From: Eric Armstrong <Eric.Armstrong@...>
Date: 2006-06-22T10:19:00+09:00
Subject: Surprise? ARGV[0] undefined after processing ARGF

I found this behavior surprising. Is it
intentional (and therefore something I need
to understand better), or is it a bug:

     print_usage if ARGV[0] == nil
     puts ARGV[0]  # => filename

     # Parse the document
     @doc = Document.new ARGF.read()
     puts ARGV[0]  # => nil