On 19 Aug 2001 10:00:49 -0500, Steve Spicklemire wrote:
Hi Folks,
On Sunday, August 19, 2001, at 01:06 AM, Michael R. Bernstein wrote:
If you want the retreival of meta-data without waking up the object, you still need to layer on the global unique id with ZCatalog on top of ZPatterns.
Hmm... one nice thing about ZPatterns is that you could control what is stored where, and when it's looked up, or "woken up" at the SkinScript level so the application doesn't have to muss with the details (and you can change your mind later about the details with no impact on the application!). This, to my way of thinking, is a huge advantage!
You're right, of course. I hadn't used ZPatterns in a while, and wasn't aware of the per transaction caching of data (which basically means that within a transaction an object only needs to be woken up once to get the neccessary data), but does ZPatterns currently have a built in way for doing persistent caching of meta-data? If not, then the easiest way to get this would be to layer the ZCatalog approach on top of ZPatterns, and using SkinScripts to hide the source of the referred object's info. SkinScripts do allow you to hide the implementation of all this caching, along with the storage details, from the application. This flexibility is very important for making it possible to re-deploy the application in new circumstances where your original assumptions for storage and caching are invalidated. In other words, ZPatterns is a framework building framework (a meta-framework) and seems to be best suited for building application frameworks that are flexible and future-proof, rather than building 'mere' applications. Cheers, Michael.