Re: Non-deterministic content model

[Marcus Carr <mrc@allette.com.au>]

Jason Chalecki wrote:

> ((a, b)*, a) essentially represents the language where the first and
> last letter is a. Additionally, if there are b's, a and b must
> alternate. So (a, (b, a)*) matches the same language and is
> deterministic, correct?

Yes, but the original model was allowed to finish with either a or b - the
final a had a question mark. To model that with your approach would result
in (a, (b, a?)*), which allows a string of b's with no intervening a's.
Either way, you've changed the model.


--
Regards,

Marcus Carr                      email:  mrc@allette.com.au
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Allette Systems (Australia)      www:    http://www.allette.com.au
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"Everything should be made as simple as possible, but not simpler."
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