presto-spi/src/main/java/io/prestosql/spi/predicate/Marker.java/Marker/toString
class Marker:    public String toString(ConnectorSession session)
    {
        StringBuilder buffer = new StringBuilder("{");
        buffer.append("type=").append(type);
        buffer.append(", value=");
        if (isLowerUnbounded()) {
            buffer.append("<min>");
        }
        else if (isUpperUnbounded()) {
            buffer.append("<max>");
        }
        else {
            buffer.append(getPrintableValue(session));
        }
        buffer.append(", bound=").append(bound);
        buffer.append("}");
        return buffer.toString();
    }