encapsulation

In this answer to the question " Why can't my object access protected members of another object defined in common base class? ", one can read: You can only access protected members from your own base class instance. Either I don't get it correctly or the following MCVE (live on coliru) proves it wrong: struct Base { void f(); protected: int prot; }; struct Derived : Base { void g(); private: int priv; }; void Base::f() { Base b; b.prot = prot; (void) b; } void Derived::g() { { Derived d; (void) d.priv; } { Derived& d = *this; (void) d.priv; } { Derived d; (void) d.prot; // <-- access to other

I've been working with the Joomla framework and I have noticed that they use a convention to designate private or protected methods (they put an underscore " _ " in front of the method name), but they do not explicitly declare any methods public , private , or protected . Why is this? Does it have to do with portability? Are the public , private , or protected keywords not available in older versions of PHP? public, private and protected are PHP5 keywords. unfortunately, PHP4 still has a very high install base (especially amongst shared hosting services). here's a pretty pic showing july usage

Let's say I have a need for a simple private helper method, and intuitively in the code it would make sense as an extension method. Is there any way to encapsulate that helper to the only class that actually needs to use it? For example, I try this: class Program { static void Main(string[] args) { var value = 0; value = value.GetNext(); // Compiler error } static int GetNext(this int i) { return i + 1; } } The compiler doesn't "see" the GetNext() extension method. The error is: Extension method must be defined in a non-generic static class Fair enough, so I wrap it in its own class, but still

I have an experience with the C# programming language, but I also have to work with the JS now and it's rather new for me. I have tried to develop a simple class emulation in JS, like this: http://jsfiddle.net/T74Zm/ function A( inputValue ) { this.Init( inputValue ); this.Print(); } A.prototype = { value: null, Init: function( inputValue ) { this.value = inputValue; }, Print: function () { console.log( this.value ); } } var obj = new A(40); I've tried to encapsulate the variable value in A.prototype , but it seems to be by JavaScript specification that all objects are available. So my

New to C#, and I understand that encapsulation is just a way of "protecting data". But I am still unclear. I thought that the point of get and set accessors were to add tests within those methods to check to see if parameters meet certain criteria, before allowing an external function to get and set anything, like this: private string myName; public string MyName;// this is a property, speical to c#, which sets the backing field. private string myName = "mary";// the backing field. public string MyName // this is a property, which sets/gets the backing field. { get { return myName; } set { if

I have a class structure which represents (internally) the data I wish to output to a file. Some of the member variables are private to the data class so that it can manage itself and stop things going awry. I then want this data to be output into a number of file formats. I could do something like savefile_formatA(DataClass* pDataClass, ofstream& fout); savefile_formatB(DataClass* pDataClass, ofstream& fout); except that the functions need to then see the private member variables of DataClass . I could of course just make savefile_formatXYZ() friend functions but then I would need to add a