presto-main/src/main/java/io/prestosql/operator/scalar/JoniRegexpCasts.java/JoniRegexpCasts/castVarcharToJoniRegexp
class JoniRegexpCasts:    @LiteralParameters("x")
    @ScalarOperator(OperatorType.CAST)
    @SqlType(JoniRegexpType.NAME)
    public static Regex castVarcharToJoniRegexp(@SqlType("varchar(x)") Slice pattern)
    {
        return joniRegexp(pattern);
    }