From: Phlip <phlip2005@...>
Date: 2008-09-09T10:19:18+09:00
Subject: Re: Why is Ruby dynamic?

Zhao Yi wrote:
> People say Ruby is a dynamic language. I don't understand what the
> "dynamic"　mean here. Does this mean Ruby can dynamic change itself at
> run-time?

It means Ruby can change its objects at runtime. For example:

   class Narcissus
     def call_once
       eval '
         class Narcissus
           def call_once
             raise "nope!"
           end
         end'
     end
   end

The first time you call Narcissus.new.call_once, it will not raise. The second 
time, it will raise "nope!". Ruby allows class definitions to change on the fly.

-- 
   Phlip