[antlr-interest] Re: Error return from lexer/parser

antlrlist antlrlist at yahoo.com
Tue Jun 17 09:50:13 PDT 2003


Sorry, I don't understand.

You say that your parser/lexer fails, but it does not rise any 
exception nor print any error message. Then how do you know it fails?
Don't take me wrong, I'm not joking. If no errors are detected, then 
this means that the entry is valid.

Things you could try:

 - Make sure that your defaultErrorHandler 
(http://www.antlr.org/doc/options.html#defaultErrorHandler) option is 
set to true.
 - Make sure that your grammar is not really rising exceptions (maybe 
you forgot a try/catch block that is catching them, or you erased it 
and forgot to re-compile?)
 - Make sure that your grammar can not accept the entry that you 
think is "wrong" (maybe your rules are not well defined, so they can 
accept more entries than the ones you thought about initially)
 - Finally, if nothing works, re-compile your analyzers with the -
trace command line option and trace the analysis.

I hope I could help you,

Enrique

--- In antlr-interest at yahoogroups.com, "Anil Kumar" <anilk at s...> 
wrote:
> Hi everyone,
> I have a simple grammar, which has description for expression. When 
i give
> it to the lexer/parser wrong expr. to the application, the 
lexer/parser
> fails but it does not raises exceptions nor does it returns any 
error
> status. Is there something missing that i have to specify to raise
> exception/return errors to the invoker of lexer/parser.
> Thanks,
> Anil
> 
> 
> DISCLAIMER: This email is bound by the terms and conditions 
described at 
> http://www.subexgroup.com/mail-disclaimer.htm


 

Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ 




More information about the antlr-interest mailing list