From: "Ara.T.Howard" <ahoward@...>
Date: 2004-06-28T23:33:07+09:00
Subject: Re: Ruby Newbie: What if @ symbol is not used?

On Mon, 28 Jun 2004, Todd Gardner wrote:

> Hello Everyone,
>
> Pardon this newbie question.
>
> What if the @ symbol is not used before creating new variable names
> inside of methods?
>
> Thanks,
>
> Todd

then the variables are local to the method.  @vars are always instance vars of
the object - they persist after the method invocation and are availble to any
method of the object.  this analogy may help (although it is not really
correct):

   - @vars are 'global' within an instance of a class - an object.  all methods
     of the object may see this variable and have unrestricted read/write
     access to this @var.  other objects of the same class have their own
     unique copies of @vars however, and cannot see the @vars of other objects.

   - @@vars are 'global' to all instances of a class.  all objects of a given
     class may see this variable.  there is only one copy per class and all
     objects of that class may read/write @@vars.

   - 'normal' vars are just that, no special scoping rules, etc.  they are
     local to the method in which they were defined and leave scope (destroyed)
     after the method has ended.

cheers.

-a
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