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RE: Grammar for IPv6 address


From: Hans Aberg
Subject: RE: Grammar for IPv6 address
Date: Wed, 7 Jul 2004 19:08:45 +0200

Also to me, it looks as though you would get best help from the
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Once you have gotten your lexer to identify the ipv4address, you can let
the parser do the more advanced parsing.

Specifically, I figure that the ipvX addresses cannot contain spaces, but
that the grammar in which they are contained can do it, used to separate
tokens. So it is the better letter to let the lexer identify the parts
which cannot contain spaces as tokens.

At 10:28 -0400 2004/07/07, Jeganatan, Srividhya wrote:
>Not really.My intent is to define policy rules that filter routes based on
>an ipv6 address.
>As far as I know, I need bison to define these rules.
>With the token defined as one string of 4 hex digits, now I need to define a
>rule that takes different combinations of 4 digit strings to form an ipv6
>address.
>
>For example, for an ipv4 address, a rule can be defined as:
>ipv4address: <number> '.' <number> '.' <number> '.' <number>
>               |
>               <number> '.' <number> '.' <number>
>               |
>               <number> '.' <number>
>               |
>               <number>
>
>this will then be used for the ipv4prefix along with a '/' and a prefixlen.
>
>I am trying to define similar rules to parse an ipv6prefix (address and
>prefixlen)
>
>Thanks
>SV
>
>-----Original Message-----
>From: Urdaneta, Alfonso E (N-Summitt Technologies)
>[mailto:address@hidden
>Sent: Wednesday, July 07, 2004 10:18 AM
>To: Jeganatan, Srividhya; address@hidden
>Subject: RE: Grammar for IPv6 address
>
>
>> I'm trying to define grammar rules for IPV6 addresses.
>
>Your question is probably more likely to get an answer on the flex list, as
>it seems that everything that you want to do doesn't require bison at all.
>
>--
>I'm alfonso e. urdaneta, and I approve this message.
>
>
>_______________________________________________
>address@hidden http://lists.gnu.org/mailman/listinfo/help-bison


  Hans Aberg






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