Hello! What are the advantages of using boost.any library ? Could you please give me some real life examples ? Why the same functionality couldn't be achieved by having some generic type in the root of object's hierarchy and creating containers with that base type ? ...
The problem is pretty basic. (I am puzzled why the search didn't find anything) I have a rectangular "picture" that stores it's pixel color line after line in a std::vector I want to copy a rectangular region out of that picture. How would I elegantly code this in c++? My first try: template <class T> std::vector<T> copyRectFr...
Hi, I need to share a stack of strings between processes (possibly more complex objects in the future). I've decided to use boost::interprocess but I can't get it to work. I'm sure it's because I'm not understanding something. I followed their example, but I would really appreciate it if someone with experience with using that library...
Hi all, I use boost.test library to write unit tests for my application. The problem is, when one particular *.cpp file containing test suite grows up to certain size, compilation of that file becomes extremely slow. I use BOOST_AUTO_TEST_CASE macro to define test cases. Boost version is 1.34.1 Build env is autotools + gcc 4.3 under...
I'm thinking about serializing data in an application which is Qt-based. Essentially what I'm going to serialize is my hierarchical model, which is composed of different classes that derive from, say, TreeModelItem: class TreeModelItem { protected: QList<TreeModelItem *> m_children; //... }; Should I study boost::serialization an...
Hi I`m writing a web spider and want to use boost regex library instead of crafting some complicated parsing functions. I took a look at this example: #include <string> #include <map> #include <boost/regex.hpp> // purpose: // takes the contents of a file in the form of a string // and searches for all the C++ class definitions, ...
I'm trying to figure out how to wrap a boost::function member (used as an event callback) of an unmanaged class with a C++/CLI class event. I do not have control over the unmanaged class. All I can do is figure out how to write the C++/CLI class properly. Here's the example unmanaged class: class X { public: boost::function<void ...
What do you think? Is this correct or are there memory leaks? Source: #include <QList.h> #include <boost/shared_ptr.hpp> #include <iostream> class A { private: int m_data; public: A(int value=0) { m_data = value; } ~A() { std::cout << "destroying A(" << m_data << ")" << std::endl; } operator int() const { return m_data...
I am passed an Iterator and I have to pass it on to another function -- but filtered so that certain elements are skipped (it's a range of pointers, and I want to filter out the NULL pointers). I googled for "stl filter iterator" to see how to do this, and boost::filter_iterator came up. That looks nice and I could use it, but could ...
I'm new to C++ and am writing a multi-threaded app whereby different writers will be pushing objects onto a stack and readers pulling them off the stack (or at least pushing the pointer to an object).. Are there any structures built-into C++ which can handle this without adding locking code etc.? If not, what about the Boost libraries? ...
Hi I'm trying to write a regular expression for my html parser. I want to match a html tag with given attribute (eg. <div> with class="tab news selected" ) that contains one or more <a href> tags. The regexp should match the entire tag (from <div> to </div>). I always seem to get "memory exhausted" errors - my program probably takes ev...
I'd like to iterate over a std::map using BOOST_FOREACH and edit the values. I can't quite get it. typedef std::pair<int, int> IdSizePair_t; std::map<int,int> mmap; mmap[1] = 1; mmap[2] = 2; mmap[3] = 3; BOOST_FOREACH( IdSizePair_t i, mmap ) i.second++; // mmap should contain {2,3,4} here Of course this doesn't change anything...
The following code of mine compute the confidence interval using Chi-square's 'quantile' and probability function from Boost. I am trying to implement this function as to avoid dependency to Boost. Is there any resource where can I find such implementation? #include <boost/math/distributions/chi_squared.hpp> #include <boost/cstdint.hpp...
I'm developing a C++ program which has a "scan" method which will trigger a relatively long running scanning procedure. When the procedure is completed, the scan method will notify observers of results using the observer pattern. I would like to create a separate thread for each scan. This way I can run multiple scans simultaneously. W...
I'm running into some issues with boost::bind and creating threads. Essentially, I would like to call a "scan" function on a "Scanner" object, using bind. Something like this: Scanner scanner; int id_to_scan = 1; boost::thread thr1(boost::bind(&scanner::scan)); However, I'm getting tripped up on syntax. How do I pass the ...
I've recently managed to create a thread using the boost::bind function. For the time being, I'm having the thread display to stdout. I can see the output if I use thread.join. However, if I don't do this, I don't see any output. Why is this? I'm hoping I don't have to use the join function, because I would like to call this functi...
Is there a single-expression way to assign a scalar to all elements of of a boost matrix or vector? I'm trying to find a more compact way of representing: boost::numeric::ublas::c_vector<float, N> v; for (size_t i=0; i<N; i++) { v[i] = myScalar; } The following do not work: boost::numeric::ublas::c_vector<float, N> v(myScal...
I spent about 4 hours yesterday trying to fix this issue in my code. I simplified the problem to the example bellow. The idea is to store a string in a stringstream ending with std::ends, then retrieve it later and compare it to the original string. #include <sstream> #include <iostream> #include <string> int main( int argc, char** ...
The following template will decide if T is abstract with g++. /** isAbstract<T>::result is 1 if T is abstract, 0 if otherwise. */ template<typename T> class isAbstract { class No { }; class Yes { No no[3]; }; template<class U> static No test( U (*)[1] ); // not defined template<class U> static Yes test( ... ); // not d...
Hi, I'am trying to understand the example from program_options of the boost library (http://www.boost.org/doc/libs/1_38_0/doc/html/program_options/tutorial.html#id3761458) Especially this part: desc.add_options() ("help", "produce help message") ("compression", po::value<int>(), "set compression level") ; what exactly is he ...