EOPL 3.9 and 3.10

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mitchel...@gmail.com

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Oct 25, 2013, 7:20:55 AM10/25/13
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I  have started working on 3.9 and 3.10.  Both require that you implement list operations within the LET language.

My thinking was that we had to create  a separate grammar for lists, but then indicate that a list was a kind of expression.

However, I keep on getting the following kinds of errors:
parser-generation: grammar not LL(1): shift conflict detected for class "(" in nonterminal expression:
(("(") (string "(") (non-term expression) (non-term expression) (string ")") (reduce call-exp))
(("(") (string "(") (non-term list) (string ")") (reduce list-exp))


Simply the following three lines will generate this error:

 (list () empty-list )
 (list (number list) list-list )
 (expression ("(" list ")" ) list-exp)


What am I doing/thinking wrong?

Thanks
Mitchell




Marco Morazan

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Oct 25, 2013, 9:18:22 PM10/25/13
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Start by defining a new expressed value(s) for lists. Don't confuse the specification for list values in the LET language with the specification of the LET language itself. After you have expanded the set of expressed values work on expanding the set of expressions.

Marco


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Cheers,

Marco

Have a´¨)
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