Why do you want the SEMI in your AST? Jim
> -----Original Message----- > From: antlr-interest-boun...@antlr.org [mailto:antlr-interest- > boun...@antlr.org] On Behalf Of David Smith > Sent: Tuesday, June 07, 2011 4:41 AM > To: antlr-interest@antlr.org > Subject: [antlr-interest] AST with optional parameters > > I'm parsing a grammar in which the semicolon on the end of a line is > optional. So two of the statement rules might be: > | (ID GETS expr SEMI) => ID GETS expr SEMI -> ^(GETS ID expr > SEMI) > | (ID GETS) => ID GETS expr -> ^(GETS ID expr) > Since this occurs with a number of different assignment statements, I > would really like to collapse this into one rule that looks something > like this: > | (ID GETS) => ID GETS e=expr (s=SEMI)? -> ^(GETS ID $e $s) > but every implementation I can think of either refuses to generate the > grammar or, as in the case above, generates the grammar but decides > that the variable 's' is unknown. > Is there a any way to achieve this? > > DMS > > David M. Smith http://www.cc.gatech.edu/fac/David.Smith > Georgia Institute of Technology, College of Computing Sent from my ASR- > 33 Teletype > > > List: http://www.antlr.org/mailman/listinfo/antlr-interest > Unsubscribe: http://www.antlr.org/mailman/options/antlr-interest/your- > email-address List: http://www.antlr.org/mailman/listinfo/antlr-interest Unsubscribe: http://www.antlr.org/mailman/options/antlr-interest/your-email-address -- You received this message because you are subscribed to the Google Groups "il-antlr-interest" group. To post to this group, send email to il-antlr-inter...@googlegroups.com. To unsubscribe from this group, send email to il-antlr-interest+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/il-antlr-interest?hl=en.
