[antlr-interest] RE Lexer rule for number range matching ?

[Gavin Lambert]

At 05:52 25/04/2008, Nagesh, Harsha wrote:
 >
 >I tried these suggestions, but I am getting the following 
warning
 >in ANTLRWorks when I include this rule
 >
 >"The following token definitions are unreachable:.."

You've probably got another lexer rule that matches sequences of 
digits.  Remember, the lexer is contextless, so if you have other 
possibilities for digit groups you can't do the range-checking in 
the lexer.  You need to make a general-purpose NUMBER rule in the 
lexer and do your range checking in the parser instead.