JavaScript – How to Name a Private Method in a Language Without Privacy Support

classjavascriptnaming

What's the coding standard for naming a private method in a language which does not have the private modifier? Specifically, I am talking about Javascript. Below I've placed an underscore at the end of my private method's name, but a colleague told me that underscore is usually for class fields.

var MyClass = Class.create({
    initialize: function() {
        alert('constructor');
    },
    publicMethod: function() {
        alert('i am public');
    },
    privateMethod_: function() {
        alert('i am private');
    }
});

Best Answer

As everyone told you in a comments, most people(and some languages) use single underscore.

Related Solutions

Naming Conventions – What Language to Use for Business Class Names?

I'm working in Germany and I prefer to pick English.

Sometimes e.g. domain specific things like creating an module to "DATEV" (german invoice/billing software) I do use German names. Some German words cannot be translated properly, e.g. "Referenzbuchungsnummer" (ReferenceBookingNum?) or "Sachkontenlaenge" (..?). Also I do think that domain specific things would be ending in maintenance horror. Maybe you would remember that ReferenceBookingNum would relate to "Referenzbuchungsnummer", but what about your co-workers? They have to study internal documentation about naming, if documentation exists. They won't be very familiar with the module without having proper names. It's an unnecessary complexity if all other developer are German too. But "CakeFactory" sounds much better than "KeksFabrik" ;)

So it all depends.

C++ – Unit Test Private Method Using a Friend Class

An alternative to friend (well, in a sense) that I use frequently is a pattern that I've come to know as access_by. It's pretty simple:

class A {
  void priv_method(){};
 public:
  template <class T> struct access_by;
  template <class T> friend struct access_by;
}

Now, suppose class B is involved in testing A. You can write this:

template <> struct access_by<B> {
  call_priv_method(A & a) {a.priv_method();}
}

You can then use this specialization of access_by to call private methods of A. Basically, what this does is put the onus of declaring friendship into the header file of the class that wants to call A's private methods. It also lets you add friends to A without changing A's source. Idiomatically, it also indicates to whoever reads the source of A that A does not indicate B a true friend in the sense of extending its interface. Rather, the interface of A is complete as given and B needs special access into A (testing being a good example, I've also used this pattern when implementing boost python bindings, sometimes a function that needs to be private in C++ is handy to expose into the python layer for the implementation).

Best Answer

Related Solutions

Naming Conventions – What Language to Use for Business Class Names?

C++ – Unit Test Private Method Using a Friend Class

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