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

Need Digest
by Daryle Walker 05 Dec '01

05 Dec '01

I guess Yahoo Groups had a data burp on 21 Nov 2001, because I didn't get digest 22. Could anyone send it to me? -- Daryle Walker Mac, Internet, and Video Game Junkie darylew AT mac DOT com

1 0

OT: Is there a forum for Loki anywhere on the 'net?
by Gooch, Allen 04 Dec '01

04 Dec '01

I know that pieces of Loki are being reviewed for inclusion into Boost, but I was wondering if there is any sort of forum for questions regarding the use of Loki itself, specifically Loki::SmartPtr. Please respond by email to avoid list clutter, unless it relates to boost use. TIA, Allen Gooch

2 1

Re: [Boost-Users] Re: Installing on Windows 95 with Mingw32 1.1
by John Maddock 02 Dec '01

02 Dec '01

>ISTR that when I tried to use boost.threads in the past on Win98, I >encountered problems with the TSS code as well - with MSVC. I didn't see the >page faults since a catch(...) handler on MSVC eats them but the results >were worse than that - the machine locked up in about half of the cases, in >the other half the thread that faulted died without warning. I haven't seen that. >I think that it's possible that the problem is not gcc-specific. Note that >both your successes use pthreads-win32, not the native win32 implementation >of Boost.Threads. the tests run fine using the win32 threads API as well (at least for me), the reason I used pthreads-win32 was to make the tests more directly comparable to cygwin (which has it's own pthreads API). - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

1 0

graph library compilation on VC++
by zhang3284＠yahoo.com 02 Dec '01

02 Dec '01

I'm new to BGL and studying the examples provided with the library. Here is a problem I'm having: I compiled a program, for example,dfs- example.cpp, it was fine. And then I changed the program a little bit, and tried to recompile it, I got the following error: boost\iterator_adaptors.hpp(845) : fatal error C1001: INTERNAL COMPILER ERROR Then I tried Rebuild All or cleaned the project first, and then compiled it. It became OK again. I'm using VC++ 6.0 SP5. Any comment would be appreciated. Thanks. Yingjun Zhang

2 1

operator<< for boost::any
by Patrick Guio 01 Dec '01

01 Dec '01

Dear all, I am trying to use the any class in a project. I would need to print elements of a vector<any>. I have come to the following solution as an example: template<class T> inline ostream& operator<<(ostream &os, const vector<T> &v) { vector<T>::const_iterator iter(v.begin()); for (int c(0), n(v.size()); c<n-1; c++) os << *iter++ << ','; return os << *iter; } typedef vector<bool> vectb; int main() { vector<any> values; double f(2.0); string s("hello"); int i(100); bool b(false); vectb vectbool; vectbool.push_back(true); vectbool.push_back(false); vectbool.push_back(true); vectbool.push_back(true); vectbool.push_back(false); vectbool.push_back(true); values.push_back(f); values.push_back(s); values.push_back(i); values.push_back(b); values.push_back(vectbool); for (vector<any>::iterator i(values.begin()), last(values.end()); i!=last; i++) { if (any_cast<bool>(i)) cout << *any_cast<bool>(i) << endl; else if (any_cast<int>(i)) cout << *any_cast<int>(i) << endl; else if (any_cast<float>(i)) cout << *any_cast<float>(i) << endl; else if (any_cast<double>(i)) cout << *any_cast<double>(i) << endl; else if (any_cast<string>(i)) cout << *any_cast<string>(i) << endl; else if (any_cast<vectb>(i)) cout << *any_cast<vectb>(i) << endl; } } But I would like a more general solution without to make assumptions about the type. Do you have any ideas? Another point is that I cannot figure out how to convert the solution below in terms of a friend ostream& operator<<(ostream &os, const any &rhs) I cannot get this compiled with g++ v 2.95 friend ostream& operator<<(ostream &os, const any &rhs) { return os << *any_cast<bool>(rhs); } Sincerely, Patrick ====================================================================== Patrick Guio Institute of Physics, University of Oslo P.O. box 1048, Blindern, N-0316 Oslo Tel : (+47) 22 84 40 60 - Fax : (+47) 22 85 56 71 E-mail : patrick.guio(a)fys.uio.no URL : http://folk.uio.no/~patricg

4 4

Re: Installing on Windows 95 with Mingw32 1.1
by John Maddock 01 Dec '01

01 Dec '01

>I got the command line gdb to run, but what a pain. I'm researching >both the GUI version as well as the JIT versions available for >mingw. They may help out. However, the command line version just >stranded me with no clear idea why things were failing, so I don't >know if the other debuggers will be much help. If it helps, I tried debugging the thread code with the latest cygwin GUI debugger (which is almost usable BTW), but still couldn't figure out what the issue was. I also tried with vc6+pthreads-win32 and Borland+pthreads-win32 and both of those check out OK, in the latter case I was able to build both boost.threads and pthreads-win32 with Borlands Codeguard support enabled, and there were no memory related errors, so I think this is something very specific to gcc. BTW I also see a page fault when building with gcc3.01 on Linux - this time the fault goes away if I build in release mode, so I suspect there is an assertion being triggered somewhere, and it's the assertion that's dying. I haven't got any further than that though. - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

3 3

Installing on Windows 95 with Mingw32 1.1
by karsjens+yahoo＠visionary.com 30 Nov '01

30 Nov '01

Since I had quite a bit of trouble getting started with boost, I though i would document my difficulties so the install process can be improved and other users having similar difficulties might benefit from my experience. I have placed my story on the boost wiki in the topic InstallingOnMingw32Windows95 Direct url: http://www.crystalclearsoftware.com/cgi-bin/boost_ wiki/wiki.pl?InstallingOnMingw32Windows95 I hope this is helpful to somebody. -- Brad Karsjens

3 4

regex and tokenizer, something wrong with namspace ?
by John Maddock 30 Nov '01

30 Nov '01

>I am a new user of the boost library (Actually with VC6 SP5 and stlport 4.0). Everything goes well when I use tokenizer and regexp in separated programs. But when I want to use the regex and the tokenizer library together I can not compile. for example, if I take the $(BOOST_ROOT)/libs/tokenizer/examples.cpp from John R. Bandela and just add the include line: #include <boost/regex.hpp> the compiler gives me this error: < regex and tokeniser appear to use different workarounds for the broken VC6 namespace support, and these seem to conflict, IMO regex is using the correct fix - or at least the one we discussed during the early days of boost, but then I would say that :-) - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

1 0

warning: unknown rule split
by John Merrells 29 Nov '01

29 Nov '01

I just downloaded boost and the jam.exe on the build page. Executing jam -ftools/build/allyoubase.jam -sTOOLS="msvc" on win2k with msvc 6 I get a screenful of 'warning: unknown rule split'. Anyone experienced this? jam version problem? John [Non-text portions of this message have been removed]

3 5

RE: [Boost-Users] graph library
by Jim.Hyslop 29 Nov '01

29 Nov '01

Ihsan Ali Al Darhi [SMTP:iad929@joinnet.com.jo] wrote: > Can someone of you point me to a good book or URL on graph theory? Ineed > this to understand the BGL. Please. I've found Robert Sedgewick's book "Algorithms in C++" to be quite useful. He has several chapters devoted to graph algorithms. He explains some of the basics, then demonstrates how to implement the algorithms. There are a lot of other algorithms covered as well (string processing, searching and sorting algorithms, geometric algorithms, and so on). -- Jim

1 0

problem compiling boost.function w/ g++ 2.95.3
by Darin Buck 29 Nov '01

29 Nov '01

when trying to compile the following code (cut from the boost.function test suite): #include <boost/bind.hpp> #include <boost/function.hpp> #include <iostream> #include <string> #include <functional> struct X { X(int v) : value(v) {} int twice() const { return 2*value; } int plus(int v) { return value + v; } int value; }; int main() { using namespace boost; boost::function<int, X*> f1(&X::twice); X one(1); cout << "f1(one) = " << f1(&one) << endl; return 0; } _____________________________________________ i get the following errors: /usr/local/include/boost/function/function_template.hpp: In function `static int boost::detail::function::function_obj_invoker1<int (X::*) () const,int,X *>::invoke(boost::detail::function::any_pointer, X *)': /usr/local/include/boost/function/function_template.hpp:689: instantiated from `boost::function1<int,X *,boost::empty_function_policy,boost::empty_function_mixin,allocator >::assign_to<int (X::*)() const>(int (X::* &)() const, boost::detail::function::function_obj_tag)' /usr/local/include/boost/function/function_template.hpp:618: instantiated from `boost::function1<int,X *,boost::empty_function_policy,boost::empty_function_mixin,allocator >::assign_to<int (X::*)() const>(int (X::* &)() const)' /usr/local/include/boost/function/function_template.hpp:463: instantiated from `boost::function1<int,X *,boost::empty_function_policy,boost::empty_function_mixin,allocator >::function1<int (X::*)() const>(int (X::* &)() const)' /usr/local/include/boost/function.hpp:459: instantiated from `boost::function<int,X *,boost::detail::function::unusable,boost::detail::function::unusable, boost::detail::function::unusable,boost::detail::function::unusable,bo ost::detail::function::unusable,boost::detail::function::unusable,boos t::detail::function::unusable,boost::detail::function::unusable,boost: :detail::function::unusable>::function<int (X::*)() const>(int (X::* &)() const)' hello.C:21: instantiated from here /usr/local/include/boost/function/function_template.hpp:272: pointer to member function called, but not in class scope /usr/local/include/boost/function/function_template.hpp:272: warning: control reaches end of non-void function `boost::detail::function::function_obj_invoker1<int (X::*)() const,int,X *>::invoke(boost::detail::function::any_pointer, X *)' /usr/local/include/g++-3/stl_alloc.h: At top level: /usr/local/include/g++-3/stl_alloc.h: In instantiation of `allocator<int (X::*)() const>': /usr/local/include/boost/function/function_base.hpp:131: instantiated from `boost::detail::function::functor_manager<int (X::*) () const,allocator<boost::function_base> >' /usr/local/include/boost/function/function_template.hpp:691: instantiated from `boost::function1<int,X *,boost::empty_function_policy,boost::empty_function_mixin,allocator >::assign_to<int (X::*)() const>(int (X::* &)() const, boost::detail::function::function_obj_tag)' /usr/local/include/boost/function/function_template.hpp:618: instantiated from `boost::function1<int,X *,boost::empty_function_policy,boost::empty_function_mixin,allocator >::assign_to<int (X::*)() const>(int (X::* &)() const)' /usr/local/include/boost/function/function_template.hpp:463: instantiated from `boost::function1<int,X *,boost::empty_function_policy,boost::empty_function_mixin,allocator >::function1<int (X::*)() const>(int (X::* &)() const)' /usr/local/include/boost/function.hpp:459: instantiated from `boost::function<int,X *,boost::detail::function::unusable,boost::detail::function::unusable, boost::detail::function::unusable,boost::detail::function::unusable,bo ost::detail::function::unusable,boost::detail::function::unusable,boos t::detail::function::unusable,boost::detail::function::unusable,boost: :detail::function::unusable>::function<int (X::*)() const>(int (X::* &)() const)' hello.C:21: instantiated from here /usr/local/include/g++-3/stl_alloc.h:750: `allocator<int (X::*)() const>::address(int (X::* &)() const) const' has already been declared in `allocator<int (X::*)() const>' make: *** [hello.o] Error 1 ___________________________________ this code should compile (its just copied from the test code) and my compiler setup should work according to the boost compiler status page. Any ideas what i'm doing wrong? -Darin Buck

2 2

regex and tokenizer, something wrong with namspace ?
by acarsac＠yahoo.fr 28 Nov '01

28 Nov '01

Hi, I am a new user of the boost library (Actually with VC6 SP5 and stlport 4.0). Everything goes well when I use tokenizer and regexp in separated programs. But when I want to use the regex and the tokenizer library together I can not compile. for example, if I take the $(BOOST_ROOT)/libs/tokenizer/examples.cpp from John R. Bandela and just add the include line: #include <boost/regex.hpp> the compiler gives me this error: Compiling... examples.cpp c:\program files\microsoft visual studio\vc98 \include\boost\token_functions.hpp(264) : error C2668: 'ispunct' : ambiguous call to overloaded function c:\program files\microsoft visual studio\vc98 \include\boost\token_functions.hpp(257) : while compiling class- template member function 'bool __thiscall boost::char_delimiters_separator<char,class _STL::char_traits<char> >::is_ret(char) const' Error executing cl.exe. examples.exe - 1 error(s), 0 warning(s) any idees ? Alexandre

3 7

Typelists.
by jamescurran＠mvps.org 28 Nov '01

28 Nov '01

Over on the Boost Developer group, there a lot of talk about how to best implement a typelist. Just so I can follow that discussion, could someone give me the basic thumbnail sketch of what exactly a typelist is, and what they are used for?

3 2

Real-world applications using Boost - results
by Björn Karlsson 27 Nov '01

27 Nov '01

I recently posted a question about "real-world" use of Boost. The (surprisingly few) answers I received can be found at the end of the e-mail. I think it is safe to say that the usage is more widely spread than the answers indicate. [Note: I have excluded the names from the e-mails, although not explicitly asked to do so.] Summary: There were replies from 8 Boosters. It seems that the lightweight utility classes are the most popular, likely due to the fact that their impact on existing systems is easily manageable. Thank you for your answers! Bjorn Karlsson Reply ////////////////////////////////////////////////////////////////////////// Using some small parts of it. Selected because it lets you pick and chose things to use from a large set of (relatively) small components/tools rather than ending up "buying into" some grand scheme of things. Well designed small interfaces rather than including the kitchen sink, making it easier for people to pick up/maintain code later.... Did what I needed to do at the time.... Note that the things I have elected to use so far have been small and intended to reduce the risk of mistakes (eg operators, traits) rather than anything vast. Reply [translated] ////////////////////////////////////////////////////////////////////////// We have just started to use Boost for converting a Python prototype to C++. The experience is still limited, but the results after a few days of work are very good. Reply ////////////////////////////////////////////////////////////////////////// I'm using Boost heavily in FEMTown (www.femtown.org) FEMTown is an open-source finite-element framework in development. We're using Boost because it provides stable and slim functionality that helps us making FEMTown more efficient, flexible and robust. (although our choice of C++ for a scientific application is even kinda controversial) Reply ////////////////////////////////////////////////////////////////////////// At this moment, I'm using the Boost lexical_cast in one of our commercial software products (Pilot - see http://www.leitch.com/custserv/products.nsf/lookup/CCS-PILOT) I needed to convert from integers to text for transmission across the network, then back from text to integer value. I had been using strstream, but the lexical_cast wrapped all the complexity up for me. I chose Boost because it's portable (our software runs on Windows NT and on embedded software using gcc). I knew there is a good chance that lexical_cast will become a standard keyword. As I learn more about the various libraries that are available, I will likely find appropriate places to use them. Reply ////////////////////////////////////////////////////////////////////////// My group is currently using Boost on one project as an experiment. We do cross-platform Macintosh/Windows development and it was valuable to have a tested library that worked on our two main development platforms. We have been phasing different parts of Boost in as come across problems that Boost will solve. As a community I find Boost a source of best practices that I have tried to implement in our workplace. Reply ////////////////////////////////////////////////////////////////////////// We've been using Boost at Zetec for over two years. Initially just for shared_ptr, but since expanding to lexical_cast, iterator_adaptors, tokenizer, and others. If you need any other info, let me know. Reply ////////////////////////////////////////////////////////////////////////// I am starting a new project using boost. It is a financial risk-management engine. I cannot tell you a lot about it yet. We are a team of 8 developers, 4 developing the backend and 4 developing the interfaces. The product will hopefully be a big success in the financial world as it is developed in cooperation with some the best people of the financial industry. It is a 12 months development effort using the XP development process. boost will be used to provide some utility classes (smart pointers, anys, threads ... ). The engine will run on Solaris and Linux. A future version on Windows may exist in the future. Reply ////////////////////////////////////////////////////////////////////////// We've used small parts of Boost in a digital video distribution back-end system; the system was developed by a client of us(us=CMG). If you want names in your summary I'd have to ask for permissions from them.

1 0

(no subject)
by Paul Grenyer 25 Nov '01

25 Nov '01

Paul Grenyer pjgrenyer(a)iee.org

1 0

"referenced symbol not found" when loading modules
by dlrubin＠yahoo.com 25 Nov '01

25 Nov '01

I'm getting a "refernced symbol not found" error when loading modules compiled with Boost. I tried using boost using this example code: #include <stdio.h> #include <string> #include <boost/python/class_builder.hpp> namespace { std::string greet() { return "hello, world"; } int square(int number) { return number * number; } } namespace python = boost::python; BOOST_PYTHON_MODULE_INIT(example) { try { // Create an object representing this extension module. python::module_builder this_module("example"); // Add regular functions to the module. this_module.def(greet, "greet"); } catch(...) { python::handle_exception(); // Deal with the exception for Python } } and when I try importing into python, here's the error I get: Python 2.1.1 (#5, Nov 22 2001, 14:04:45) [GCC 2.95.2 19991024 (release)] on sunos5 Type "copyright", "credits" or "license" for more information. >>> import example Traceback (most recent call last): File "<stdin>", line 1, in ? ImportError: ld.so.1: python: fatal: relocation error: file ./example.so: symbol handle_exception__Q25boost6pythonv: referenced symbol not found Any suggestions? thanks, Daniel

1 0

Introducing Me
by Paul Grenyer 24 Nov '01

24 Nov '01

Dear All I don't know if this is the appropriate thing to do here (I'm sure the moderator will filter me out if it isn't), but I failed to introduce myself on other lists and with hindsight I think it would have been better if I had. I've been programming in C++ for about 18 months, since I left university and started working. I was introduced to the C++ standard library and boost libraries a few months ago by a member of the ACCU. I have just started a new job writing distributed software using the C++ standard library and the ATL and I'm making as much use of boost as possible. Previous to that I was writing windows software to control dot markers and laser markers using the MFC. So, I am very new to boost and am not expecting to be able to contribute much for a while and I'll no doubt need the odd nudge in the right direct. Thanks Paul Paul Grenyer pjgrenyer(a)iee.org

1 0

Re: [boost] how to get a *real* copy of a boost-python object that supports virtual function
by Phil Austin 24 Nov '01

24 Nov '01

(I'm posting to both boost and boost-users, but I'm assuming we're supposed to move this kind of discussion to Boost-Users(a)yahoogroups.com?) dkottowk(a)yahoo.com writes: [snip] > my question is, how do i get a copy of PyGenome_Callback, > which also is a copy of the python-side of the object ? I'd also be interested in a pointer to an elegant way to do this, as well as an example of a from_python function that converts PyObject* to PyGenome_Callback. Brute force does work for me -- i.e. if you need the derived class and can't construct the object in Python code, you can call the derived constructor from the C++ side like this: PyObject* theMod=PyImport_ImportModule("mymodule"); PyObject* theDict=PyModule_GetDict(theMod); py::ref theRef(theDict); py::dictionary modDict(theRef); py::ref constructor=bDict.get_item(py::string("theObject").reference()); PyObject* theInstance=PyObject_CallObject(constructor.get(),0); This was ugly enough so that I added a python wrapper around my extension to construct the derived objects I needed in Python and pass them back to C++. Phil

1 0

boost tokenizer
by pjgrenyer＠iee.org 23 Nov '01

23 Nov '01

Dear All I'm using the boost tokenizer to tokenise lines similar to this one: first_initial |23|1| This gives me: first initial 23 1 but what I actually want is: first_initial 23 1 Does anyone know how to get it to ignore the underscore? Thanks Paul

3 2

passing data to a thread
by d33pmind＠yahoo.fr 23 Nov '01

23 Nov '01

How can I pass data to a thread ? Why does the boost::thread's constructor takes a boost::function0<void> as parameter, instead of a boost::function1<void> which would have allowed to pass it a pointer to a thread safe structure ? Julien.

2 1

core dump when invoking jam
by d33pmind＠yahoo.fr 23 Nov '01

23 Nov '01

On a Linux Mandrake 8.1 (i586), I succesfully built jam, but when I invoke it I got no output except a core dump. Has anyone encountered the same problem ? I compiled it with gcc 3.0.1, and modified gcc-tools.jam to use gcc- 3.0.1 and g++-3.0.1 instead of gcc and g++ (which are 2.96). Thanks. Julien.

2 1

What's safe_bool?
by mr_lilirong＠yahoo.com 23 Nov '01

23 Nov '01

Hi, The following code is excerpted from Boost.Function. I just don't unstanding it. Why use "safe_bool"? What's the advantage? Can any one explain it to me? Thanks. // code from <boost/function/function_base.hpp> // ===> private: struct dummy { void nonnull() {}; }; typedef void (dummy::*safe_bool)(); public: operator safe_bool () const { return (this->empty())? 0 : &dummy::nonnull; } safe_bool operator!() const { return (this->empty())? &dummy::nonnull : 0; } // code from <boost/function/function_base.hpp> // <===

2 2

aCC compilator
by lokys1976＠yahoo.com 22 Nov '01

22 Nov '01

Is it possible using aCC A.03.27 to use boost libraries? When I try to compile using boost examples, it dosn't understand "using namespece std" and so on, when I try to use aCC -AA than it can not find some libraries. Any suggestions how must I use aCC with boost libraries is welcomed very much thank you Paulius

2 1

Threads on MSVC 6.0
by brian_todoroff＠yahoo.com 22 Nov '01

22 Nov '01

I've been trying for a few hours now to get the threads lib examples to compile. I built the libraries with jam and all but python built correctly. When I create a new Win32 console application and copy the code ( See end of message from the thread class example and attempt to compile I get: ===================Start Error --------------------Configuration: threadtest - Win32 Debug----------- --------- Compiling... threadtest.cpp c:\projects\boost\threadtest\threadtest.cpp(27) : error C2228: left of '.join' must have class/struct/union type Error executing cl.exe. Creating browse info file... threadtest.exe - 1 error(s), 0 warning(s) ===================End Error Can't figure out what I'm doing wrong. Thanks for any help. Brian Todoroff ========================Start Code (to end) #include <boost/thread/xtime.hpp> #include <boost/thread/thread.hpp> #include <iostream> struct thread_alarm { thread_alarm(int secs) : m_secs(secs) { } void operator()() { boost::xtime xt; boost::xtime_get(&xt, boost::TIME_UTC); xt.sec += m_secs; boost::thread::sleep(xt); std::cout << "alarm sounded..." << std::endl; } int m_secs; }; int main(int argc, char* argv[]) { int secs = 5; std::cout << "setting alarm for 5 seconds..." << std::endl; boost::thread thrd(thread_alarm(secs)); thrd.join(); // Line 27 - Error here return 0; }

2 1

breadth_first_searchable graph, without invalidable vertex descriptors
by cristipp＠ics.uci.edu 21 Nov '01

21 Nov '01

Hello, I am trying to use the BCG as backbone for a ControlFlowGraph in a compiler project. It seems that I cannot use BCG for this task because of the follow contradicting (from BCG point of view) requirements: 1. I want to be able to breadth_first_search through my graph. 2. I want to be able to keep descriptors to vertices 'for ever' so I can refer a specific vertex at any given time (for removal or whatever other reasons). To implement requirement 1 my adjacency_list should have its VertexList of type vecS. To implement requirement 2 my adjacency_list should have its VertexList of type listS. Unfortunately those are mutualy exclusive and it seems that BCG is unsuited for the job. But I can't really think of a decent generic graph library unable to support those requirements. After all, it's all about being able to use basic graph traversals on randomly mutating graphs. STL has the list which has those nice properties, why a graph library should be different?! Perhaps I am missing something and I am asking for help: how should I declare my graph and how can I do a bfs on it? Thanks in advance, Cristi

2 5