ANTLR lexing getting confused over '...' and floats

Posted by Andy Hull on Stack Overflow See other posts from Stack Overflow or by Andy Hull
Published on 2010-04-20T19:13:37Z Indexed on 2010/04/20 19:23 UTC
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I think the ANTLR lexer is treating my attempt at a range expression "1...3" as a float. The expression "x={1..3}" is coming out of the lexer as "x={.3}" when I used the following token definitions:

FLOAT : ('0'..'9')+ ('.' '0'..'9'+)? EXPONENT? | ('.' '0'..'9')+ EXPONENT? ;

AUTO : '...';

When I change FLOAT to just check for integers, as so:

FLOAT : ('0'..'9')+;

then the expression "x={1...3}" is tokenized correctly. Can anyone help me to fix this?

Thanks!

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