- Boost-users - lists.boost.org

header-only libraries
by ilya shlyakhter 26 Mar '13

26 Mar '13

Dear Boost experts, I'd like to use the program_options library, but am reluctant to require my users to build parts of Boost. Is there a strong reason that this library cannot be header-only? Or perhaps, it's possible to create a header-only version of this library? I have the same question for regex. Thanks, ilya

3 2

[MSM] "favor_compile_time" policy disables "kleene" events. (Bug?)
by Deniz Bahadir 25 Mar '13

25 Mar '13

Hi everyone, Hi Christophe, While trying to speedup compilation of my MSM/eUML-based state machine, I seem to have found a bug. I added the "favor_compile_time" policy to the type-definition of my state-machine as the documentation suggests. I did not use the macro "BOOST_MSM_BACK_GENERATE_PROCESS_EVENT" because I do not have any sub-statemachines. This did speed up compilation, however obviously by changing my transition-table: All "kleene"-events in my transition-table are ignored, when defining the state-machine with the "favor_compile_time" policy. Can anyone confirm this or am I using it wrong? (Was this policy supposed to work with eUML in the first place?) Thanks, Deniz PS: I am using GCC 4.7.2 with Boost 1.53.

3 6

Broken Links?
by Hei Chan 25 Mar '13

25 Mar '13

Hi, On http://www.boost.org/doc/libs/1_53_0/libs/pool/doc/html/boost_pool/pool/poo…, all the graphs there seem broken. Anyone fixing it? Thanks in advance. Cheers, Hei

2 1

[boost::Statechart] posting a "serial timeout" event
by Andre de Jong 25 Mar '13

25 Mar '13

I've been using boost's asynchronous statechart to write a program. In this program I communicate with another device using an asynchronous serial port. I have a state that waits for a confirmation from the device over the serial port and then posts a "confirmation received" event. This works well but, I would also like to implement a "timeout" event. In previous programs I had been using switch case statements for my state machines where I had code that could be run each time the loop was run. This meant I could run code and check if I should change state due to something timing out. Like this: while(1){ switch (state){ case 0:{ sendMessage(); state = 1; sendTime = boost::chrono::steady_clock::now(); } break; case 1:{ if (isConfirmationReceived()){ // do something state = 2; } else if (boost::chrono::steady_clock::now() > start + boost::chrono::duration<double>(WAIT_LENGTH)){ //do something state = 3; } } break; // etc etc } } How would I implement something like this using boost::StateChart? Or, should i be thinking about this a completely different way?

1 0

Re: [Boost-users] Broken Links?
by Boost_mailinglist＠gmx.de 25 Mar '13

25 Mar '13

Hello, you can see the directory listing of the pictures under http://www.boost.org/doc/libs/1_53_0/libs/pool/doc/images/ -----Ursprüngliche Nachricht----- Gesendet: Montag, 25 März 2013 um 06:32:27 Uhr Von: "Hei Chan" <structurechart(a)yahoo.com> An: "boost-users(a)lists.boost.org" <boost-users(a)lists.boost.org> Betreff: [Boost-users] Broken Links? Hi, On�http://www.boost.org/doc/libs/1_53_0/libs/pool/doc/html/boost_pool/pool/…, all the graphs there seem broken. Anyone fixing it? Thanks in advance. Cheers, Hei _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

1 0

bad reloc address when compiling with mingw
by Leonardo Sá 24 Mar '13

24 Mar '13

Hi all, I have been trying to create an .exe that links to several boost libraries (date-time, python, etc.) using MinGW, cross compiling for windows on linux. I compiled boost using mingw without problems. When linking the exe, I am receiving the following error: CMakeFiles/fp_core_test.dir/objects.a(MockEnvironment.cpp.obj):MockEnvironment.cpp:(.text+0x381): undefined reference to `fp_core::Window::init(int, int, boost::shared_ptr<fp_core::Renderer>)' /usr/bin/i686-w64-mingw32-ld: CMakeFiles/fp_core_test.dir/objects.a(MockEnvironment.cpp.obj): bad reloc address 0x8 in section `.text$_ZN5boost6detail15sp_counted_baseC2Ev[boost::detail::sp_counted_base::sp_counted_base()] I have no idea what "bad reloc address" means. Googling wasn't much help. Anyone can give me a pointer in the right direction? Thanks!

1 0

newbie problem with Program Option string value
by Neil Sutton 24 Mar '13

24 Mar '13

I am having problems getting a program option to work. The option should enable a user to enter a location when they select the '--location' option. so, if you type --location canada, the code should store the supplied string - canada and pass it on to the program. This is a typical program option with nothing special. But I cannot seem to get it to work! Please look at this: ---------------------------------------------------- std::string place_option; // a global variable po::options_description general("General options"); general.add_options() ("location", po::value<std::string>(), "location of your home"); // there are other non string options po::variables_map vm; po::store(po::parse_command_line(ac,av, general),vm); po::notify(vm); if(vm.count("help")) { std::cout << general << "\n"; return 0; } if(vm.count("version, v")) { std::cout << "version aplha\n"; } if(vm.count("location")) { place_option = vm["location"].as<std::string>(); // should pass the string value entered at command line to std::string place. } If i run my program with eg 'myprogram --location disney' I get: terminate called after throwing an instance of 'std::logic_error' what(): basic_string::_S_construct NULL not valid Aborted ------------------------------ Now I have tried a few variations of the code. The examples show where an int value is supplied and retrieved. I cannot work out how to do - what should be very trivial. I simply want to recover the value associated with 'location' i.e a std::string entered at the command line. I then want to pass that value on to my program to do something with it. I do not understand the error. Can someone kindly show me the correct syntax to accomplish this please? Kind regards.

3 2

[iostreams] mapped_file path issue
by Alexandre 24 Mar '13

24 Mar '13

Hello, After reading through all the documentation and examples I could read, I still can't get the following piece of code to work . I assume that when you pass a new_file_size and a path to the mapped_file_params class , it will then open the file at the location desired when I call the constructor of mapped_file with the mapped_file_params object in parameter. But the only thing it does is to create a file with a weird name , like "%F8/134" in the project working directory, not where I told it to. Maybe I'm wrong and one should create file before specifying it to the mapped_file? After reading the doc, I was under the assumption that it created a new file when you fill in the new_file_size param. and specifies the filename. Anyone experienced this before? Any advice on how to resolve this? Here's the code: boost::iostreams::mapped_file_params param(filename); // filename is a std::string with the correct path param.flags = boost::iostreams::mapped_file::mapmode::readwrite; param.new_file_size = sizeNeeded; // sizeNeeded is the size of the data param.length = sizeNeeded; boost::iostreams::mapped_file fileMap(param); // at this point the file is created … Thanks for your time, Alexandre

1 0

[BGL] boost::disjoint_set getting new representative after link()
by Adi Shavit 23 Mar '13

23 Mar '13

Hi, I'm using boost::disjoint_sets_with_storage<>. After calling link(rep1, rep2), I want to know the new rep - the representative of the merged set. Obviously, I can call find_set(rep1) to find it. I assume that the extra call to find_set incurs an additional run-time cost per call to link. Is this true or is the call immediate (as in returning the immediate parent of rep1)? If it does incur a run-time cost, then we know that the new-rep is *either *rep1 or rep2. Is there some other way to know which one it is? On a related matter, I am also tracking the *size *of the sets for each link(). Does knowing the size of the rep set before the link help in determining which of rep1 or rep2 will be the new rep? Is there a simple way to extend boost::disjoint_sets_with_storage<> to do the size tracking internally (currenlty I keep an external size vector per rep to keep track of the link()s). Thanks, Adi

2 2

erase and put methods in property tree lib of boost
by Sashidhar Guntury 23 Mar '13

23 Mar '13

I have been trying to use the put and erase methods in boost's property tree library with very limited success. I have tried to go through the documentation but it seems really esoteric with no real example to demonstrate. This is what I would like to do - I have a json object. I look for a particular key (call it "title") and extract the corresponding value (call it "Eric Clapton"), do something with "Eric Clapton" (say change it to "ec") insert it in the place of the old value. Now, should I do an "erase" to remove the previous entry and then "put" the new pair? Will "put" replace the old value? void doSomething(const ptree& node) { ... BOOST_FOREACH(const ptree::value_type& child, node.get_child("artists")) { string text = child.second.get<string>("title"); // do something to the text to give text2 child.second.put("title", text2); } ... } The above code gives an error which is equally hard to understand. I was hoping someone would shed some light. thanks Sashidhar

2 2