From: Carlos <angus@...>
Date: 2004-03-09T04:23:29+09:00
Subject: Re: How to remove an instance variable ?

[Its Me <itsme213@hotmail.com>, 2004-03-08 19.54 CET]
> So "@a" refers to (and creates if needed) an instance variable.
> 
> Is there some method to get rid of an instance variable (not just set to
> nil)?

$ ri -T remove_instance_variable
---------------------------------------- Object#remove_instance_variable
     obj.remove_instance_variable(symbol)    => obj
------------------------------------------------------------------------
     Removes the named instance variable from _obj_, returning that
     variable's value.

        class Dummy
          attr_reader :var
          def initialize
            @var = 99
          end
          def remove
            remove_instance_variable(:@var)
          end
        end
        d = Dummy.new
        d.var      #=> 99
        d.remove   #=> 99
        d.var      #=> nil