overriding

问题 SO!!! I added zfcUser module (but I want to do this with any other module too) to my project, based on Zend Framework 2.*. How I can override controllers/views/configs of this module, so changes of them wouldn't be deleted with updating dependencies with composer (I tried to do this and didn't found files are chaned, but what if.... Oo). I know that there are the way existing to do this, but I don't know it. View Helper? Or what? Help me, please! Thank you. ADDITIONAL INFO Current folders and

问题 I have code that I want to make the following changes: How do I override ToString()? It says: A static member ...ToString(System.Collections.Generic.List)' cannot be marked as override, virtual, or abstract. How do I make it generic? public static override string ToString(this List<int> list) { string output = ""; list.ForEach(item => output += item.ToString() + "," ); return output; } Thanks! 回答1: What are you trying to achieve? Often I want to output the contents of a list, so I created the

问题 I have an ActiveSupport::Concern module which looks roughly like the following: module MyModel module Acceptance extend ActiveSupport::Concern included do enum status: [:declined, :accepted] end def declined! self.status = :declined # some extra logic self.save! end def accepted! self.status = :accepted # some extra logic self.save! end end end This is only ever going to be included into ActiveRecord classes, hence the use of enum . Basically, I'm overriding the declined! and accepted!

问题 Is it always necessary to follow the sealed keyword with override in the signature of a method like the below code: public sealed override string Method1(){.....} I mean, if I want to "seal" the method within the base class without overriding, is the override keyword still necessary? 回答1: Sealing a method only makes sense if you override it. What happens here is the following: You are overriding a method from a base class ( override ) and tell the compiler that classes derived from your class

问题 Basically, I want the C# compiler functionality of its override keyword in my C++ code. class Base { virtual int foo(int) const; }; class Derived : public Base { virtual int foo(int); // wanted to override Base, but forgot to declare it const }; As we all know, the above code will compile fine, but yield some strange runtime behavior. I would love my C++ compiler to catch my poor implementation with something like C#'s override keyword. Are there any keywords like "override" being introduced

问题 class Base { public: Base() { cout<<"base class"<<endl; fun(); } virtual void fun(){cout<<"fun of base"<<endl;} }; class Derive:public Base { public: Derive() { cout<<"derive class"<<endl; fun(); } void fun(){ cout<<"fun of derive"<<endl;} }; void main() { Derive d; } The output is: base class fun of base derive class fun of derive Why the second line is not fun of derive ? 回答1: When you call fun() in the base class constructor, the derived class has not yet been constructed (in C++, classes

问题 I understand the purpose of the C++ override, however am a bit confused by it's implementation compared to other higher level languages, where its use is required by default. The C++11 wiki page describes it as a "technically identifier for declarator attribute" but does not elaborate as to why it is not simply a keyword for the language. 回答1: It is optional to maintain backwards compatibility with C++03. Making it non-optional would have broken all the code * . Similarly, making override a

问题 In the following simple code fragment: #include <cstddef> struct B { virtual ~B() = default; static void operator delete(void *, int); static void * operator new(size_t, int); }; struct C : B { virtual ~C() = default; }; clang 3.7 complains that "non-deleted function '~C' cannot override a deleted function": http://goo.gl/Ax6oth Neither Visual Studio nor GCC report an error in this code. Is it a clang defect or what? 回答1: static void operator delete(void *, int); No, it's static void operator

问题 I know that the override contextual keyword was introduced to write safer code (by checking for a virtual function with the same signature) but I don't feel good about it, because it seems to be redundant for me to write override every time I want to override a virtual function. Is it a bad practice to not use override contextual keyword for 99% of cases? Why/when should I have to use it ( a compiler warning is not enough when we are hiding a virtual function mistakenly )? EDIT: In other

问题 This question already has answers here : java compiled classes contain dollar signs (4 answers) Closed 6 years ago . When i compile my java Enum Day, it generates his Day.class file and 8 Day$#.class Files, so i want to know why the compiler generates 8 $#.class instead of 7, because i have 7 enum constants, but 8 override annotations, i have understood that the Dollar.class files are generated for every inner class or by enum constants, but what about the eight .class file what it is