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List host change
by Jon Kalb 04 Sep '03

04 Sep '03

Boost Users, We are moving the Boost-Users mailing list from Yahoo! Groups to a mailman based system. This means that effective immediately mail for Boost Users should be send to boost-users(a)lists.boost.org. You can manage your own subscriptions at http://lists.boost.org/mailman/listinfo.cgi/boost-users . If you have been subscribed to this list receiving individual mail messages or digest messages, then we have subscribed you to the mailman list with the same settings. If you were subscribed with either "no email" or "special emails only" then you will need to re-subscribe to the list by visiting http://lists.boost.org/mailman/listinfo.cgi/boost-users . Note that in order to send messages to this list you must be subscribed to the list. This does not mean that you must receive email from the list. You can use the "no email" setting and read and reply by newsgroup, but you must be a subscriber or your messages will not be accepted. If you have any questions or problems please contact the list moderators at boost-users-owner(a)lists.boost.org. Please note that questions and problems related to the list are off topic on this list and should only be sent to the list moderators. -- Jon Kalb SmartFriends(TM) U: Languages and Libraries Kalb(a)LibertySoft.com Sept. 26-28 http://SmartFriends.com/U Keynote: STL Creator, Alexander Stepanov

1 0

Pb with threads on Mac OS X Carbon.
by degaine1966 03 Sep '03

03 Sep '03

Hi, I'd like to use shared pointers with CodeWarrior 8.3 in a Carbon application. I have some preprocessing errors, the first one being relative to a thread Macro being undefined: lightweight_mutex.hpp line 86 # error Unrecognized threading platform I read in boot/config/plateform/macos.hpp that Boost was thread safe under Carbon but apparently there is no macro to define the usable type of thread... Any help appreciated, Bruno

1 0

Filesystem Lib Feature Request
by Robert W. Johnstone 03 Sep '03

03 Sep '03

Hello, Has any thought been given to member functions for the path class for handling filename extensions? It should be easy to add code for most systems to extract or change the extension. Thanks, ------------------------------------------ Robert Johnstone Simon Fraser University http://www.sfu.ca/~rjohnsto/

2 1

ostream_iterator and std::copy - better solutions?
by Jeff Flinn 03 Sep '03

03 Sep '03

Before rolling my own, does boost have a facility to stream out an iterator range without the dangling delimiter at the end? For example std::ostream& operator<<( std::ostream& s, const MyClass& aC ) { const std::string lDelim( "," ); std::vector<int> lInts; lInts.push_back(1); lInts.push_back(2); lInts.push_back(3); std::ostream_iterator<int> lItr( s, lDelim.c_str() ); std::copy( lInts.begin(), lInts.end(), lItr ); } yields: 1,2,3, I'm thinking something like the following usage would be nice: s << range_streamer( lInts.begin(), lInts.end(), "{", "," "}" ); yielding: {1,2,3} Any thoughts? -- Jeff Flinn Applied Dynamics, International

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RE: [Boost-Users] boost lambda examples
by Paul Grenyer 03 Sep '03

03 Sep '03

Hi Matt > > >for_each( v.begin(), v.end(), cout << *_1 << '\n' ); > > >I get the following errors: > That only makes sense with vector<int*>... as per the example, from > memory... > I think you meant vp.begin() etc. Yes, that's it! So what I actually wanted was: for_each( v.begin(), v.end(), cout << _1 << '\n' ); That'll teach me copy code from two different examples without applying my brain to it. Thanks, Matt! Regards Paul Paul Grenyer Email: pjgrenyer(a)iee.org Web: www.paulgrenyer.co.uk You cant buy time, but you can sell your soul and the closest thing to heaven is to Rock n' Roll.

1 0

boost lambda examples
by paulgrenyer 03 Sep '03

03 Sep '03

Hi MSVC 7.1, Windows 2000 I'm trying to get to grips with the boost lambda library. I've managed to get the first example to work: #include <boost/lambda/lambda.hpp> #include <iostream> #include <cstdlib> #include <list> #include <algorithm> int main() { using namespace std; using namespace boost::lambda; list<int> v(10); for_each(v.begin(), v.end(), _1 = 12 ); return EXIT_SUCCESS; } but when I add the following line (also from the docs): for_each( v.begin(), v.end(), cout << *_1 << '\n' ); I get the following errors: error C2039: 'reference' : is not a member of 'std::iterator_traits<int>' error C2146: syntax error : missing ';' before identifier 'type' error C2501: 'boost::lambda::detail::contentsof_type<A>::type' : missing storage-class or type specifiers error C2039: 'type' : is not a member of 'boost::lambda::detail::contentsof_type<A>' error C2146: syntax error : missing ';' before identifier 'type' I've tried including some the other Lambda headers but this didn't improve the situation. Regards Paul

2 1

RE: [Boost-Users] boost lambda examples
by Hurd, Matthew 03 Sep '03

03 Sep '03

>From: paulgrenyer [mailto:pjgrenyer@iee.org] >Subject: [Boost-Users] boost lambda examples >for_each( v.begin(), v.end(), cout << *_1 << '\n' ); >I get the following errors: That only makes sense with vector<int*>... as per the example, from memory... I think you meant vp.begin() etc. Cheers, Matt.

1 0

"invalid token pasting" macro bug
by James W. Walker 03 Sep '03

03 Sep '03

When I use Spirit with CodeWarrior 9 (just released), I get a bunch of warnings as shown below. The CodeWarrior release notes explain that "According to the language standard, the '##' token pasting operator can only generate other tokens. This warning indicates when a paste was found that did not result in a token. The code will still compile as it did previously, but it may be a useful hint if the compiler emits an error later on." Warning : invalid token pasting of 'BOOST_PP_LIST_FIRST_I' and '(' (included from: expanding macro 'BOOST_PP_LIST_FIRST' expanding macro 'BOOST_PP_LIST_FOR_EACH_I_M_D' expanding macro 'BOOST_PP_LIST_FOR_EACH_I_M' expanding macro 'BOOST_PP_FOR_1_C' expanding macro 'BOOST_PP_FOR_1' expanding macro 'BOOST_PP_LIST_FOR_EACH_I' type_traits.hpp:58 composite.ipp:16 composite.hpp:15 directives.hpp:27 numerics.hpp:19 core.hpp:34 spirit.hpp:30 ParseCalcLine.cp:5) type_with_alignment.hpp line 55 on_ptr, BOOST_PP_NIL)))))))))))) -- <http://www.jwwalker.com/>

4 3

how to create fixtures in unit test framework
by Anders Moe 03 Sep '03

03 Sep '03

Hi all. The boost unit test framework seems to lack the xUnit buildUp/tearDown (whatever) methods meant to faciliate the creation of fixtures. Does that mean there is an alternative idiom to achieve the same effect ? Constructing new class-test-cases for each test seems a bit overkill. Regards, Anders.

7 14

Lambda operator= question
by Rodolfo Lima 02 Sep '03

02 Sep '03

Hi people, That's the first time I'm using lambda and I'm stuck with something that can be resumed to: struct A { int Test() { return 0; } }; int x; A a; (var(x)=bind(&A::Test,_1))(a); In other words, I want to make a functor that calls a member function and stores its return value in some variable. I'm compiling with VC7.1 and it returns error C2440: '=' : cannot convert from 'const boost::tuples::cons<HT,TT>::stored_head_type' to 'int' Is there something I can do to get rid of this error and compile successfully? I'm appending the whole compiler output in the end of the post. Thanks, rod //--------- Whole compiler output c:\RodSoft\lib\boost\boost\lambda\detail\operator_lambda_func_base.hpp(242) : error C2440: '=' : cannot convert from 'const boost::tuples::cons<HT,TT>::stored_head_type' to 'int' with [ HT=const boost::lambda::detail::parameter_traits_<const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>>,const boost::lambda::detail::IF<false,const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>> &,const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>>>::RET>::type, TT=boost::tuples::detail::map_tuple_to_cons<boost::tuples::null_type,boost:: tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::t uples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tu ples::null_type,boost::tuples::null_type,boost::tuples::null_type>::type ] No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called c:\RodSoft\lib\boost\boost\lambda\detail\lambda_functors.hpp(153) : see reference to function template instantiation 'RET boost::lambda::lambda_functor_base<Act,Args>::call<boost::lambda::lambda_fun ctor_base<Act,Args>::sig<SigArgs>::type,A,const boost::tuples::null_type,const boost::tuples::null_type,const boost::tuples::null_type>(A &,B &,C &,Env &) const' being compiled with [ RET=boost::lambda::lambda_functor_base<boost::lambda::other_action<boost::la mbda::assignment_action>,boost::tuples::tuple<boost::lambda::lambda_functor< boost::lambda::identity<int &>>,const boost::lambda::detail::parameter_traits_<const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>>,const boost::lambda::detail::IF<false,const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>> &,const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>>>::RET>::type,boost::tuples::null_type,boost: :tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost:: tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::t uples::null_type>>::sig<boost::tuples::tuple<A &,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type ,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type, boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>> ::type, Act=boost::lambda::other_action<boost::lambda::assignment_action>, Args=boost::tuples::tuple<boost::lambda::lambda_functor<boost::lambda::ident ity<int &>>,const boost::lambda::detail::parameter_traits_<const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>>,const boost::lambda::detail::IF<false,const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>> &,const boost::_bi::bind_t<int,boost::_mfi::mf 0<int,A>,boost::_bi::list1<boost::_bi::list_av_1<boost::arg<1>>::B1>>>::RET> ::type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null _type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_ type,boost::tuples::null_type,boost::tuples::null_type>, SigArgs=boost::tuples::tuple<A &,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type ,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type, boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>, A=A, B=const boost::tuples::null_type, C=const boost::tuples::null_type, Env=const boost::tuples::null_type ] c:\RodSoft\pessoal\TstConsole\TstConsole.cpp(49) : see reference to function template instantiation 'boost::lambda::lambda_functor_base<Act,Args>::sig<SigArgs>::type boost::lambda::lambda_functor<T>::operator ()<A>(A &) const' being compiled with [ Act=boost::lambda::other_action<boost::lambda::assignment_action>, Args=boost::tuples::tuple<boost::lambda::lambda_functor<boost::lambda::ident ity<int &>>,const boost::lambda::detail::parameter_traits_<const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>>,const boost::lambda::detail::IF<false,const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>> &,const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>>>::RET>::type,boost::tuples::null_type,boost: :tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost:: tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::t uples::null_type>, SigArgs=boost::tuples::tuple<A &,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type ,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type, boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>, T=boost::lambda::lambda_functor_base<boost::lambda::other_action<boost::lamb da::assignment_action>,boost::tuples::tuple<boost::lambda::lambda_functor<bo ost::lambda::identity<int &>>,const boost::lambda::detail::parameter_traits_<const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>>,const boost::lambda::detail::IF<false,const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>> &,const boost::_bi::bind_t<int,boost::_mfi::mf0<int,A>,boost::_bi::list1<boost::_bi: :list_av_1<boost::arg<1>>::B1>>>::RET>::type,boost::tuples::null_type,boost: :tuples::null _type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_ type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_t ype>>, A=A ] Build log was saved at "file://c:\RodSoft\pessoal\TstConsole\Debug\BuildLog.htm" TstConsole - 1 error(s), 0 warning(s)

3 2

CodeWarrior PS2, Boost, & STL
by Yohann DOS SANTOS 02 Sep '03

02 Sep '03

Hello Boost Users, When i try to compile a class that use a vector with CodeWarrior for PS2 R3.03, i have this error message : Error : illegal use of incomplete struc/union/class 'Metrowerks::compile_assert<0>' (instantiating: 'std::vector<int, std::allocator<int>>') (instantiating: 'std::__vector_imp<int, std::allocator<int>, l>') vector line 729 ompile assert<bool(sizeof(T) == sizeof(typename Metrowerks::strore_as<T>;;type))> And just above the error line, in the vector file : // Error : illegal use of incomplete struct/union/class 'Metrowerks::compile_assert<0>' // This means that the store_as table in <msl_utility> is not set correctly. // sizeof(T) == sizeof(typename Metrowerks::store_as<T>::type must be true. The code compiles and works perfectly with VC6 sp5 on PC and XBOX. Thanks for any help.

2 1

[BGL] Adding one graph to another
by Tarjei Knapstad 02 Sep '03

02 Sep '03

I need to add/copy one graph into another, both completely connected, and then create an edge between one vertex in the original graph and a vertex in the one copied into it. The edge/vertex properties needs to be copied as well, and this needs to be fairly efficient. The new edge is straightforward, but is there any functionality for the copy/add operation? (Something like an "add_component" algorithm I guess...) To my understanding both the copy_graph and copy_component algorithms both replace all the content in the target graph. If not, what would be the most efficient way to solve this sort of problem? Cheers, -- Tarjei Knapstad

2 3

spirit list_p example
by Larry 02 Sep '03

02 Sep '03

From boost-1.30.2 I built the list_parser.cpp example using MSVC++7.1. In the CSV list I added ",,2" to the end of the line to be parsed. The program ran but the neither of the added elements were included in the output vector. Having used the tokenizer before I know it will generally gobble up adjacent delimiters without any output. You can get the empty token if you ask for the delimiters as well and then just discard the delimiters (sort of). But I was surprised that the 2 didn't make it to the output vector. I expected the empty list entry would not make the output vector. I tried adding ~anychar_p to the rule but that didn't help. If I change the input list to add ",\"\",2" I get "" and 2 in the output vector. Applications like spreadsheets do not put missing column values for numeric columns as "" items generally. Maybe I am missing something because it certainly isn't the behavior I would expect (either from the parser or the tokenizer).

4 9

adjancency propoerty iterator
by sashan 02 Sep '03

02 Sep '03

Hi Is there an adjancency iterator for property types. You can get an iterator for property types like this: typedef graph_property_iter_range<GraphType, vertex_name_t>::iterator VNameIterator; .... tie(It, ItEnd) = get_property_iter_range(m_Graph, vertex_name); I'd like to know if there is something similar for adjacency iterators. Thanks [Non-text portions of this message have been removed]

1 0

RE: [Boost-Users] Given std::map<ID,struct>, efficient way to access std::vector<struct.member>?
by Sam Partington 01 Sep '03

01 Sep '03

Well, I've trimmed you're example down some more, as to me it didn't seem to be important that the struct was a member of CFilter. So I think your question boils down to : struct A { int a; }; typedef std::map<int, A> my_map; void do_something_on_a_slice(int a) { // whatever } void f(const my_map& map_) { std::for_each(map_.begin(), map_.end(), /*what goes here*/); } You could use iterator_adaptors for this, but I think that is complicating things unnecessarily, something like this would work (untested) : struct select_a : std::unary_function<my_map::value_type, int> { const result_type& operator()(const argument_type& arg) const { return arg.second.a; } // similar non const operator here }; void f(const std::map<int, A>& map_) { boost::projection_iterator_generator<select_a, my_map::const_iterator>::type first(map_.begin()), last(map_.end()); std::for_each(first, last, do_something_on_a_slice); } See http://www.boost.org/libs/utility/projection_iterator.htm But I think bind in this situation is a better solution. (Partly because the interface to iterator_adaptors will be changing in the next release, possibly to the point of breaking the above code - Jeremy?) void f(const my_map& map_) { using boost::bind; std::for_each(map_.begin(), map_.end(), bind(do_something_on_a_slice, bind(&A::a, bind(&my_map::value_type::second, _1) ) ) ); } Though at this point I would consider writing a function object, any expression involving three bind's is getting close to (or some might say past) write-only code. As to efficiency, if this is a bottleneck it is mostly likely the iteration over the map that is causing the problem, or the actual 'doing' code. Most of the binding code should be optimised away by the compiler to a bare mimimum. It may be that you are better changing container, a sorted vector perhaps. HTH Sam (PS Apologies if I did miss a point somewhere and oversimplify your code) Chris Russell <> wrote: > Hello folks, I've got an interesting little design problem > and I'm looking > for some advice on how best to implement an efficient solution. (snip) > Here's a simplified statement of the problem that I believe > outlines the > relevant details: > > I've got a class declared as follows: > > --- begin example class ---- > In English: CFilter declares some structure with some number > of data members > of arbitrary types. Internally CFilter allocates a std::map of these > structures using some key_t. Effectively this defines a table > of data whose > rows are of type sRow_t, and whose columns can be conceptualized as > std::vector<A_t>, std::vector<B_t> where > std::vector<sRow_t.some_member>.size() == mapData<key_t, > sDataRow_t>.size(). > > At runtime, CFilter.ProcessRow is called std::map<key_t, > sRow_t>.size() times followed by a single call to CFilter.ProcessData. > > I'm trying to figure out how to _efficiently_ access the > column vectors in > the implementation of CFilter.ProcessData.

1 0

[BGL] Installing a property
by sashan 31 Aug '03

31 Aug '03

Hi I have a mass spring system where the particles are mapped to the vertex name property of the vertex. Now I've read (in the BGL red book) that one can install a custom property using an enumerated type. However it says that the enum must be a unique number. How do I enforce this in my code? Do I have to manually track the numbers myself? Thanks sashan [Non-text portions of this message have been removed]

2 1

Given std::map<ID,struct>, efficient way to access std::vector<struct.member>?
by Chris Russell 31 Aug '03

31 Aug '03

Hello folks, I've got an interesting little design problem and I'm looking for some advice on how best to implement an efficient solution. [ I posted this message to comp.lang.c++.moderated yesterday. I'm reposting here because this _seems_ like a job for some type of iterator adaptor and I'm thinking that perhaps one of the Boost libraries might be useful in this context. But which (if any)? Would uBLAS help me here perhaps? Or am I way off base? ] Here's a simplified statement of the problem that I believe outlines the relevant details: I've got a class declared as follows: --- begin example class ---- class CFilter { public: typedef struct tag_sRow { A_t A; B_t B; C_t C; .. .. .. // some number of structure members... } sRow_t; typedef std::map<key_t/*type unimportant*/, sDataRow_t> mapData_t; typedef mapDataSet_t::iterator mapiterData_t; typedef mapDataSet_t::const_iterator mapconstiterData_t; private: mapData_t m_mapData; public: void ProcessRow(const sRow_t& sRow) { // process a single row of data } // end method ProcessRow void ProcessData(const mapData_t& mapData) { // algorithm needs fast access to: // std::vector<A_t>, std::vector<B_t>, std::vector<C_t> .... } // end method ProcessData }; // end class declaration CFilter --- end example class --- In English: CFilter declares some structure with some number of data members of arbitrary types. Internally CFilter allocates a std::map of these structures using some key_t. Effectively this defines a table of data whose rows are of type sRow_t, and whose columns can be conceptualized as std::vector<A_t>, std::vector<B_t> where std::vector<sRow_t.some_member>.size() == mapData<key_t, sDataRow_t>.size(). At runtime, CFilter.ProcessRow is called std::map<key_t, sRow_t>.size() times followed by a single call to CFilter.ProcessData. I'm trying to figure out how to _efficiently_ access the column vectors in the implementation of CFilter.ProcessData. Any suggestions would be greatly appreciated. Thanks in advance - Chris Russell

1 0

Inconvenience in time_parsing.hpp - uninit variables
by Larry Knain 30 Aug '03

30 Aug '03

I was trying to use the date_time ptime functions with ISO syle input (boost 1.30.2 with MSVC++6 SP5). The function parse_undelimited_time_duration in time_parsing has three short variables hours, min, and sec that are uninitialized which lead to unpredictable results. These are at line 99. I stumbled on to this when I passed a string "20011027T0202" to ptime(from_iso_string()). To my surprise when I printed the value out it came back as 20011026T222345! The code works OK as is if you always pass a full HHMMSS. This must have been found in parse_delimited_time_duration as it has unsigned shorts that are intialized to zero.

2 1

[BGL] adjancency iterators for property types
by sashan 30 Aug '03

30 Aug '03

Hi Is there an adjancency iterator for property types. You can get an iterator for property types like this: typedef graph_property_iter_range<GraphType, vertex_name_t>::iterator VNameIterator; .... tie(It, ItEnd) = get_property_iter_range(m_Graph, vertex_name); I'd like to know if there is something similar for adjacency iterators. Thanks -- sashan http://www.cs.auckland.ac.nz/~sgov008/

1 0

boost::function syntax
by shyamemani 29 Aug '03

29 Aug '03

Hello everyone, I was looking at the boost::function preferable syntax. boost::funcion<float (int,int) > I also see that this has also been accepted by the standard for future STL implementation. The C++ grammar for template declaration is as stated below: template-argument-list: template-argument template-argument-list , template-argument template-argument: assignment-expression type-id id-expression None of the 'declaration' rules also seem to parse the tokens 'float (int,int) (I know I am missing something here). I could not figure out why the string 'float (int,int)' is accepted by the compiler and what type it is assigned? Is it just a extension of the standard by GCC? Can somebody help me figure this out? Thanks, Shyam

5 21

Broken link on boost.org/libs page
by Sam Partington 29 Aug '03

29 Aug '03

http://www.boost.org/libs/hdr_depend.html Is giving a HTTP 404 error. Cheers Sam

1 0

Re: Lambda shortcut?
by Daryle Walker 27 Aug '03

27 Aug '03

On Tuesday, August 26, 2003, at 10:05 AM, Jaakko Jarvi wrote: > In our last exciting episode Stephen Love wrote: >> operator-> *is* overloadable. > > It is, but not freely. The return type cannot be arbitrary, say a > lambda_functor type, making it not very useful for the LL. Specifically, the right side of "->" must be the NAME of a class' member or member function. It cannot be any kind of actual object (including pointers-to-member). This restricts the left side to: 1. A pointer to a (class/struct/union) data object (conventional C usage) 2. A class object with an "operator ->()" that returns a pointer to a data object 3. A class object with an "operator ->()" that returns an object that follows rules [2] or [3]. No matter what, "operator ->()" eventually leads to the standard C usage. All you can do is delay the event and build proxy objects to obtain the data. Daryle

1 0

Link errors
by Ken Crismon 26 Aug '03

26 Aug '03

To all, I am a new user to the BOOST community and am putting together some test code to get a handle on what BOOST is and how it works. Am using .NET 2003 and am getting the following link errors. error LNK2019: unresolved external symbol "__declspec(dllimport) public: class std::_Ptrit<char,int,char *,char &,char *,char &> __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::end(void)" Thanks in advance for the help, Ken Crismon

2 1

First Boost installation under Windows and Borland
by Matías Nicolás Bossa 26 Aug '03

26 Aug '03

Hello, I'm a new Boost user and I need to install it (v. 1.30.0) under Windows 2000, with Borland C++ Builder 6. I've succeed in correctly installing and using it under linux, but I couldn't install it under Windows. I downloaded and unpacked boost_1_30_0.zip. I set the following variables: BOOST_ROOT=d:\proyect\boost_1_30_0 TOOLS=borland BCCROOT=c:\archiv~1\borland\cbuilder6 PYTHON_ROOT=c:\win\python I compiled bjam.exe by running tools\build\jam_scr\build.bat, and put it somewhere in the path. (but I also tried downloading a precompiled version) I run bjam from the boost_1_30_0 directory and the following message appeared: /****************************************************/ /****************************************************/ ...found 5339 targets... ...updating 573 targets... borland-C++-action libs\python\build\bin\boost_python.dll\borland\debug\runtime-link-dynamic\numeric.obj libs\python\build\../src\numeric.cpp: Error E2401 D:\project\boost_1_30_0\boost/python/object/inheritance.hpp 69: Invalid template argument list Error E2040 D:\project\boost_1_30_0\boost/python/object/inheritance.hpp 69: Declaration terminated incorrectly Error E2231 D:\project\boost_1_30_0\boost/python/object/inheritance.hpp 130: Member cast_generator<Source,Target>::is_upcast cannot be used without an object Error E2401 D:\project\boost_1_30_0\boost/python/object/inheritance.hpp 131: Invalid template argument list Error E2040 D:\project\boost_1_30_0\boost/python/object/inheritance.hpp 132: Declaration terminated incorrectly Error E2228 D:\project\boost_1_30_0\boost/python/object/inheritance.hpp 132: Too many error or warning messages *** 6 errors in Compile *** /****************************************************/ /****************************************************/ For the moment I just need ublas and random libraries, I need boost in order to compile another library which use it, called Bayes++. I wil be very grateful if someone could help me, and I'm sorry for the length of the mail. Regards, Matías ___________________________________________________ Yahoo! Messenger - Nueva versión GRATIS Super Webcam, voz, caritas animadas, y más... http://messenger.yahoo.es

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Lambda shortcut?
by Hurd, Matthew 26 Aug '03

26 Aug '03

Hi, Is there a short cut for bind(&class::method_name, this, _1)? I could wrap it in a macro, as I use it enough, but is there something nicer I'm missing? I often just do the for loop as it is a little more readable, maybe... For example, for( some_collection::iterator i = check_list.begin(); i!= check_list.end(); ++i ) { turn_off_calcs(*i); } Is hopefully the same as for_each( check_list.begin(), check_list.end(), lambda::bind(&instrument_store::turn_off_calcs,this,lambda::_1) ); Regards, Matt.

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