[antlr-interest] Multiple optional fields question

[mynetadm]

Hi list

I'm doing an parser to test de ANTLR capabilities and I have one
problem,,,, 

we have something like :

test+1200+234EM123+1+TEST;

where fields : test, 1200 , 234EM123 are mandatory and 1 and TEST are
optional. I have to support options like :

test+1200+234EM123++TEST; or test+1200+234EM123+1 or test+1200+234EM123;

so I made :

class myParser extends Parser;
options  { k=4; }
test:    ( field1:TEXT DELIM field2:NUMBER DELIM copositeField 
          (DELIM (field3:DIGIT)?)?
           (DELIM (field4:TEXT)?)?
           ENDLINE
          );
compositeField: (
                   na:NUMBER t:TEXT nb:NUMBER
                )
class myLexer extends Lexer;
DIGIT:  	('0'..'9');
NUMBER:		(DIGIT)(DIGIT)+;
CHAR:		('a'..'z' | 'A'..'Z');
TEXT:		(CHAR)(CHAR)+;
ENDLINE:         ";";


the problem is that :

test+1200+234EM123+1+TEST; interprets corectly
test+1200+234EM123+1;      interprets corectly
test+1200+234EM123++TEST;  interprets corectly
test+1200+234EM123;        gives me an unexpected end of line

Can anyone help me please?


BR,
alecs











 
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