first; (gdb) operator-<std::pair<const char*, const char*>*, std::vector<std::pair<const char*, const char*>, std::allocator<std::pair<const char*, const char*> > > > [inlined] () at /usr/include/c++/4.2.1/bits/stl_iterator_base_funcs.h:119 119 std::__iterator_category(__first)); (gdb) __distance<__gnu_cxx::__normal_iterator<std::pair<const char*, const char*>*, std::vector<std::pair<const char*, const char*>, std::allocator<std::pair<const char*, const char*> > > > > [inlined] () at /usr/include/c++/4.2.1/bits/stl_iterator_base_funcs.h:2948 Line number 2948 out of range; stl_iterator_base_funcs.h has 182 lines. (gdb) distance<__gnu_cxx::__normal_iterator<std::pair<const char*, const char*>*, std::vector<std::pair<const char*, const char*>, std::allocator<std::pair<const char*, const char*> > > > > [inlined] () at /usr/include/c++/4.2.1/bits/stl_iterator.h:116 156 __i += __n; (gdb) lower_bound<__gnu_cxx::__normal_iterator<std::pair<const char*, const char*>*, std::vector<std::pair<const char*, const char*>, std::allocator<std::pair<const char*, const char*> > > >, std::pair<const char*, const char*>, boost::python::<unnamed>::compare_first_cstring> [inlined] () at /usr/include/c++/4.2.1/bits/stl_algo.h:2952 2952 while (__len > 0) (gdb) boost::python::detail::gcc_demangle (mangled=0x7fff885a066c "c") at libs/python/src/converter/type_id.cpp:121 121 , compare_first_cstring()); (gdb) 123 if (p == demangler.end() || strcmp(p->first, mangled)) (gdb) 128 ); (gdb) 132 if (status == -1) (gdb) 143 : keeper.p; (gdb) 152 if (cxxabi_cxa_demangle_is_broken() (gdb) cxxabi_cxa_demangle_is_broken [inlined] () at /Users/bray/sources/boost_1_43_0/libs/python/src/converter/type_id.cpp:94 97 if (!was_tested) { (gdb) 99 free_mem keeper(cxxabi::__cxa_demangle("b", 0, 0, &status)); (gdb) 100 was_tested = true; (gdb) 101 if (status == -2 || strcmp(keeper.p, "bool") != 0) { (gdb) 103 } (gdb) ~free_mem [inlined] () at /Users/bray/sources/boost_1_43_0/libs/python/src/converter/type_id.cpp:86 87 std::free(p); (gdb) boost::python::detail::gcc_demangle (mangled=0x7fff885a066c "c") at libs/python/src/converter/type_id.cpp:152 152 if (cxxabi_cxa_demangle_is_broken() (gdb) 183 p = demangler.insert(p, std::make_pair(mangled, demangled)); (gdb) 331 { return iterator(this->_M_impl._M_start); } (gdb) 183 p = demangler.insert(p, std::make_pair(mangled, demangled)); (gdb) std::vector<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::insert () at /usr/include/c++/4.2.1/bits/vector.tcc:93 95 if (this->_M_impl._M_finish != this->_M_impl._M_end_of_storage (gdb) 102 _M_insert_aux(__position, __x); (gdb) std::vector<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::_M_insert_aux (this=0x1001bfd40, __position={_M_current = 0x0}, __x=@0x7fff5fbff5a0) at vector.tcc:245 245 _M_insert_aux(iterator __position, const _Tp& __x) (gdb) 247 if (this->_M_impl._M_finish != this->_M_impl._M_end_of_storage) (gdb) 260 const size_type __old_size = size(); (gdb) std::vector<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::size () at /usr/include/c++/4.2.1/bits/stl_vector.h:400 400 { return size_type(this->_M_impl._M_finish - this->_M_impl._M_start); } (gdb) std::vector<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::_M_insert_aux (this=0x1001bfd40, __position={_M_current = 0x0}, __x=@0x7fff5fbff5a0) at vector.tcc:261 261 if (__old_size == this->max_size()) (gdb) 267 size_type __len = __old_size != 0 ? 2 * __old_size : 1; (gdb) 88 if (__builtin_expect(__n > this->max_size(), false)) (gdb) 91 return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp))); (gdb) 275 __new_finish = (gdb) __uninitialized_copy_a<std::pair<const char*, const char*>*, std::pair<const char*, const char*>*, std::pair<const char*, const char*> > [inlined] () at /usr/include/c++/4.2.1/bits/stl_uninitialized.h:114 114 _Is_POD()); (gdb) __uninitialized_copy_aux<std::pair<const char*, const char*>*, std::pair<const char*, const char*>*> [inlined] () at stl_uninitialized.h:254 254 { return std::uninitialized_copy(__first, __last, __result); } (gdb) uninitialized_copy<std::pair<const char*, const char*>*, std::pair<const char*, const char*>*> [inlined] () at stl_uninitialized.h:254 254 { return std::uninitialized_copy(__first, __last, __result); } (gdb) __gnu_cxx::new_allocator<std::pair<char const*, char const*> >::construct () at /usr/include/c++/4.2.1/ext/new_allocator.h:107 107 { ::new(__p) _Tp(__val); } (gdb) std::vector<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::_M_insert_aux (this=0x1001bfd40, __position={_M_current = 0x0}, __x=@0x7fff5fbff5a0) at vector.tcc:280 280 ++__new_finish; (gdb) 281 __new_finish = (gdb) __uninitialized_copy_a<std::pair<const char*, const char*>*, std::pair<const char*, const char*>*, std::pair<const char*, const char*> > [inlined] () at /usr/include/c++/4.2.1/bits/stl_uninitialized.h:114 114 _Is_POD()); (gdb) __uninitialized_copy_aux<std::pair<const char*, const char*>*, std::pair<const char*, const char*>*> [inlined] () at stl_uninitialized.h:254 254 { return std::uninitialized_copy(__first, __last, __result); } (gdb) uninitialized_copy<std::pair<const char*, const char*>*, std::pair<const char*, const char*>*> [inlined] () at stl_uninitialized.h:254 254 { return std::uninitialized_copy(__first, __last, __result); } (gdb) std::vector<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::_M_insert_aux (this=0x1001bfd40, __position={_M_current = 0x0}, __x=<value temporarily unavailable, due to optimizations>) at vector.tcc:293 293 std::_Destroy(this->_M_impl._M_start, this->_M_impl._M_finish, (gdb) 295 _M_deallocate(this->_M_impl._M_start, (gdb) std::_Vector_base<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::_M_deallocate () at /usr/include/c++/4.2.1/bits/stl_vector.h:135 136 if (__p) (gdb) std::vector<std::pair<char const*, char const*>, std::allocator<std::pair<char const*, char const*> > >::_M_insert_aux (this=0x1001bfd40, __position={_M_current = 0x0}, __x=<value temporarily unavailable, due to optimizations>) at vector.tcc:298 298 this->_M_impl._M_start = __new_start; (gdb) 299 this->_M_impl._M_finish = __new_finish; (gdb) 300 this->_M_impl._M_end_of_storage = __new_start + __len; (gdb) boost::python::detail::gcc_demangle (mangled=0x7fff885a066c "c") at vector.tcc:103 103 return iterator(this->_M_impl._M_start + __n); (gdb) boost::python::detail::gcc_demangle (mangled=0x7fff885a066c "c") at libs/python/src/converter/type_id.cpp:183 183 p = demangler.insert(p, std::make_pair(mangled, demangled)); (gdb) 185 } (gdb) ~free_mem [inlined] () at /Users/bray/sources/boost_1_43_0/libs/python/src/converter/type_id.cpp:86 87 std::free(p); (gdb) boost::python::detail::gcc_demangle (mangled=0x7fff885a066c "c") at libs/python/src/converter/type_id.cpp:189 189 } (gdb) boost::python::converter::(anonymous namespace)::throw_no_lvalue_from_python (source=<value temporarily unavailable, due to optimizations>, converters=<value temporarily unavailable, due to optimizations>, ref_type=0x1001a8e55 "pointer") at libs/python/src/converter/from_python.cpp:215 215 )); (gdb) handle<PyObject> [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/handle.hpp:75 75 : m_p( (gdb) boost::python::detail::manage_ptr<_object> (p=0x1005ad6b8) at handle.hpp:55 55 inline T* manage_ptr(T* p, ...) (gdb) 57 return expect_non_null(p); (gdb) expect_non_null<PyObject> [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/errors.hpp:43 44 if (x == 0) (gdb) 0x000000010018a81d in boost::python::converter::(anonymous namespace)::throw_no_lvalue_from_python (source=<value temporarily unavailable, due to optimizations>, converters=<value temporarily unavailable, due to optimizations>, ref_type=0x1001a8e55 "pointer") at libs/python/src/converter/from_python.cpp:215 215 )); (gdb) boost::python::converter::(anonymous namespace)::throw_no_lvalue_from_python (source=<value temporarily unavailable, due to optimizations>, converters=<value temporarily unavailable, due to optimizations>, ref_type=0x1001a8e55 "pointer") at libs/python/src/converter/from_python.cpp:217 217 PyErr_SetObject(PyExc_TypeError, msg.get()); (gdb) 219 throw_error_already_set(); (gdb) boost::python::throw_error_already_set () at libs/python/src/errors.cpp:61 61 throw error_already_set(); (gdb) error_already_set [inlined] () at /Users/bray/sources/boost_1_43_0/boost/python/errors.hpp:19 19 virtual ~error_already_set(); (gdb) boost::python::throw_error_already_set () at libs/python/src/errors.cpp:61 61 throw error_already_set(); (gdb) TypeError: No registered converter was able to extract a C++ pointer to type char from this Python object of type str Program exited normally.

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Program Options - help display
by John Dlugosz 16 Aug '10

16 Aug '10

cout << opt; displays a formatted report using some built-in width. How can I make it appreciate the actual width of the command window instead? The formatting leaves much to be desired if default values are included. The description is forced into a very narrow column. --John TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

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Function or Bind question
by John Dlugosz 16 Aug '10

16 Aug '10

The command-line-argument library has a callback function 'notifier' used like this: po::wvalue<std::wstring>()->notifier(&foo) If I write void foo (const std::wstring& s) { C::bar(s); } it works fine. wstring and void are the template arguments to the function object. Now if I write notifier(&C::bar) instead, I get a huge spiel of compiler errors. Yet, from the body of foo you can see that s can be implicitly converted to the type of bar's argument (const boost::filesystem::wpath&) and the return type is also void. I thought that generalized functions objects pretty much worked that if you can write the call in normal code, it makes the correct wrapper to do that. What am I missing? --John TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

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32- and 64-bit builds on same machine
by Johan Råde 16 Aug '10

16 Aug '10

Hi, What is the most convenient way to build Boost if I need both 32- and 64-bit builds on the same Windows machine? I could of course install two separate copies of the entire Boost source tree, and build one from the 32-bit Visual studio command prompt, and the other from the 64-bit Visual Studio command prompt. But that seems a bit wasteful. I tried building from the same source tree twice, once using the 32-bit command prompt and once using the 64-bit command prompt, but that did not work. (Nothing happened during the second build.) Thank you, Johan Råde

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Problem with simple type extraction
by Christian Henning 16 Aug '10

16 Aug '10

Hi there, I cannot understand why the code below gives me a static assertion. As far as I know I use a very common technique to to extract a type from templated class using specialization over this class. #include <boost/assert.hpp> #include <boost/type_traits/is_same.hpp> #include <boost/gil/gil_all.hpp> namespace boost { namespace gil { template< typename T > struct bit_field_type{ typedef T type; }; template< typename BitField, typename ChannelBitSizes, typename Layout, bool IsMutable > struct bit_field_type< bit_aligned_pixel_reference< BitField , ChannelBitSizes , Layout , IsMutable > > { typedef BitField type; }; } // namespace gil } // namespace boost int main(int argc, char* argv[]) { typedef boost::gil::bit_aligned_image1_type< 1, boost::gil::gray_layout_t >::type gray1_image_t; typedef gray1_image_t::view_t::reference ref; typedef boost::gil::bit_field_type< ref >::type bit_field_t; BOOST_STATIC_ASSERT(( boost::is_same< bit_field_t, unsigned char >::value )); return 0; } The type for gray1_image_t::view_t::reference is the following: boost::gil::bit_aligned_pixel_reference< unsigned char, boost::mpl::vector1_c< unsigned int, 1 > , boost::gil::layout< boost::mpl::vector1< boost::gil::gray_color_t >, boost::mpl::range_c< int, 0, 1> > , 1 > Can somebody tell what wrong. I have been staring at this for too long. I'm using MS Visual Studio 9 and 10. Thanks in advance, Christian

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