Paul Hoffman phoffman at
Sun Mar 16 00:05:24 CET 2008

At 6:37 PM -0400 3/15/08, Patrik Fältström wrote:
>On 15 mar 2008, at 18.12, Paul Hoffman wrote:
>>So, putting the check for a character in C before the check for a 
>>character in I means that the check for the character in I will 
>>never happen if the character is in {Cf}. So, there is no need to 
>>define I, and nothing will ever be CONTEXTO. I don't think that is 
>>what you wanted.
>Ok, it goes back then to the earlier discussion on whether we should 
>have Cf still as CONTEXTO.
>What do you all say?

I say "huh?"

With the rules in the order you are proposing, there is no reason to 
have a CONTEXT0 because those characters are always DISALLOWED.

Further, the protocol document is unclear on what the difference 
between CONTEXT0 and CONTEXTJ is supposed to be in practice. Section says that the contextual rules for both types need to be 
tested; the bullets in Section 5.4 makes it seem like CONTEXT0 rules 
need to be found but not applied. Until this is clear, I doubt we can 
make a good decision on whether or not to have CONTEXT0.

Further still, with no examples of what the regular expressions that 
will be applied to the CONTEXT{J|0} characters are, thinking about 
this is all really abstract.

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