Questions about optional and abset

• From: Peter Canning <canning@vitria.com>
• Date: Tue, 02 May 2000 20:31:45 -0700
• To: www-xml-schema-comments@w3.org
• Message-Id: <4.2.2.20000502202128.00ab9300@icarus.vitria.com>

The structure specification identifies some schema component properties 
(e.g. the "min occurs" property in the "Attribute Declaration" component) 
as optional and states (section 3 paragraph 1) that optional properties 
that are missing have "absent" as their value.  It also describes some 
properties (e.g. the "target namespace" property in the "Attribute 
Declaration" component) as mandatory, but includes "absent" in the list of 
legal values.

What is the difference between an optional property, and a mandatory 
property whose value can be "absent"?

	thanks,
	Peter Canning

Received on Tuesday, 2 May 2000 23:31:46 UTC