I'm looking at boost::lambda as a way to to make a generic algorithm that can work with any "getter" method of any class. The algorithm is used to detect duplicate values of a property, and I would like for it to work for any property of any class. In C#, I would do something like this: class Dummy { public String GetId() ... ...
I'm currently working on a server. I know that the client side is working (I can connect to www.google.com on port 80, for example), but the server is not functioning correctly. The socket has socket()ed, bind()ed, and listen()ed successfully and is on an accept loop. The only problem is that accept() doesn't seem to work. netstat sh...
When I call cin or getline with cin in my Visual Studio 2010 C++ app, I can enter something in the console (as it should be), but the right-click context menu is "blocked". It doesn't appear - this means I and my clients are not able to use copy and paste. How to enable the context menu in the console with cin? ...
Hello, I've a problem with SWIG and python. I've a c-class that compiles correctly, but the python script says it can't find the module. I compile with: swig -c++ -python codes/codes.i g++ -c -Wall -O4 -fPIC -pedantic codes/*.cc g++ -I/usr/include/python2.6 -shared codes/codes_wrap.cxx *.o -o _codes.so This gives me a _codes.so file...
I was calculating the Fibonacci sequence, and stumbled across this code, which I saw a lot: int Fibonacci (int x) { if (x<=1) { return 1; } return Fibonacci (x-1)+Fibonacci (x-2); } What I don't understand is how it works, especially the return part at the end: Does it call the Fibonacci function again? Could s...
C++0x thread library or Boost.thread define non-member variadic template function that lock all lock avoiding dead lock. template <class L1, class L2, class... L3> void lock(L1&, L2&, L3&...); While this function avoid help to deadlock, the standard do not includes the associated scoped lock to write exception safe code. { std::l...
This scoping problem seems like the type of C++ quandary that Scott Meyers would have addressed in one of his Effective C++ books. I have a function, Analyze, that does some analysis on a range of data. The function is called from a few places with different types of iterators, so I have made it a template (and thus implemented it in a...
I've got my interpreter up and running - quite bug-free and stable for now - now I want to add some visual options to my language to play around. What is a good GUI library easy to use and mainly easy to embed and "link" to my programming language? What general rules do I have to follow? I'm currently on XP with Microsoft Visual Stud...
Somewhere in lines of code, I came across this construct... //void* v = void* value from an iterator int i = (int)(long(v)) What possible purpose can this contruct serve? Why not simply use int(v) instead? Why the cast to long first? ...
I'm wondering how I could create a gradient wuth multiple stops and a direction if I'm making polygons. Right now I'm creating gradients by changing the color of the verticies but this is limiting. Is there another way to do this? Thanks ...
Hi, I am trying to compile the latest Boost c++ libraries for Centos. I 've used bjam install and it has placed the libraries in /usr/lib and /usr/lib64. The problem is I need the -mt variants for a specific application to run. I cannot understand in the documentation how to create the multithreading variants. :( Please give me a hint...
I need to download files/read strings from a specified url in C++. I've done some research with this, cURL seems to be the most popular method. Also, I've used it before in PHP. The problem with cURL is that the lib is huge, and my file has to be small. I think you can do it with winsock, but I can't find any simple examples. If you have...
Hello, I found the following graph libraries, but I am not sure which one I should use. Maybe there are some more... Graphviz (http://www.graphviz.org/) Boost Graph Library (http://www.boost.org/doc/libs/1_42_0/libs/graph/doc/index.html) Lemon (http://lemon.cs.elte.hu/trac/lemon) igraph (http://igraph.sourceforge.net/introduction.html...
At least some C preprocessors let you stringize the value of a macro, rather than its name, by passing it through one function-like macro to another that stringizes it: #define STR1(x) #x #define STR2(x) STR1(x) #define THE_ANSWER 42 #define THE_ANSWER_STR STR2(THE_ANSWER) /* "42" */ Example use cases here. This does work, at least i...
Right now I'v created a polygon, then I do the same thing but with line_loop to draw the outline. My issue right now is if I set the line thickness to high, the lines arn't connected. Their ends would need to be (linewidth) longer... is there a way to fix this? Thanks glMatrixMode (GL_PROJECTION); glLoadIdentity (); gl...
C++0x allows to lock on a mutex until a given time is reached, and return a boolean stating if the mutex has been locked or not. template <class Clock, class Duration> bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time); In some contexts, I consider an exceptional situation that the locking fa...
well I think I know what the problem is. I am just having a hard time debugging it. I am working with the directx api and I am trying to generate a plane along the x and z axis according to a book I have. The problem is when I am creating my indices. I think I am setting values out of the bounds of the indices array. I am just having a ...
So I'm aware that nothing is atomic in C++. But I'm trying to figure out if there are any "pseudo-atomic" assumptions I can make. The reason is that I want to avoid using mutexes in some simple situations where I only need very weak guarantees. 1) Suppose I have globally defined volatile bool b, which initially I set true. Then I la...
I have a quad and I would like to use the gradient it produces as a texture for another polygon. glPushMatrix(); glTranslatef(250,250,0); glBegin(GL_POLYGON); glColor3f(255,0,0); glVertex2f(10,0); glVertex2f(100,0); glVertex2f(100,100); glVertex2f(50,50); glVertex2f(0,100); glEnd(); //End quadrilateral coordinates gl...
I noticed that there are two ways to create C++ objects: BTree *btree = new BTree; and BTree btree; From what I can tell, the only difference is in how class objects are accessed (. vs. -> operator), and when the first way is used, private integers get initialized to 0. Which way is better, and what's the difference? How do you k...