[pmwiki-users] Including a file with PmWiki markup

[Michael Benjamin]

How can I include a file containing PmWiki markup into a page?
For example, I'm looking to include a file such as:

------------------------- file foobar.txt
!! Introduction
Hello World
[[<<]]
Good bye
------------------------

I've tried (:includefile:) and even (:includeupload), but both just
include the text verbatim without converting [[<<]] to a newline etc,
or the !! as a section heading.

Thanks,
Mike