Re: converting this grammar to LL1

"Joachim Durchholz" <joachim_d@gmx.de>
24 Oct 2002 23:57:45 -0400

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From: "Joachim Durchholz" <joachim_d@gmx.de>
Newsgroups: comp.compilers
Date: 24 Oct 2002 23:57:45 -0400
Organization: Compilers Central
References: 02-10-097
Keywords: parse, LL(1)
Posted-Date: 24 Oct 2002 23:57:45 EDT

Te-Cheng Shen wrote:
> Then the resulting grammar is
>
> E-> F = E
> E -> F
>
> F -> id| & id | ( E ) | E [ int ]


I think you'll have to factor out the e[int] alternative as well. How
the exact rules should be depends on how you want to parse E=E[int]: as
(E=E)[int] or as E=(E[int])?
IOW your grammar is ambiguous, and ambiguities make any grammar non-LL
(and also non-LR).


Regards,
Joachim
--
This is not an official statement from my employer.


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