[antlr-interest] a left recursive walker rule

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Hi,
I have a rule in tree walker, which is left recursive:  A : (A|B)+ C ,

so I am trying to eliminate it 

A : (A|B)+ C
=> A : ( A(A|B)* | B(A|B)*) C
=> A : A(A|B)* C | B(A|B)* C
=> A : B(A|B)* C  ((A|B)* C)*
=> A : B ( (A|B)* C )+
=> A : B ( ( B((A|B)* C)+ |B )* C )+ //replace A with " B ( (A|B)* C )+ "
=> A : B( ( B [((A|B)* C)+ | ]* C)+ // need to replace A with " B ( (A|B)* C )+ " again
=> A : ... //then again and again forever, never ends

Any better solution?

Thanks

Jigang





		
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