Thanks for the response. I already am using an exclusive start condition to pass the comment to Bison. Could you explain what you mean? I don't see how this can solve the problem of ignoring a token if it doesn't fit into a rule.
John P. Hartmann wrote: > > That is probably much easier to handle by exclusive start conditions > in the scanner. > > On 23 July 2011 02:40, uclacasey <[email protected]> wrote: >> >> I'm writing a program that handles comments as well as a few other >> things. If >> a comment is in a specific place, then my program does something. >> >> Flex passes a token upon finding a comment, and Bison then looks to see >> if >> that token fits into a particular rule. If it does, then it takes an >> action >> associated with that rule. >> >> Here's the thing: the input I'm receiving might actually have comments in >> the wrong places. In this case, I just want to ignore the comment rather >> than flagging an error. >> >> My question: >> How can I use a token if it fits into a rule, but ignore it if it >> doesn't? >> Can I make a token "optional"? >> >> (Note: The only way I can think of of doing this right now is scattering >> the >> comment token in every possible place in every possible rule. There MUST >> be >> a better solution than this. Maybe some rule involving the root?) >> -- >> View this message in context: >> http://old.nabble.com/How-to-ignore-a-token-if-it-doesn%27t-fit-in-with-a-rule--tp32119417p32119417.html >> Sent from the Gnu - Bison - Help mailing list archive at Nabble.com. >> >> >> _______________________________________________ >> [email protected] https://lists.gnu.org/mailman/listinfo/help-bison >> > > _______________________________________________ > [email protected] https://lists.gnu.org/mailman/listinfo/help-bison > > -- View this message in context: http://old.nabble.com/How-to-ignore-a-token-if-it-doesn%27t-fit-in-with-a-rule--tp32119417p32120789.html Sent from the Gnu - Bison - Help mailing list archive at Nabble.com. _______________________________________________ [email protected] https://lists.gnu.org/mailman/listinfo/help-bison
