overloading

问题 This question already has answers here : Why does an overridden function in the derived class hide other overloads of the base class? (4 answers) Closed 4 years ago . Given the following... #include <iostream> using namespace std; class BaseClass { public: void Func(float f) { cout << "BaseClass:Func() called!"; } }; class SubClass : public BaseClass { }; int main() { SubClass sub; sub.Func(1.1f); return 0; } This runs pretty much as one would expect, resulting in the following output...

问题 See below simple snippet: public class GenericsOverloadingDistinguish<T> { public void print1(T t) { System.out.println("t"); } public void print1(Integer i) { System.out.println("integer"); } } public static void main(String[] args) { new GenericsOverloadingDistinguish<Integer>().print1(new Integer(1)); } This would cause an ambiguous method call and will not compile. This is utterly confusing on the user of that class. It is not able to call neither print1(T t) nor print1(Integer i) simple

问题 I have the following test code: #include <string> #include <iostream> class CString { public: CString(char const*) {} }; class TestBed { public: void Comparison(CString const&) { std::cout << "CString Overload" << std::endl; } void Comparison(std::string const&) { std::cout << "std::string overload" << std::endl; } }; int main() { TestBed tb; tb.Comparison("Hello World"); } This code fails to compile because the call to Comparison() is ambiguous. I expect this behavior. However, when I make

问题 Is there a way to control the order of some classes methods in the vfptr? It seems that Visual C++ 2010 at least puts the method pointers in the declaration order, except for overloaded methods. Below is sample code: enum ENUM { }; class CLASS { virtual void foo1() { }; virtual CLASS& __cdecl operator<<(const ENUM x) { return *this; }; virtual void foo2() { }; virtual CLASS& __cdecl operator<<(const char* x) { return *this; }; virtual CLASS& __cdecl operator<<(int x) { return *this; };

问题 Consider the following code: #include <iostream> #include <type_traits> struct A; template<class T> concept HasParent = std::is_convertible_v<typename T::parent*, A*>; struct A{}; struct B : A { using parent = A; }; template<class T> int foo(T*) { return 1; } template<HasParent T> int foo(T*) { // call the other one? return 2; } int main() { B b; std::cout << foo(&b) << std::endl; // displays 2 return 0; } Is it possible to call the general foo<T>(T*) function from foo<HasParent T>(T*) ?

问题 Consider the following code: #include <iostream> #include <type_traits> struct A; template<class T> concept HasParent = std::is_convertible_v<typename T::parent*, A*>; struct A{}; struct B : A { using parent = A; }; template<class T> int foo(T*) { return 1; } template<HasParent T> int foo(T*) { // call the other one? return 2; } int main() { B b; std::cout << foo(&b) << std::endl; // displays 2 return 0; } Is it possible to call the general foo<T>(T*) function from foo<HasParent T>(T*) ?

问题 I am working on building Istio-envoy on rhel7.6:ppc64le . The build passes, however there are test failures: Error: In file included from test/server/filter_chain_benchmark_test.cc:19:0:` `bazel-out/ppc-fastbuild/bin/external/com_github_google_benchmark/_virtual_includes/benchmark/benchmark/benchmark.h:1071:16: error: 'virtual void benchmark::Fixture::SetUp(benchmark::State&)' was hidden [-Werror=overloaded-virtual]` `virtual void SetUp(State& st) { SetUp(const_cast<const State&>(st)); }` ` ^

问题 Say I want to check if a string contains any of the letters in "cory": def hasCory(input: String): Boolean = { val myName = "cory" input.exists(myName.contains) } The compiler complains with: error: type mismatch; found : CharSequence => Boolean required: Char => Boolean Scala provides the Char -accepting method I want in StringOps: But it appears that the compiler cannot see this method unless I change the code to one of: input.exists(myName.contains(_)) input.exists(c => myName.contains(c))

问题 This question already has answers here : How do you specify a byte literal in Java? (6 answers) Closed 9 months ago . Explain me please, why, when I write 4 overloaded methods and call it => it chooses method with 'int' as default, but not 'byte', which is closer/better, because it can storage values from -127 to 128? class Main { public static void method(short s) { System.out.println("short"); } public static void method(byte b) { System.out.println("byte"); } public static void method(int

问题 As the title says. From what I can see online the Overloads keyword is optional but is there ever a time when it is necessary? It even seems to be an error when used in a Module. 回答1: No, it's not neccessary. You can overload methods and properties without the Overloads keyword. However, if you use the Overloads or Overrides keyword on one overload of a method, you have to use it on all other overloads to that method in the class. You can use the Overloads keyword instead of the Shadows