ANTLR and LEX states

How do you rewrite/convert lex grammars that include states to ANTLR?
There is a simple example in the ANTLR documentation, but it is not
clear to me how to convert a grammar similar to the following.


This is a snippet from VCD parser from Maarten Ditzel.


%x text


%{
%}


s [[:space:]]


%%


<INITIAL>{s}+ { /* skip whitespace */ }


\$comment { BEGIN(text); return TK_COMMENT; }
\$version { BEGIN(text); return TK_VERSION; }


<text>\$end { BEGIN(INITIAL); return TK_END; }
<text>. { yylineno--; yymore(); }
<text>\n { yylineno--; yymore(); }
<text>./\$end { sval = yytext; return TK_TEXT; }
<text>\n/\$end { sval = yytext; return TK_TEXT; }


Basically I am trying to parse something like:


$comment
    any character here
    including CR/LF
$end


$version
    any character here
    including CR/LF
$end


There are a lot more states in this grammar, but it would be
appreciated if anyone has hints for converting this snippet of the
grammar.


Thanks,
-- Amal

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