predicateObjectList rule requires lookahead from Gregg Kellogg on 2011-12-15 (public-rdf-comments@w3.org from December 2011)

From: Gregg Kellogg <gregg@kellogg-assoc.com>
Date: Thu, 15 Dec 2011 10:08:55 -0500
To: "public-rdf-comments@w3.org" <public-rdf-comments@w3.org>
CC: Gavin Carothers <gavin@carothers.name>
Message-ID: <2850AAF0-9E14-46F3-BA43-3AAD5222296A@greggkellogg.net>

I believe that grammar rule [7] predicateObjectList [1] is not LL(1) and requires look ahead to know what branch to go into. For example:

[ :a :b ; ]

may  cause it to go down the ( ":" verb objectList )* branch instead of the ";"? branch, and result in an error. The previous definition did work okay:

[7] predicateObjectList ::= verb objectList ( ";" ( verb objectList)? )* 

Any reason it was changed?

Gregg

[1] http://dvcs.w3.org/hg/rdf/raw-file/default/rdf-turtle/index.html#sec-grammar

Received on Thursday, 15 December 2011 15:09:48 UTC