On Friday, Sep 19, 2003, at 16:56 US/Pacific, Hal Helms wrote: > The problem you're running into is why we so urgently need for CF to > have the concept of "null" - a symbol that fulfills the contract for > any > class.
Actually I think Jim's problem is one of modeling: he has "Venue" but really that is modeling two things... a physical location (e.g., "Boston Common") and the actual performance rooms within it (e.g., "Frog Pond", "Brewer's Fountain" etc). If you separate out these two concepts as Venue and PerformanceRoom then a Venue always has at least one PerformanceRoom. Both entities have their own useful properties: a Venue has various facilities, a PerformanceRoom has seating / standing capacities etc. Yes, there are some cases where a genuine null would be a big help (and I've requested it too) but by examining the multiplicity in OO relationships you can usually workaround it in a fairly clean way. The hardest thing to work around is "0 or 1" for which you pretty much have to use isDefined() or structKeyExists()... Sean A Corfield -- http://www.corfield.org/blog/ "If you're not annoying somebody, you're not really alive." -- Margaret Atwood ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Message: http://www.houseoffusion.com/lists.cfm?link=i:4:137784 Archives: http://www.houseoffusion.com/lists.cfm?link=t:4 Subscription: http://www.houseoffusion.com/lists.cfm?link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 This list and all House of Fusion resources hosted by CFHosting.com. The place for dependable ColdFusion Hosting. http://www.cfhosting.com
