[antlr-interest] Change type of current AST

[Gavin Lambert]

At 11:51 7/06/2008, Dimitrios Kolovos wrote:
 >I've found that the following works (in case anyone faces a
 >similar issue in the future):
 >
 >additiveExpression
 >	:	multiplicativeExpression (('+'^|'-'^) 
multiplicativeExpression
 >		{if (root_0.getToken() != null)
 >root_0.getToken().setType(Operator);})*
 >	;
 >
 >I'm sure there is a more elegant way but this will do for now...

How about this:

additiveExpression
   : multiplicativeExpression ((o='+'^|o='-'^) 
multiplicativeExpression
     { $o.setType(Operator); } )*
   ;

(You might need to rearrange the = and ^ a bit.)

Though I'm not entirely sure how either of these will react with 
backtracking.