overloading

问题 I am trying to learn C and am very confused already. In the OOP languages i have used there exists the ability to perform method overloading, where the same function could have different parameter types and call whichever was the most appropriate. Now in C i know that this is not the case so i cant figure out the following problem, How printf() works. For example: char chVar = 'A'; int intVar = 123; float flVar = 99.999; printf("%c - %i - %f \n",chVar, intVar, flVar); printf("%i - %f - %c \n"

问题 I am trying to learn C and am very confused already. In the OOP languages i have used there exists the ability to perform method overloading, where the same function could have different parameter types and call whichever was the most appropriate. Now in C i know that this is not the case so i cant figure out the following problem, How printf() works. For example: char chVar = 'A'; int intVar = 123; float flVar = 99.999; printf("%c - %i - %f \n",chVar, intVar, flVar); printf("%i - %f - %c \n"

问题 New to python and this might be a silly question, but how does one properly implement the repr method? I wrote a quick little program to simulate a game of cards but I don't know what to write for the repr method. The repr method for the Card class was pretty straight forward, but I don't know what to do for the DeckOfCards class Here's my code: import random class Card: '''Create a single card, by id number''' # Class variables, created once for the class suits = [ '\u2660', '\u2661', '

问题 ostream& operator <<(ostream& osObject, const storageRentals& rentals) { osObject << rentals.summaryReport(); return osObject; } summaryReport() is a void function, and it is giving me an error: no operator "<<" matches these operands but the error is not there if I change the summaryReport function to an int , but the problem I have with that is you have to return a value, and it is printing it out on the screen. void storageRentals::summaryReport() const { for (int count = 0; count < 8;

问题 I got the answer NO! Because passing by value and passing by reference looks identical to the caller. However, the code below compiles right class A { public: void f(int i) {} void f(int& i) {} }; But when I try to use it, there is compile error. int main () { A a; int i = 9; int& j = i; a.f(1); a.f(i); a.f(j); return 0; } Why does not the compiler disable it even without knowing it is going to be used? 回答1: Yes, they can be overloaded based on reference or not. That is why it's perfectly

问题 Trying to convert some java to scala code I face the problem of a different method signature which compiled fine in the java world: The following code in java (from https://github.com/DataSystemsLab/GeoSpark/blob/master/babylon/src/main/java/org/datasyslab/babylon/showcase/Example.java#L122-L126) visualizationOperator = new ScatterPlot(1000,600,USMainLandBoundary,false,-1,-1,true,true); visualizationOperator.CustomizeColor(255, 255, 255, 255, Color.GREEN, true); visualizationOperator

问题 I want to overload any operator . i want to do such a simple function that for instance think about overloading of == operator .Overload == such that x==y returns x . Or x==y return x+y. It doesn't matter what . Can you show me any simple operator overloading example? I cannot find any example on the web unfortunately. For example;when i call Tree a == Tree a return 5 (it always return 5. I select it ,it is not related to any thing) or when i call 3==4 return : 7 I tried the below codes(i

问题 How can I overload a method that takes a Generic List with different types as a parameter? For example: I have a two methods like so: private static List<allocations> GetAllocationList(List<PAllocation> allocations) { ... } private static List<allocations> GetAllocationList(List<NPAllocation> allocations) { ... } Is there a way I can combine these 2 methods into one? 回答1: Sure can... using generics! private static List<allocations> GetAllocationList<T>(List<T> allocations) where T :

问题 I suspect the prototypes of fill constructor and range constructor of std::vector (and many other STL types) given in this webpage are not right, so I implement a NaiveVector to mimic these two prototypes. My code is: #include <iostream> #include <vector> using namespace std; template <typename T> struct NaiveVector { vector<T> v; NaiveVector(size_t num, const T &val) : v(num, val) { // fill cout << "(int num, const T &val)" << endl; } template <typename InputIterator> NaiveVector

问题 This question already has answers here : How could comma separated initialization such as in Eigen be possibly implemented in C++? (3 answers) Closed last year . I just want to know if we can give two or more parameters to an overload of operator << An example will be more explicit: anyType operator<<(arg p1, arg p2) { DoSomethingWith(p1); DoSomethingWith(p2); return (*this); } And use it like this: anyVar << anyVar2, anyVar3; 回答1: No, that is not possible. The closest you can come would be