[antlr-interest] Do lexer rules have scopes?

[Gavin Lambert]

At 07:36 12/02/2008, Matt Benson wrote:
 >
 >When attempting to generate:
[...]
 >fragment
 >DollarBrace
 >scope {
 >	int depth;
 >}
 >	:	'${' {$DollarBrace::depth++;}
 >		(DollarBrace|.)*
 >		'}' {$DollarBrace::depth--;}
 >	;
 >
 >
 >I get:
 >
 >[12:33:17] error(10):  internal error: /tmp/wip.g3 :
 >java.lang.NullPointerException
 >org.antlr.tool.DefineGrammarItemsWalker.ruleScopeSpec(DefineGrammar
 >ItemsWalker.java:964)

I don't believe lexer rules support scopes, no.  You can use 
member variables, though, as long as you're careful.