From: Jan Svitok <jan.svitok@...>
Date: 2006-11-24T07:28:48+09:00
Subject: Re: double-slashes in input causing trouble

or you can use references:

old_section = $1
new_body = body.sub(old_section, bit_at_top + '\&')

\& = the last match.

if there was gsub instead of sub, this would be slower as the
replacement takes place on every occurence. In this case, however,
there's max 1 occurence.

You can do as well:
- body = ""
- File.open(input, 'r') do |file|
-   body = file.read
- end
+ body = File.read(input)

and

    File.open(input,'w') do |file|
      file.write new_body
-   end
+   end unless new_body == body