regex object limitations/behavior for large regexes?

[Aaron Watters]

I'm thinking of a design which automatically generates
regex objects which are essentially disjunctions of simple
pattern alternatives.  The number of alternatives might
conceivably run into the thousands or more.

This raises the question: do regex objects behave nicely
when the regex gets very large?  Do they remain as fast?
Do they display reasonable (linear or n log n) memory
growth?  Do they just stop working at some point?

Please reply if you have any experience with very
large regexes or other insights.

Thanks in advance.  -- Aaron Watters

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