That's what I have now. It does work. I was just hoping to differentiate it in my tree grammar so I wanted "NAME" to have a different token.
-----Original Message----- From: John B. Brodie [mailto:[email protected]] Sent: Tuesday, August 23, 2011 3:58 PM To: Scott Smith Cc: [email protected] Subject: Re: [antlr-interest] Lexer question try rule1: IDENTIFIER ':' expression ; that is why bother differentiating the two tokens? On Tue, 2011-08-23 at 21:19 +0000, Scott Smith wrote: > I have a parser that is doing pretty much what I want. However, I want to do > the following. > > I have a definition for an IDENTIFIER > > IDENTIFIER: LETTER (LETTER | NUMBER) // LETTER and NUMBER mean > the usual thing > > Now in some of my rules, I'm looking for an IDENTIFIER and in one of my rules > I look for a NAME. NAME has exactly the same definition as IDENTIFIER > (starts with a letter followed by alphanumerics). However, you can tell by > the token after whether it was a NAME or an IDENTIFIER. To be more explicit, > a NAME is ALWAYS followed by a colon. An IDENTIFIER can be followed by a > number of things, but NEVER by a colon. > > So, I have rules that looksomething like: > > rule1: > NAME ':' expression > ; > > rule2: > IDENTIFIER '+' expression > | IDENTIFIER '-' expression > ; > > I don't seem to be able to make this work. Can someone suggest a solution? > Do I have to turn on backtracking to make this work? > 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 [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/il-antlr-interest?hl=en.
