Fw: [F&O] IBM-FO-108: Normative definition of case mapping


     From the minutes of the 2004-03-16 minutes of the joint telecon on 
F&O issues [1]:
5. Normative description of case mapping
ACTION HZ will propose.
ACTION MHK reply to Igor Herscht.

     The problem that we were trying to point out in qt-2004Feb0979-01 [2] 
was that the first entry in the table in Section 1.2 of Unicode TR#21 [3] 
states, in part, "Only legacy implementations that cannot handle case 
mappings that increase string lengths use UnicodeData case mappings 
alone."  The penultimate paragraph of that section states, in part, "The 
full case mappings for Unicode characters are obtained by using the 
mappings from SpecialCasing plus the mappings from UnicodeData, excluding 
any latter mappings that would conflict."

     Similarly, the first paragraph of Section 2.3 of TR#21 [4] reads as 

The following specify the default case conversion operations for Unicode 
strings, in the absence of tailoring. In each instance, there are two 
variants: simple case conversion and full case conversion. In the full 
case conversion, the context-dependent mappings mentioned above must be 

     All this seems to admit of (at least) two possible case mappings.  We 
believe that full case conversion was intended.

     I propose that in the first paragraph of each of Section 7.4.7 of 
F&O, we change "The precise mapping is determined using [Unicode Case 
Mappings]," to read "The precise mapping is the full case mapping variant 
of the toUpperCase operation defined in [Unicode Case Mappings],"  with an 
analogous change to 7.4.8.


[2] http://lists.w3.org/Archives/Member/w3c-xsl-query/2004Mar/0096.html
[4] http://www.unicode.org/reports/tr21/tr21-5.html#Data
Henry Zongaro      Xalan development
IBM SWS Toronto Lab   T/L 969-6044;  Phone +1 905 413-6044

Received on Tuesday, 23 March 2004 10:03:30 UTC