gets_is_weird.rb

# call as `ruby gets_is_wierd.rb some_nonexistant_file.txt`

filename = ARGV[0]

begin
  File.open(filename)
rescue Errno::ENOENT => e
  print "Rats. File not found. Try another: "
  # gets fails here because IO acts on the last file, not STDIN. 
  # chagning it to STDIN.gets works.
  # too much magic!
  filename = gets.chomp
  retry
end