There was an interesting problem in C++, but it concerns more likely architecture. There are many (10, 20, 40, etc) classes that describe some characteristics (mix-in classes), for exmaple: struct Base { virtual ~Base() {} }; struct A : virtual public Base { int size; }; struct B : virtual public Base { float x, y; }; struct C : virt...
Today I stumbled over a piece of code that looked horrifying to me. The pieces was chattered in different files, I have tried write the gist of it in a simple test case below. The code base is routinely scanned with FlexeLint on a daily basis, but this construct has been laying in the code since 2004. The thing is that a function implem...
I am using IXMLDOMNodeListPtr , IXMLDOMNodePtr , IXMLDOMElementPtr and IXMLDOMDocPtr. I am having little confusion over here i.e. Should i have to call Release() on these pointers before they go out of scope. Thanks. ...
Here's a"dumb question : can two jstrings be compared in JNI ? if so how ? ...
I'm looking for a C++ library which allows for easy integration of Coordinate Transformation Matrices (CTM) in my application. You might know CTMs from PDF or PostScript. For one project we are using C++/Qt4 as a framework, which offers a QTransform class, which provides methods like .translate(double x, double y) or .rotate(double degr...
Hello, I have a setup for using UnitTest++ like this in VS2008. Sometimes the cmd window, which shows the console output of the unit tests just hangs. I can move the window, resize and stuff, but I'm unable to close it. I see the window in the App tab of the Task Manager, but not in the Process tab, "Switch to process" doesn't work e...
Hello. Could anyone please explain the following line of code, found on http://docs.openttd.org/ai__cargo_8cpp_source.html return (AICargo::TownEffect)::CargoSpec::Get(cargo_type)->town_effect; If this line was: return (AICargo::TownEffect) ::CargoSpec::Get(cargo_type)->town_effect; (note the space between TownEffect) and the ::) t...
Hi everyone! I am implementing, a distributed cache proxy server.I have an idea of the HTTP and related stuff, so i am rather concentrating on the sub part "Distributed data storage". From some search on web i found that this could be done using Distributed Hash Tables(DHT). I was wondering if there exists some kind of library for this...
Hello, I'm working on C++ project that is supposed to run on both Win32 and Linux, the software is to be deployed to small computers, usually working in remote locations - each machine likely to contain it's own users/service-men pool. Recently, our client has requested that we introduce access control via password protection. We are...
Hi, I am writing Firefox extension using C++. I am enumerating the tabs to get their respective URLs. Following is pseudocode: nsCOMPtr<nsIWindowMediator> windowMediator = do_GetService(NS_WINDOWMEDIATOR_CONTRACTID, &rv); windowMediator->GetMostRecentWindow(L"navigator:browser", getter_AddRefs(dwi)); dwi->GetDocument(getter_AddRefs(d...
Given a integer number and its reresentation in some arbitrary number system. The purpose is to find the base of the number system. For example, number is 10 and representation is 000010, then the base should be 10. Another example: number 21 representation is 0010101 then base is 2. One more example is: number is 6 and representation os...
I have a pre-existing c++ object model which represents the business layer tier of an application. I want to be able to expose the object model to applications written in other languages i.e vbscript, VB, javascript etc. I believe the best way of doing this is to wrap the business objects with a COM layer. What fast and effective method...
This was a bug I found in a server application using Valgrind. struct Foo { Foo(const std::string& a) : a_(a_) { } const std::string& a_; }; with gcc -Wall you don't get a warning. Why is this legal code? ...
I am trying to retrieve the monitor ID's as shown in the Windows display properties (#1, 2... etc), but I can't seem to find a way. I have tried using EnumDisplayMonitors as well as EnumDisplayDevices. They both return something like "\.\DISPLAY1". However, this number doesn't always match the number shown by Windows, especially when 2 v...
Hi, I wanted to store 10 in 4th position of array of 5 positions. How to do ? int main( ) { int a[5] = {,,,,4} ; return 0; } If i do that i get error. Please help. Thanks in advance. ...
Is it possible to forward-declare a nested class, then use it as the type for a concrete (not pointer to/reference to) data member of the outer class? I.E. class Outer; class Outer::MaybeThisWay // Error: Outer is undefined { }; class Outer { MaybeThisWay x; class MaybeThatOtherWay; MaybeThatOtherWay y; // Error: MaybeThatOt...
Hi. I have some strange linking problem in my Visual Studio 2005 C++ project. As always, I declare class in a header and define it's methods in cpp. A have all these files included in my project. And I still have the unresolved external symbol calcWeight. It appears if I actually use this class in my main function. calcWeight() is decla...
I am trying to write a generic allocator class that does not really release an object's memory when it is free()'d but holds it in a queue and returns a previously allocated object if a new one is requested. Now, what I can't wrap my head around is how to pass arguments to the object's constructor when using my allocator (at least withou...
I have a structure of base class and a couple of inherited classed. Base class should be pure virtual class, it should prevent instantiation. Inherited classes can be instantiated. Code example below: class BaseClass { public: BaseClass(void); virtual ~BaseClass(void) = 0; }; class InheritedClass : public BaseClass { public: ...
Is there a tutorial/reference for creating an ActiveX DLL in Visual Studio 2008 C++ ? I've got a DLL built with the DLLRegisterServer/UnregisterServer, and it's registered, but I'm having a little trouble figuring out what name to use to reference it (from a vbscript) and how to make sure my functions are exported correctly. Do I have ...