From: dblack@...
Date: 2007-05-10T04:15:39+09:00
Subject: Re: Use of Double-Colon ::

Hi --

On Thu, 10 May 2007, robninja@gmail.com wrote:

> Hi,
>
> I'm new to Ruby and throughly enjoying learning the language. I'm
> currently working my way through the Pickaxe book, but have a couple
> of questions I hope someone can help me out with.
>
> As I understand it the double-colon ( :: ) can be used when calling
> class methods or class constants, but could correctly be replaced by a
> single dot ( . ) if preferred:
>
> SongList::is_too_long(song1)
> SongList.is_too_long(song1)
>
> I was wondering if someone more experience could tell me which method
> is used by the majority of Rubyists and whether it is thought of as
> "best practice" to use the double colon?
>
> I suspect this is probably down to personal preference. I personally
> prefer the double-colon but I would like to get into good habits now
> whilst I'm learning the language. The Pickaxe book doesn't use ::
> except when referring to modules (not sure if that is the correct
> term), e.g.,
>
> class TestRoman < Test::Unit::TestCase
>  #...
> end
>
> Could someone explain whether this is convention or if there is
> another reason for this?

I think it's clearer just to use a dot to mean "send this to the
object", and :: to drill down constant scope.  I don't think there's
any reason to use a different operator just because the receiver is a
class or module.  You're still doing the same thing: sending a message
to an object.  So I'd just use the dot.


David

-- 
Q. What is THE Ruby book for Rails developers?
A. RUBY FOR RAILS by David A. Black (http://www.manning.com/black)
    (See what readers are saying!  http://www.rubypal.com/r4rrevs.pdf)
Q. Where can I get Ruby/Rails on-site training, consulting, coaching?
A. Ruby Power and Light, LLC (http://www.rubypal.com)