From: Rick DeNatale <rick.denatale@...>
Date: 2007-10-27T22:59:25+09:00
Subject: Re: find all member in a class

On 10/27/07, trebor777 <mrobert@trebor777.net> wrote:
>
>
>
> THUFIR HAWAT wrote:
> >
> > On Fri, 26 Oct 2007 20:58:01 +0900, Rick DeNatale wrote:
> >
> >
> >> class A
> >>   def i
> >>     @i ||= 42
> >>   end
> >
> >
> > Some rudimentary explanation please:
> >
> > the def is to define a method?
> > it's a coincidence that the method name is "i" and the instance variable
> > has the same name, "I"?
> >
> >
> > the third line declares an instance variable, "i", what do the "||" do in
> > that line, please?
> >
> >
> >
> > thanks,
> >
> > Thufir
> >
> >
> >
> >
>
>
>
> Yeap "def" is to define a method
> It could be a coincidence... or not, depends on what you want to do with
> this method... hum Here it's not a coincidence... this method return the
> value of the instance variable i (it's a reader accessor) or if it's nil,
> set it to 42 and return it.
>
> basically || means "if it's nil do that ", then = assigns the value 42 to @i

Correct, it's an attribute reader with lazy initialization of the
instance variable.

-- 
Rick DeNatale

My blog on Ruby
http://talklikeaduck.denhaven2.com/