From: Andrew Johnson <ajohnson@...>
Date: 2004-03-03T01:54:48+09:00
Subject: Re: dynamic assignment of instance variables

On 2 Mar 2004 08:16:20 -0800, Gerard A.W. Vreeswijk <gv@cs.uu.nl> wrote:
[snip]
 
> Is it possible to set instances variables without eval or string
> interpolation?

I can see a couple of ways, so long as the right symbol is passed:

To set instance variables, pass in :@instance_variable symbols
and use #instance_variable_set(sym,val).  

  class Person
    def initialize(args)
      args.each do |sym,val|
        instance_variable_set(sym,val)
      end
    end
  end
  p Person.new(:@name => 'John', :@born => '2003')

Using accessors, pass in the :method= symbol and use
send(sym,val):

  class Person
    attr_accessor :name, :born
    def initialize(args)
      args.each do |k,v|
        send(k,v)
      end
    end
  end
  p Person.new(:name= => 'John', :born= => '2003')
  # or if you prefer:
  p Person.new(:name==> 'Fred', :born==> '2004')

regards,
andrew

-- 
Andrew L. Johnson   http://www.siaris.net/
      It's kinda hard trying to remember Perl syntax *and* Occam's
      razor at the same time :-)
          -- Graham Patterson