Re: ANSI C grammar without shift-reduce conflict on 'ELSE'

> For the dangling else problem an appropriately transformed grammar is
> this:


> S: Matched
> | Unmatched
> ;
> Matched: if E then Matched else Matched
> | Other_S
> ;
> Unmatched: if E then S
> | if E then Matched else Unmatched
> ;


> A nice explanation of this construction can be found at
> <http://marvin.cs.uidaho.edu/~heckendo/CS445F07/danglingElse.html>.


But then the parser is (slightly) less efficient.
Wouldn't it be nice if yacc were able to generate the same parse table?


                Stefan
[If you tell yacc to use precedences to resolve the ELSE conflict, you
get a smaller parse table, but I would be astonished if there were any
real situations where the extra shift and reduce made a measurable
difference in compiler performance. -John]

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