"ref","name");
// recover by returning something that can be interpreted as Pattern
return Expression.nullSet;
}
TREXGrammar grammar = ((TREXBaseReader)this.reader).grammar;
if( parentRef ) {
grammar = grammar.getParentGrammar();
if( grammar==null ) {
reader.reportError( TREXBaseReader.ERR_NONEXISTENT_PARENT_GRAMMAR );
return Expression.nullSet;
// recover by returning something that can be interpreted as Pattern