From: Gavin Kistner <gavin@...>
Date: 2005-08-22T02:29:32+09:00
Subject: Re: include and extend Module - Ruby Way

On Aug 21, 2005, at 9:04 AM, Alexandru Popescu wrote:
>> Sorry, I don't know Java (any more). Are you describing a global   
>> function that is only available to instance methods of a certain   
>> class, which is invoked without an explicit receiver?
>>
>
> Nope. I was talking about:
> [code]
> public class ExampleClass {
>     public static void staticMethod() {
>         // illegal access to any instance field
>         System.out.println("staticMethod");
>     }
> }
>
> ExampleClass.staticMethod(); // prints the message; no instance of  
> ExampleClass is available
> ExampleClass ec= new ExampleClass();
> ec.staticMethod(); // prints the message; not recommended but works

I don't know of a built-in mechanism to do this in Ruby, other than  
something like:

class Foo
     def self.staticMethod
         puts "staticMethod"
     end
     def staticMethod
         self.class.staticMethod
     end
end

There are things you could do to make it easier to set this up, so  
you might only have to type something like:
class Foo
     static_method :foo {
         # your_code_here
     }
end
but that would just be a fancy interface to setting up a method on  
both the class and its instances.


You say that it's not recommended, so I gather this isn't a big  
issue. Is there some specific use case where you find this useful?