XML News from Tuesday, February 21, 2006

The W3C XML Schema Working Group has posted the last call working draft of XML Schema 1.1 Part 2: Datatypes.

• "0000" is a legal year and values with negative years map onto the timeline such that "the year 0000 is 1 B.C.E., the year –0001 is 2 B.C.E., etc."
• Distinction between identity and equality; for instance positive and negative zero would be equal but not identical. Think of the difference between == and equals() in Java.
• New yearMonthDuration and dayTimeDuration types
• A precisionDecimal type that "retains information about the precision of the value. This type is aligned with the floating-point decimal types which will be part of the next edition of IEEE 754."
• An anyAtomicType data type
• Negative and positive zero are distinct, in conformance with IEEE 754

Changes since the last working draft are quite techical, and mostly involve validation rules. However no new types appear to have been added or removed.