What if B::f would not have been marked virtual? Is the program ill-formed, then? Yes, it is. Because in order to override something, that something has to be virtual. Otherwise it’s not overriding, it’s hiding. So, the positive answer follows from the quote in your question.
The “virtual function table” or “virtual method table” is a list of method pointers that each class has. It contains pointers to the virtual methods in the class. Each instance of a class has a pointer to the table, which is used when you call a virtual method from the instance. This is because a … Read more
Did exactly what you are asking using the Github project: Microsoft/Windows-driver-samples/print/XPSDrvSmpl https://github.com/Microsoft/Windows-driver-samples/tree/master/print/XPSDrvSmpl Installer: http://wixtoolset.org/ Application: Listen to internal port Flow: Install printer and application from a single installer. User prints something with your driver while the application listens to the internal port. When data is sent the application picks it up. This is for XPS, … Read more
It works because the Standard says that’s how it should happen. I did some tests with GCC, and it turns out for virtual functions, GCC stores the virtual table offset of the function in question, in bytes. struct A { virtual void f() { } virtual void g() { } }; int main() { union … Read more
There’s been some research on this topic in the field of virtual machine design. Generally, a switch statement is going to be faster, a lot of virtual machines use switch semantics as opposed to virtual lookup. Theoretically, one would assume that a virtual table – being a constant time algorithm – will be faster, but … Read more
It depends on whether you want you derived behaviour to happen before or after the base behaviour. And don’t forget you can call the base method in the middle or not at all. Having said that, in general it will be called as the first thing. Because then your overriding method has the option to … Read more
Just tried: var schemaOptions = { toObject: { virtuals: true } }; and worked! 😉 Now by default I use: var schemaOptions = { toObject: { virtuals: true } ,toJSON: { virtuals: true } };
I think the best approach would be to combine HTML5 form attributes with an optional virtual keyboard link. HTML5 form attributes can be used to trigger different types of keyboards. For example, <input type=”email”>, <input type=”number”> and <input type=”tel”> will trigger the appropriate keyboard types on iOS (not sure about Android/WinPho/other, but I would imagine … Read more
virtual means the method called will be chosen at run-time, depending on the dynamic type of the object. static means no object is necessary to call the method. How do you propose to do both in the same method?
The domain name part of the path is not really a property of the application itself, but depends on the requesting URL. You might be able to reach a single Web site from many different host names. To get the domain name associated with the current request, along with the virtual path of the current … Read more