From: Robin <robninja@...>
Date: 2007-05-10T04:35:17+09:00
Subject: Re: Use of Double-Colon ::

On 9 May, 20:15, dbl...@wobblini.net wrote:
> Hi --
>
>
>
> On Thu, 10 May 2007, robni...@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)


Thanks everyone. That all makes sense.

I first met double-colon in the Class methods section of "why's guide
to ruby" ( http://poignantguide.net/ruby/chapter-3.html ), it  doesn't
mention using dot as an alternative in that section so I assumed
double-colon was the standard. Thanks for clearing it up.

Robin