Re: LL(1) parser table

SLK Parsing <dr_feriozi@prodigy.net>
13 Jan 2002 22:54:07 -0500

          From comp.compilers
Related articles
LL(1) parser table hyperarien@yahoo.com (2002-01-05)
Re: LL(1) parser table gsc@zip.com.au (Sean Case) (2002-01-07)
Re: LL(1) parser table dr_feriozi@prodigy.net (SLK Parsing) (2002-01-13)
Re: LL(1) parser table kaarthik@cisco.com (Kaarthik) (2002-01-13)
Re: LL(1) parser table kaarthik@cisco.com (Kaarthik) (2002-01-13)
Re: LL(1) parser table hyperarien@yahoo.com (2002-01-14)
| List of all articles for this month |
From: SLK Parsing <dr_feriozi@prodigy.net>
Newsgroups: comp.compilers
Date: 13 Jan 2002 22:54:07 -0500
Organization: Prodigy Internet http://www.prodigy.com
References: 02-01-026
Keywords: parse, LL(1)
Posted-Date: 13 Jan 2002 22:54:07 EST

lee wrote:
>
> S -> E
> E -> TE'
> E'-> -TE'
> E'-> epsilon
> T -> FT'
> T'-> /FT'
> T'-> epsilon
> F -> GF'
> F'-> ++F'
> F'-> epsilon
> G -> ++E
> G -> id
>
> Still after all this grammar is ambiguous. Because F' FOLLOW set is
> {/,-,++,$} and there are two entries for [F',++] comination.
>
> Does this means the above grammar is not suitable for LL1 parsing?
>


It just means that you made a mistake in the grammar. It should be


G -> ++G


assuming the precedence order that is implied by the grammar. Or if you
want low precedence for prefix ++ then use


E -> ++_* T E'
++_* -> ++ ++_*
++_* -> epsilon


instead of


E -> TE'
G -> ++E

Post a followup to this message

Return to the comp.compilers page.
Search the comp.compilers archives again.