[antlr-interest] token definitions can never be matched because prior tokens match the same input
Ilya Sterin
sterini at gmail.com
Fri Nov 28 15:05:58 PST 2008
Based on the grammar you provided it doesn't seem you've defined it
correctly. First, I'd define some of your patterns as lexer tokens.
Try this...
r0 : 'OK' R1 R2? R3?
;
R1 : 'V'
| 'W'
;
R2 : (APHA_OR_DIGIT)(APHA_OR_DIGIT)
;
R3 : (APHA_OR_DIGIT)(APHA_OR_DIGIT)(APHA_OR_DIGIT)
;
fragment
APHA_OR_DIGIT : ALPHA_UC | DIGIT;
fragment
ALPHA_UC : 'A'..'Z'
;
fragment
DIGIT : '0'..'9'
;
On Thu, Nov 27, 2008 at 3:25 AM, matt.jazz <matt.jazz at laposte.net> wrote:
>
> Hello,
>
> I'm new to ANTLR and i need to create a translator. I encounter a problem
> with the following grammar.
>
> Grammar :
>
> r0 : 'OK' r1 r2? r3?
> ;
>
> r1 : 'V'
> | 'W'
> ;
>
> r2 : ('A'..'Z''0..9')('A'..'Z''0..9')('A'..'Z''0..9')
> ;
>
> r3 : ('A'..'Z''0..9')('A'..'Z''0..9')
> ;
>
> Examples of valid sentences :
>
> OK W 65 0X9
> OK V AZ 78F
>
> Error :
>
> The following token definitions can never be matched because prior tokens
> match the same input
>
> Thanks for your help
>
> Matt
>
>
>
> Créez votre adresse électronique prenom.nom at laposte.net
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