8.6. Client-Side Inclusion
To do this, just wrap each line of the XHTML that your ordinary script would produce in a document.writeln( ) function:
document.writeln("<h1>This is the heading<h1>");
Now, have the script return this document as the result of a call by the script element from the HTML document. So, the HTML document contains this line:
<script src="Path to parsing script appended with feed URL" />
The CGI script returns the document.writeln script, which the browser executes, and then parses the resulting XHTML.
The upshot of this technique is that you can start a third-party RSS-parsing service with little effort. All you need to do is distribute the URL of the CGI script you are using and tell people to append the URL of the feed they want to the end of it. Give them the resulting script element to insert into their site code, and everyone is in business: