I searched around but could not find any clues.
I am messing around with the vCard RFC and have stumped myself trying to come up with a recursive parser that allows for (nearly) infinite depth. This is required by the RFC: some of the properties of a vCard allow another vCard as their value -- wha wha :/.
In simplicity the structure is like this (not a correct vCard by a long shot but illustrates the problem):

BEGIN:VCARD
FN:Fee
AGENT:
BEGIN:VCARD
FN:Fie
AGENT:
BEGIN:VCARD
FN:Foe
AGENT:
BEGIN:VCARD
FN:Fum
END:VCARD
END:VCARD
END:VCARD
END:VCARD

[download]

and what I am looking for is each AGENT to be a hash reference to the card inside of it such that I can refer to Fum like:

$card{AGENT}{AGENT}{AGENT}{FN};

[download]

I don't need the exact solution as I am willing to learn it (although I won't stop you) -- I just need some pointers to recursive parsing techniques.

Thanks!

In reply to recursive parsing techniques by blahblah

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