RE: Reuse issue in DISelect

You can place your conditional calculations in a custom XPath function and merely return Booleans to the DISelect page. If your calculations need to change, just update the XPath function implementation, and all your pages will now be using the new calculations.

Similarly, things like group membership can be dealt with externally.

The point, however, from a standardisation position is that external custom methods will reduce the portability of both the pages and the skills of the developer. So, if/when new properties or concepts (e.g. grouping) are proposed within a standardisation process, this should include the definition of common methods/functions and their binding in expressions such as those used in DISelect.

But of course you already know that. I'm just noting it here for the benefit of others who read this list. The DDWG will hopefully be working on a more comprehensive set of properties/methods and I expect these will be considered by DIWG, and we will see these advances coupled to DISelect in some way.

---Rotan.

-----Original Message-----
From: www-di-request@w3.org [mailto:www-di-request@w3.org] On Behalf Of José Manuel Cantera Fonseca
Sent: 19 October 2006 10:27
To: www-di@w3.org
Subject: Reuse issue in DISelect


Dear all,

Another thread for another question. I'm envisaging the following issue with DISelect and has to do with the reuse of conditions.

Imagine I'm a developer and bacause of the requirements of my application I have to put the same selection conditions in several authoring units. During the lifetime of the project I realize that those conditions, that are spread over all the authoring units, are not accurate. So, to fix it, I will have to edit all the authoring units and change in all places my conditions.

Does DISelect have condition-reuse mechanisms that allow a developer to avoid this issue?

With respect to those conditions that only has to do with the delivery context subset composed by device properties (those found in the DDR), Wouldn't it better that the developer could define (externally) groups of devices, by means of logical conditions of belonging, and reference those groups logically in the select expressions within the authoring units?

If due to some reason the conditions change I will only have to change them in one place, outside the authoring units, that probably will be developed by designers with no deed knowledge of device specific technologies.

Thanks and best regards

Received on Thursday, 19 October 2006 10:45:48 UTC