Cart
|
[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message] Re: W3C Schema: Resistance is Futile, says Don Box
 Michael Kay wrote: > So what's the accurate value, remembering that XML Schema and ISO 8601 > both use a proleptic Gregorian calendar, and that the ISO 8601 calendar > includes a year 0 while the XML Schema version does not? Your reminders above are useful for one who chooses to employ a gDate process for instantiating a date from the attribute value "-43-03-13". I see other infelicities with using that particular form of markup if the instance is to be processed by widely useful general purpose tools, but that is not the primary issue here. The element content itself (the ides of March, 710 A.U.C.) if instantiated as a date by an accurate application of the AUC process as redefined by Caesar himself must yield a result of the fifteenth day of the third month of the 710th year. That is the point of units as a component of the lexical content which is to be instantiated with some particular semantics. If the units are to be given the semantic expression generally expected, then those semantics will be elaborated through an algorithmic process--a reckoning--which yields semantics predicated on the chosen units. Converting inches to centimeters with a coefficient of 2.54 is such a process. Performing the resolution of an AUC date as prescribed by Caesar is another. Resolving a date from lexical content by the operation of a gDate algorithm is a different process. My original point with John is that a date which claims to carry the semantics of AUC units should resolve to the result which the AUC process, as defined, yields from the given lexical input. The AUC resolution algorithm is a definition of process, not of nominal identity, just as is the definition of inches in terms of centimeters. The deeper point is that the element content, and separately the attribute value, in this instance are merely syntactic constructs as given. Resolved as a date on one simple reading of its own terms (i.e., AUC) the element content yields a result which is unquestionably the 15th of March. Resolved as a date through the execution of a gDate process the attribute value yields the 13th. The markup, as given, might be reasonably interpreted (an elaboration of specific semantics through process) to assert that these dates are the same. From a third party point of view (John's time travel argument) they can be so understood. But on the particular terms of each process, there are separate and different results. A process which yields any other date than the 15th in this instance cannot legitimately be considered an AUC process, or more exactly a process elaborating AUC semantics. The element content includes AUC units. We cannot claim to instantiate that content on those units if we reach any other result than the 15th. I apologize if this seems like nitpicking or if my point appears nearly invisible. It is not. Redoing two centuries of scholarship in philology (and reversing the implicit semantic understandings of twenty previous centuries) has amply demonstrated that a carefully articulated progress from the lexical to the objectified is necessary once we understand the difference between a text and its instantiated semantic elaborations. I am pushing as best I can to get the practice of XML to that point as completely and swiftly as possible. I try not to be too pushy about it, and will not take it amiss if I am told to slow down or to revisit arguments, but I know where I am going and I intend to get there with, I hope, as great a number as can be persuaded that this is a worthwhile exercise. Respectfully, Walter Perry 
|
PURCHASE STYLUS STUDIO ONLINE TODAY!Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced! 
Download The World's Best XML IDE!Accelerate XML development with our award-winning XML IDE - Download a free trial today! Subscribe in XML format
|
|||||||||
