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Re: Line-by-line evaluation or all at once?
Dan Sandberg wrote:
> 1 - Being able to parse constructs in the grammar other than just the
> starting production.
This feature only works well with LL grammars. LR parsers maintain an
"ambiguous" state as long a possible. This is why LR parsers can deal
with grammars that LL parsers can't. So, to parse from a different
starting point, you need to generate new LR parsing tables. LL parsers
only allow an unambiguous parse context. So, they can start from any
state without problem.
> 2 - Having EOF be an explicit part of the grammar. It would be nice if
> you could go :
EOF is a special thing. I have plans about its handling in SableCC 3.0,
but probably not through explicit notation as a token in the grammar.
To give you an idea, (and as previously suggested on the mailing-list),
one can play with things like "0 lookahead" to end a parse, and not
reuire an "EOF" between multiple parses.
Etienne
--
----------------------------------------------------------------------
Etienne M. Gagnon, M.Sc. e-mail: egagnon@j-meg.com
Author of SableCC: http://www.sablecc.org/
and SableVM: http://www.sablevm.org/