February 2008 - Boost-users - lists.preview.boost.org

Statechart serialization
by mbrodeur65 04 Mar '15

04 Mar '15

Hi, I'm looking for a solution to serialize boost::statechart objects. I'm aware that this feature is on the statechart library todo list but was wondering if there are any workaround to achieve this with the latest boost release (1.34) ? thanks for your help ! mbrodeur65 -- View this message in context: http://www.nabble.com/Statechart-serialization-tf4131326.html#a11749139 Sent from the Boost - Users mailing list archive at Nabble.com.

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[Statechart] How to decide between post_event and process_event atrun time ?
by Philippe DAVID 22 Jul '14

22 Jul '14

Hi, I have a method in which I want to post/process an event. The thing is, this method can be called from outside the state machine (so I need to call process_event), or indirectly by a reaction of the state machine (in this case I must call post_event since process_event is not reentrant). I don't want to write 2 distinct methods to do this (one that calls post, and the other process), I would much rather prefer adding a 'if' in my method that tells me if I have to call process_event or post_event (if I'm being called indirectly by the state machine or not). Is there a way to do this with statechart ? regards, Philippe

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[asio] resolver::cancel() problem
by Matthew Edwards 14 Mar '14

14 Mar '14

In my application (and a separate test program) it seems as though the cancel() function on the resolver does not work as intended. For async resolves, the cancel functionality should abort them immediately and pass an 'operation aborted' error code to the callback handler. In my tests, I will resolve an invalid domain (this causes the resolve to take a few seconds, to demonstrate the problem), sleep for 100ms, then call cancel on the resolver object. No cancelling actually occurs, and the callback is simply triggered after a few seconds with a "No host found" error code, not the expected operation aborted. Has anyone experienced this before, or know how I might be using the resolver incorrectly?

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[multi_array] operator= requires resize - why?
by Markus Werle 04 Jun '12

04 Jun '12

Hi! IMHO the behaviour of operator= for multi_array is a little bit broken. A lot of preconditions required: template <typename ConstMultiArray> multi_array_ref& operator=(const ConstMultiArray& other) { [...] // make sure the dimensions agree assert(other.num_dimensions() == this->num_dimensions()); assert(std::equal(other.shape(),other.shape()+this->num_dimensions(), this->shape())); Besides the fact that I get mad about asserts instead of exceptions (please change this to a way users may choose) why do we have such an odd behaviour here? >From page 1, line 3 of the docs I cite: "The interface design is in line with the precedent set by the C++ Standard Library containers" - this is not true for operator=, since std::<container>::operator= works fine for me all the time _without_ any resize. Could we please change the behaviour of multi_array::operator= to take care of resize where in need to? IMHO operator= should result in a true copy ignoring previous state. Markus

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Newbie question
by Michael Qi 07 Dec '09

07 Dec '09

Hi, I am trying to start to learn boost. Now, I am learning the getting started guide. And try to build a boost regex program in the guide. But Visual C++ 7.1 tell me error: LINK : fatal error LNK1104: Could not open file "D:\Program.obj" Could you help me? Thank you

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[Math Toolkit] Gamma Distribution
by Christian Henning 21 Jul '09

21 Jul '09

Hi there, the documention of the gamma distribution talks about two different forms. How can can generate the second one with shape=1 and scale=1? I know how to get the first form: boost::math::gamma_distribution<> dist( 1, 1 ); I don't see how to get the second one? Thanks, Christian

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Design for boost::serialization of STL iterators.
by Carlo Wood 23 May '09

23 May '09

On Sat, Mar 11, 2006 at 11:45:36PM +0200, Peter Dimov wrote: > Carlo Wood wrote: > > > 1) WHY does boost::serialization not support serialization > > of iterators? > > It's very hard, if not impossible, in general. It is either impossible or possible. When it is possible, it can't be hard :p I think that at the moment of serialization, the actual container needs to be known. So, only concentrating on the syntax of the code that serializes an iterator, the following cannot work: ar & iter; However, the container will be known at that point (or at least, we might as well assume that). Therefore, I could imagine a syntax like: ar & foobar(container, iter); where 'foobar' is some template function (that will be part of boost::serialization in the future). Lets start with the last one (have to start somewhere). In order to deserialize the iterator (and taken into account that we already have the container) -- which makes me think that it might be better to pass a functor to operator& above. In other words, (at least for writing), use: template<class Container> struct Foobar { Foobar(Container const&, typename Container::const_iterator& iter) : M_container(container), M_iter(iter); private: Container const& M_container; Container::const_iterator& M_iter; }; and then assign to M_iter, whatever we find in M_container. > If you have access to the container to which the iterator i refers: > > a) if the container is a map, you can serialize i->first, then on > deserialization look up the key in the map using .find(); > > b) if the container is a sequence, and it has the same contents on > deserialization as it does on serialization, you can serialize the index of > the element - distance( c.begin(), i ). I don't think that it is a requirement that the whole container has to be read: either it's a map or set, in which case later insertions will not invalidate the container, or it is a vector, in which case we use an index, from which we can construct the end iterators before the whole container is reconstructed. Therefore, the following syntax can work imho: ar & FooBar(container, iter); Would you agree? There are a zillion questions and implementation details open - but I'd like to get anyones feedback about this type of interface for iterators before continuing. Current questions: What is a good name for Foobar? Am I right when I think that Foobar needs to be declared in boost::serialization? Now the hard part (for me) is that part that involves the internals of the boost library. At the moment one tries to serialize an iterator, it is possible (though not necessarily) that the object that the iterator points to is already serialized. In the case that we are dealing with an associative container (map or set etc), we don't want to store the contents of the object (or key part, in the case of a map) again: I'd like to just store that once, and store a reference in the archive at the other place. How can I make the library store an object only the first time and the store a reference the second time? This would be for an object of arbitrary type thus. I think that it is only feasible to do this when it's actually the same object (same memory address), which is the case; but while storing the object element of the container, the address of it isn't stored as well, is it? Is there a way to make: std::set<SomeData> s; [...] ar << s; Store the address of s (&s) along with the contents of s? And would that then automatically cause the library to not store that same object again when I do: std::set<SomeData>::iterator iter = s.find(...); [...] ar << *iter; Because then, &*iter would again be the same memory address as what was stored before. -- Carlo Wood <carlo(a)alinoe.com>

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[BGL] citing the Boost Graph Library
by Alejandro Marcos Aragón 06 May '09

06 May '09

Can anyone point me how to cite the Boost Graph Library in a paper? Is there any information in the boost website? Thank you all, Alejandro Aragón

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[date_time] posix_time::time_duration::operator<< fails for hours>23
by Soren Dreijer 04 Feb '09

04 Feb '09

I'm creating a posix_time::time_duration object based on the minutes() helper function. If I specify a large value, such as 2000, I get a time_duration of 33:20:00. Take a look at the following piece of code, though: time_duration td = minutes(2000); cout << to_simple_string(td); // OK cout << td; // Fails with an assertion in VS2008 The latter call fails with the following assertion in strftime.c on line 658: _VALIDATE_RETURN( ( ( timeptr->tm_hour >=0 ) && ( timeptr->tm_hour <= 23 ) ), EINVAL, FALSE) Apparently, operator<< expands to _expandtime(), which doesn't allow values for the hour to be greater than 23. Is this intended behavior, or should I just always use to_simple_string() rather than the convenient operator<< ?

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boost::program_options
by Duy Nguyen 09 Oct '08

09 Oct '08

When I try to use the boost::program_options library to read a property file, I got the error when I run "make" on Cygwin (I installed Cygwin on WIndows XP). > make g++.exe -I /cygdrive/c/MyTest/Test1/include/boost-1_34_1/ -c TestInit.cpp Test.cpp TestDriver.cpp g++.exe -I /cygdrive/c/MyTest/Test1/include/boost-1_34_1/ -c TestInit.cpp Test.cpp TestDriver.cpp g++.exe -I /cygdrive/c/MyTest/Test1/include/boost-1_34_1/ -c TestInit.cpp Test.cpp TestDriver.cpp g++.exe TestInit.o Test.o TestDriver.o -o "TestDriver" -L/cygdrive/c/MyTest/Test1/lib -lboost_program_options-gcc34-mt-d-1_34_1 -lg2c Info: resolving vtable for boost::program_options::variables_mapby linking to __imp___ZTVN5boost15program_options13variables_mapE (auto-import) Then when I run my program, it does not work. If I comment out the "try ... catch" block which uses the boost::propram_options library then it compiles and works fine. Please show me how to fix it. Thank you.

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boost::filesystem exception not caught on MacOS X
by Lothar May 21 Sep '08

21 Sep '08

Hi, I have a strange problem that an exception thrown by a boost::filesystem directory_iterator is not caugth on MacOS X. Please consider the following code: ("const string &dir" is a parameter) bool retVal = true; try { directory_iterator i(dir); directory_iterator end; while (i != end) { // do something ++i; } } catch (...) { retVal = false; } While this works perfectly on Windows and Linux (the exception is caught fine), on MacOS I get the following: terminate called after throwing an instance of 'boost::filesystem::basic_filesystem_error<boost::filesystem::basic_path<std::string, boost::filesystem::path_traits> >' what(): boost::filesystem::basic_directory_iterator constructor Abort trap The program runs fine (withouth the trap) if I comment out the upper lines. I use the boost 1.34.0 lib built as universal binary on MacOS 10.5, according to the instructions at http://svn.boost.org/trac/boost/wiki/CMakeConfigAndBuild I link to the static non-debug mt version of boost_filesystem. Exceptions within my program are caught fine, just this boost exception is not caught. The program is also compiled as non-debug. Any help would be very much appreciated. Regards, Lothar

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Boost Graph Library and Boehm Garbage Collector
by FBSL 08 Sep '08

08 Sep '08

Hello I am having trouble to garbage-collect adjacency_list<>. I have instanciated it with correctly garbage-collected vectors and lists (I have copied vecS and listS definitions, and added Boehm GC's default allocator so that they are garbage-collected). In my application I need to dynamically allocate many graphs, but it does not work, there is a (big) memory leak. Unfortunately, there is no template argument in adjacency_list<> to specify Boehm GC's allocator. Does anyone have a hint ? Snippet code "main.cpp" follows, compiled with Boost Graph Library 1.32, Boehm GC 6.4 and G++ 3.3.5, with command line : $ g++ -o main main.cpp -lgc -lgccpp -- #include <boost/graph/adjacency_list.hpp> #include <gc/gc_allocator.h> #include <gc/gc_cpp.h> #include <iostream> #include <vector> #include <list> using namespace std; using namespace boost; namespace boost { struct collected_vecS {}; struct collected_listS {}; template <class ValueType> struct container_gen<collected_vecS, ValueType> { typedef vector<ValueType,gc_allocator<ValueType> > type; }; template <class ValueType> struct container_gen<collected_listS, ValueType> { typedef list<ValueType,gc_allocator<ValueType> > type; }; template <> struct parallel_edge_traits<collected_vecS> { typedef allow_parallel_edge_tag type; }; template <> struct parallel_edge_traits<collected_listS> { typedef allow_parallel_edge_tag type; }; namespace detail { template <> struct is_random_access<collected_vecS> { enum { value = true }; typedef true_type type; }; } } typedef adjacency_list<collected_vecS, collected_vecS, directedS, no_property, no_property, no_property, collected_listS> graph; int main() { // leaks... while(true){ graph * g=new (UseGC) graph; for(unsigned int i=0; i<100; ++i){ add_vertex(*g); } for(unsigned int i=0; i<100; ++i){ for(unsigned int j=0; j<100; ++j){ add_edge(i,j,*g); } } } }

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[statechart] history transitions make state-local-storage "un-cool"
by Mick Hollins 26 Jun '08

26 Jun '08

Apologies if this has been discussed before, but I couldn't find any mention of it: I am currently using the history facility of boost::fsm. I've discovered that when I re-enter a state, X, via a history transition I don't actually re-enter the same instance of X that I was in before, but instead enter a newly constructed instance of X. I just checked the UML spec regarding history transitions and it says that "Any necessary entry actions are performed", so given that boost::fsm uses constructors to represent entry actions I guess a new instance of X has to be constructed to ensure UML compliance. My actual concern is the effect this has on the "coolness" of state-local-storage (see http://boost-sandbox.sourceforge.net/libs/statechart/doc/faq.html#Whats_so_…) It seems to me that state-local-storage, which I agree is generally cool, is particularly un-cool (and bug-inducing) in the presence of history transitions. I'm not sure what a good alternative is, but just thought I'd raise the discussion. cheers, mick PS: does the history facility display the same semantics in boost::statechart? I plan to move to statechart real soon now ...

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regex lib for Windows Mobile
by Freeman Ng 07 May '08

07 May '08

I'm trying to get the regex library (Boost ver. 1.34.1) working under Visual Studio 7.0 and the Windows Mobile 6 SDK, and have run into the following problems: 1. Need to modify visualc.hpp to define BOOST_NO_STD_LOCALE and BOOST_NO_SWPRINTF. 2. WM6 runtime library doesn't have strxfrm() or wcsxfrm(). 3. regex lib makes direct calls to ansi versions of CreateFile(), LoadLibrary(), FindFirstFile(), and others (i.e. CreateFileA(), etc.) that don't exist on the WM platform. 4. w32_regex_traits.cpp has a pragma that links directly to a library that doesn't exist for WM. (user32.lib) #1 is normal and trivial, of course, but before I tackle #2 and #3 by either writing my own versions of the missing functions or modifying the regex source, and #4 by modifying the regex source (which I really hate to do, but I can't think of any other way around this one) I want to make sure I didn't miss anything. Is there some combination of #defines or project settings that should allow the library to build for VS 7 Windows Mobile? Am I about to do more work than I need to? Thanks. Freeman

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Re: [Boost-users] Applying Boost license to non boost projects
by Robert Marion 22 Apr '08

22 Apr '08

You may wish to consider applying the liberal BSD (http://www.opensource.org/licenses/bsd-license.php) or MIT (http://www.opensource.org/licenses/mit-license.php) licenses. These are both in widespread use for open source, and impose no restrictions, aside from attribution, on the user. Putting the license text at the top of all headers is not strictly necessary, but not a bad idea. Robert Marion http://www.palamida.com > I am interested in adopting the Boost Software license for an open source C++ > library (Castor: http://www.mpprogramming.com/2.html) > > [ snip ] > - Does this same guideline apply to non boost projects ? The need for stating > Boost.org there might confuse some users of non boost prj to think that the > library is supplied by Boost. > - Do all header files in my prj (which is a pure header library) need to > include this text at the top/somewhere in order to adopt the license. > > -Roshan

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Mac Xcode 3.0 Boost compile issue
by Daniel Lord 17 Apr '08

17 Apr '08

This is a specific error with Xcode 3.0 on Leopard not a generic Boost question: Something is screwy with the paths between Boost and Xcode: Xcode 3.0 needs to find the Boost includes, so I added my directory containing the top of the Boost tree (the boost_1_34_1 directory) to the User header Search paths in the build configuration for the target. No problem, everything appears to be found. However, adding that search path screws up something else: An error pops up in c++locale.h highlighting the line: const int __ret = std::snprintf(__out, __size, __fmt, __prec, __v); and claiming: "error: 'snprintf' is not a member of 'std'." What the freak? It compiles fine from the command line with g++ and using -I<same path to boost as above>. So it is some wierd interaction with Boost and Xcode paths but it make no sense to me. It's almost as if Boost is redefining something. But what? This does not occur if I don't add the Boost search paths but of course then the Boost definitions are not found. The program is a simple one from O'Reilly's C+++ Cookbook show below: #include <boost/filesystem/operations.hpp> #include <boost/filesystem/fstream.hpp> #include <iostream> using namespace boost::filesystem; int main(int argc, char** argv) { if (argc < 2) { std::cerr << "Usage: " << argv[0] << " [dir name]\n"; return(EXIT_FAILURE); } path fullPath = // Create the full, absolute path name system_complete(path(argv[1], native)); if (!exists(fullPath)) { std::cerr << "Error: the directory " << fullPath.string( ) << " does not exist.\n"; return(EXIT_FAILURE); } if (!is_directory(fullPath)) { std::cout << fullPath.string( ) << " is not a directory!\n"; return(EXIT_SUCCESS); } directory_iterator end; for (directory_iterator it(fullPath); it != end; ++it) { // Iterate through each // element in the dir, std::cout << it->leaf( ); // almost as you would if (is_directory(*it)) // an STL container std::cout << " (dir)"; std::cout << '\n'; } return(EXIT_SUCCESS); }

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Eclipse integration of bjam
by Ruediger Berlich 01 Apr '08

01 Apr '08

Dear all, I am using Eclipse/CDT under Linux as my standard IDE. So far I'm building my projects using Eclipse's own build mechanisms. Is anybody using bjam as a build mechanism in Eclipse/CDT and should I expect problems when making a switch to bjam ? Thanks and Best Regards, Ruediger

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boost serialization & module boundaries
by Christian Widmer 19 Mar '08

19 Mar '08

Hi, I'm trying to use boost to serialize a machine learning library that I'm working with. It all worked out very conveniently, but it seems now, that I have hit a dead end. I've been looking on the net but couldn't find any information that worked for me, so here we go: The problem is, that the library consists of several modules, which are dynamically linked. For instance the class KernelMachine has a field kernel of type Kernel, which is contained in a separate module (in the sense of a shared object). The following code compiles, but when I try to serialize a CKernelMachine object I get an "unregistered_class" error. (CKernel does serialize fine, when called directly) class CKernelMachine : public CClassifier { private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & boost::serialization::base_object<CClassifier>(*this); ar.register_type(static_cast<CGaussianKernel *>(NULL)); ar & kernel; std::cout << "done CKernelMachine" << std::endl; } protected: CKernel* kernel; }; I found some threads that pointed me towards BOOST_CLASS_EXPORT, but I'm not exactly sure how to use it. So my question is - is it in principle even possible to serialize across module (shared-object) boundaries. If so, how should I go about? Any pointers would be greatly appreciated. - Chris

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[serialization] Cannot increase version of stored objects
by Robert Bielik 15 Mar '08

15 Mar '08

I need to update the version certain objects in my structure, but I cannot get the version number incremented. Scenario: I have a class MyClass which have several entries of InternalClass objects (which is the one I want a new version of): class MyClass { ... template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION("MyInternals", m_vector_of_internal_class_objects); } std::vector<InternalClass> m_vector_of_internal_class_objects; class InternalClass { template<class Archive> void save(Archive & ar, const unsigned int version) const { ar & BOOST_SERIALIZATION("data", m_data); } template<class Archive> void load(Archive & ar, const unsigned int version) { if (version == 0) { old_data_t tmp; ar & BOOST_SERIALIZATION("data", tmp); m_data = convertToNewData(tmp); } else { BOOST_CHECK(version == 1); ar & BOOST_SERIALIZATION("data", m_data); } } BOOST_SERIALIZATION_SPLIT_MEMBER() new_data_t m_data; } } Then in the body (.cpp) I define: BOOST_CLASS_VERSION(MyClass::InternalClass, boost::serialization::object_class_info) BOOST_CLASS_VERSION(MyClass::InternalClass, 1) But when saving to the XML archive file, I still get version="0" for the InternalClass objects (?) /R

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[python] "Interpreter not initialized"
by Robert Dailey 13 Mar '08

13 Mar '08

Hi, When I execute the following code: BEGIN CODE -------------------------------------------------- #define BOOST_PYTHON_DEF( func ) boost::python::def( #func, func ) using namespace boost::python; static char const* PrintHelloWorld() { return "Hello World!"; } BOOST_PYTHON_MODULE(Script) { BOOST_PYTHON_DEF( PrintHelloWorld ); } void BeginPythonTest() { try { Py_Initialize(); initScript(); Py_Finalize(); } catch( error_already_set const& /*err*/ ) { PyErr_Print(); } catch( std::invalid_argument const& /*err*/ ) { PyErr_Print(); } } -------------------------------------------------- END CODE I receive the following error message: *Fatal Python error: Interpreter not initialized (version mismatch?)* This occurs when I step over the call to initScript() (in the code snippet above). I have no idea why this is happening. I'm currently linking against boost 1.34.1. I built all the libraries for boost myself using bjam. I built the multithreaded debug and release shared libraries. I'm using the SDK from Python 2.5.1. I also built the debug and release shared libraries for Python myself. My operating system is Microsoft Windows XP Professional. All help is appreciated. Thanks in advance!

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[mpl] integral constant overflow
by klaus triendl 11 Mar '08

11 Mar '08

Hi, I've recently started studying the book "c++ template meta programming" (I like it a lot!) and one of my own exercises was to get an integral type's max/min value. To get the type's maximal value I've created a metafunction max_val; Compiling the code below with vc++2008 warning level 2+ yields the warning "truncation of constant value" or "integral constant overflow" if I use an int instead of a char. <code> namespace mpl = boost::mpl; template<typename T> struct significant_bits: mpl::int_<std::numeric_limits<T>::digits> {}; template<typename T> struct max_val_impl: mpl::accumulate< mpl::range_c<int, 1, significant_bits<T>::value>, mpl::integral_c<T, 1>, mpl::next<mpl::plus<mpl::_1, mpl::_1> > > {}; template<typename T> struct max_val: max_val_impl<T>::type { BOOST_MPL_ASSERT((boost::is_integral<T>)); }; int main() { const char maxval = max_val<char>::value; return 0; } </code> The problematic metafunction instantiation boils down to mpl::integral_c<char, 127> where mpl::integral_c<char, 127>::next results in 128 which is then truncated. Of course I can turn off the compiler warnings but since the warning happens in integral_wrapper.hpp and the integral constant stuff is included in many other files including the boost type traits it would be tedious to always remember to include integral_c.hpp explicitly before any other headers with the warnings turned off. I don't know whether there is a really satisfying option, just wanted to discuss this point. Klaus Triendl

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[thread] Priority?
by Ovanes Markarian 10 Mar '08

10 Mar '08

Hello, I used boost thread library a lot and like it very much. Currently, I was reading the C++ Standerd proposal and saw that a thread (as well as boost::thread) does not have a priority. Which reason was it not to implement the thread priority in boost, and why is it not considered in the upcoming standard? I understand this feature is rarely required, but if someone suddenly needs to start a real-time priority thread he/she will be forced to use a third party lib again. Or is there smth. what I miss? Many thanks, Ovanes

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boost exceptions on MacOS 10.5
by Lothar May 09 Mar '08

09 Mar '08

Hi, I've brought this up before, but I still have no solution for this issue, so I will give it another try: Does anyone have boost 1.34.1 compiled on MacOS 10.5 where exceptions can be caught? You might use the following code to test: --cut here-- #include <iostream> #include <boost/filesystem.hpp> using namespace std; using namespace boost::filesystem; int main() { try { directory_iterator i("does_not_exist"); } catch(...) { cout << "This is never printed on MacOS 10.5." << endl; } return 0; } --cut here-- If this works with your installation of boost on MacOS 10.5, please tell me which steps you did to compile boost, and whether you used the static or dynamic version. A related question is: Is boost "supposed to work" on MacOS 10.5? Thanks, Lothar

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ASIO: ssl - load_verify_file
by j.c. 07 Mar '08

07 Mar '08

Hello, I have implemented a TLS client/server application and will be using self-assigned certificates due to the small scale of distribution. I am currently using the function load_verify_file("ca.pem"), however I don't want to write the certificate to end-users disk. What would be the proper way to use an "in-memory or compiled" certificate for peer verification? Thanks, JC

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[regex] Question about pattern
by office＠mgs.co.at 06 Mar '08

06 Mar '08

Hi; I'm a newbie to regex patterns and need help in a relative simple task: I use boost::regex with perl syntax and I have to parse user input that provides a feature similar to the conditional formatting of cells in OpenOffice Calc. The string the user enters looks like this: >=30 [fg:red] [bg:white] or <0.0 [fg:none] [bg:transparent] First the user can enter an optional operator (> < <> = <= >=) followed by a integer or floating point number. This whole term is optional so [fg:red] [bg:white] is also a valid expression. The terms for color selection are partly optional, so valid expressions are [fg:red] or [bg:white] or [fg:red][bg:white] or [bg:white][fg:red] The key words for foreground and background colors are predefined by the software (red, green, blue, transparent, none, ...). I tried starting with a pattern like (C++ syntax for strings) ^(?:(<|<=|>|>=|=|<>){1}((?:-|\\+)?[0-9]+(?:\\.[0-9]+|\\,[0-9]+)?))?(?:\\s*)(?:(\\[FG:(?:BLUE|RED|GREEN|BLACK|YELLOW|WHITE|CYAN|NONE)\\])|(\\[BG:(?:BLUE|RED|GREEN|BLACK|YELLOW|WHITE|CYAN)\\])|(\\[FG:(?:BBLUE|RED|GREEN|BLACK|YELLOW|WHITE|CYAN|NONE)\\])(?:\\s*)(\\[BG:(?:BLUE|RED|GREEN|BLACK|YELLOW|WHITE|CYAN)\\])){1}$ But this does not allow the [fg:][bg:] terms to be interchanged and also when a new color or style will be added to the format class I have to change the pattern three times. I tried backward references with no success. So any help is very welcome Thanks in advance Martin

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