You really need to clarify, since the answer to any plausible meaning I can infer from your question is Yes!" All that's required is that you apply yourself to specifying the steps by which you'd do this if the file were a book; searching this site (and others) for keywords growing out of that exercise (restricting the search to Perl) and learning how to tell Perl to do what you want.

So please, expand and be explicit: does "subcontents" equal the various fragments (elements of an array) created by splitting on blank lines? If so, how do those elements, "held in memory" fail to satisfy your requirements? What processing do you have in mind that has to occur "as if they were infactfiles?" What is the desired outcome? What's the big picture on your (woefully inadequate, to date) specs?

And what research (asking the question in the CB and repeating it as a SOPW question doesn't count) have you done to find your own solution.