ExpressionParser { static Parser<Expression> notExists(Parser<Relation> relation) { return phrase("not exists").next(relation) .map(e -> new UnaryRelationalExpression(e, Op.NOT_EXISTS)); }    }
@Test public void testNotExists() { TerminalParserTest.assertParser(ExpressionParser.notExists(RelationParser.TABLE), "not exists t", new UnaryRelationalExpression(table("t"), Op.NOT_EXISTS)); }