Could someone please explain to me why recursive-descent parsers can't work with a grammar containing left recursion?
2 Answers
32
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20
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For whoever is interested
A ::= A B | A C | D | E
can be rewritten as:
A ::= (D | E) (B | C)*
The general form of the transformation is: any one of the non left recursive disjuncts followed by any number of the left recursive disjuncts without the first element.
Reforming the action code is a bit trickery but I thing that can be plug-n-chug as well.