From: Tim Pease <tim.pease@...>
Date: 2007-01-20T03:33:11+09:00
Subject: Re: Declaring instance variables dynamically

On 1/19/07, Ryan Davis <ryand-ruby@zenspider.com> wrote:
>
> On Jan 19, 2007, at 9:55 AM, Alex Schearer wrote:
>
> > Coming from PHP I want to take a class say,
> >
> > class User
> >     @name
> > end
> >
> > And call it:
> > u = User.new
> >
> > And then add a second class variable previously not declared:
> > u.mood = "happy"
> >
> > PHP being what it is, it let you declare public class variables in
> > that
> > manner.  Is there a way to acheive the same in Ruby?
>
> ri OpenStruct
>

http://www.ruby-doc.org/stdlib/libdoc/ostruct/rdoc/classes/OpenStruct.html

To elucidate a little more, OpenStruct is a great class that does what
you want ...

u = OpenStuct.new
u.name = 'bob'
u.mood = 'surly'

p u.name
p u.mood

u.freeze
u.age = 59    #=> raises TypeError


Blessings,
TwP