From: Jeff Wood <jeff.darklight@...>
Date: 2005-09-29T09:15:57+09:00
Subject: Re: Python to Ruby: Two puzzlements...

oops, that should have been

attr_accessor :a

( which is again a method call against self which because it's inside
of a class definition *IS* the class object that's being
built/modified )

j.

On 9/28/05, Jeff Wood <jeff.darklight@gmail.com> wrote:
> Actually everything you do in ruby has a receiving object reference
> under the covers...
>
> if you do obj.method you are explicitly setting the receiving object
> ... Other wise, it's always implicitly SELF
>
> And to mess with your brain a bit more, you can do an instance_eval
> where you set self to some other object ...
>
> class Blah
>     attr_accessor: a
> end
>
> obj1 = Blah.new
> obj2  = Blah.new
>
> obj1.instance_eval do
>   @a = 1
> end
>
> obj2.instance_eval do
>   @a = 2
> end
>
> ... remember that there are actually VERY few keywords in Ruby....
> everything else is a method on some object in the system ...
>
> when you define functions in a script outside of a class definition,
> self is still there for a silent single instance of Object that wraps
> everything in your script.
>
> ... once you get used to that, it's pretty happy sailing.
>
> Welcome to Ruby ... we hope you enjoy the ride.
>
> j.
>
> On 9/28/05, Elf M. Sternberg <elf@drizzle.com> wrote:
> > James Edward Gray II <james@grayproductions.net> writes:
> >
> > > On Sep 28, 2005, at 1:46 PM, Elf M. Sternberg wrote:
> >
> > > Welcome to Ruby.  Hopefully it will stop baffling you very soon now.  ;)
> >
> >         Thank you. One can only hope.
> >
> > > > The first is from
> > > > http://redhanded.hobix.com/bits/hyperextended.html, and my question is
> > > > about the 'extend' keyword there.  Where does that came from?  In what
> > > > object is it defined?
> >
> > > It is defined in Object.
> >
> >         I guess I'm just surprised by the implicit reference.  In Python
> > (and Perl, to an even greater if more obscure degree) extensions like
> > that are quite explicit.  It is not immediately obvious to me that
> > 'extend' is a part of Object.
> >
> >         It's all a matter of familiarity.  I wouldn't be surprised to
> > see something more like self.extend(...), but the 'extend ...' just
> > seems rather unattached.
> >
> >         For what it's worth, this is making some *very* cobwebbed
> > portions of my brain think, "Y'know, this looks like ObjC (circa 1996,
> > via Webobjects) on drugs."
> >
> > > > I'm guessing that the "%r" and "%w" are the ruby equivalents of perl's
> > > > qr{} and qw{} constructs
> > >
> > > Bingo.
> >
> >         That part's easy enough.  Thanks!
> >
> >                 Elf
> >
> >
>
>
> --
> "http://ruby-lang.org -- do you ruby?"
>
> Jeff Wood
>


--
"http://ruby-lang.org -- do you ruby?"

Jeff Wood