[antlr-interest] Lexer rules and unreachable alternatives (trying to understand lexer)

[Wincent Colaiuta]

Given a lexer with a single rule:

	OTHER : .+ ;

Why would ANTLR issue this warning?

	warning(201): T.g:8:9: The following alternatives are unreachable: 1

The warning goes away if I instead write:

	OTHER : .* ;

Looking at the syntax diagram in ANTLRWorks I see something like this:

	 /-------------------------\
	v                           |
OTHER -------> '\u0000'..'\uFFFE' ---===>

The final part of the rightmost arrow is highlighted in red.

If I write the rule like this, the warning goes away:

	OTHER : '\u0000'..'\uFFFE'+ ;

What am I misunderstanding here?

Cheers,
Wincent