From: Paul Lutus <nospam@...>
Date: 2006-09-03T03:00:31+09:00
Subject: Re: Class behaviour

Geoff Barnes wrote:

> Just curious, can I write a class that can check values as they are
> assigned to objects?

Sure, just declare accessors in the usual way, then write your own methods
to check the values:

------------------------------------

#!/usr/bin/ruby

class Suspicious
   attr_accessor :a
   def a=(v)
      raise "Number Range Error" if v < 0 || v > 5
      @a = v
   end
end

s = Suspicious.new

s.a = 10 # number range error

puts s.a # never gets here

------------------------------------

-- 
Paul Lutus
http://www.arachnoid.com