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properties (w</title></head><body>
<div>At 6:59 PM -0700 4/30/08, Mark Davis wrote:</div>
<blockquote type="cite" cite><i>A. First test for unassigned:</i><br>
</blockquote>
<blockquote type="cite" cite>gc=Cn => UNASSIGNED<br>
(default ignorable & gc!=Cn) => DISALLOWED<br>
</blockquote>
<blockquote type="cite" cite><br>
Advantage: it means that Unicode unassigned = UNASSIGNED, which is
conceptually simpler for people. Functionally, this works, because
noncharacters will never change from UNASSIGNED and thus never be
allowed in labels, and unassigned default ignorable characters will
become DISALLOWED as soon as they are assigned.<br>
<br>
<br>
<i>B. First test for noncharacters, then unassigned</i><br>
</blockquote>
<blockquote type="cite" cite>noncharacters => DISALLOWED<br>
(default ignorable & gc!=Cn) => DISALLOWED<br>
(gc=Cn - noncharacters) => UNASSIGNED<br>
</blockquote>
<blockquote type="cite" cite><br>
Advantage: we know that noncharacters will never be PVALID so we might
as well indicate that.<br>
<br>
<br>
<i>C. First test for noncharacters and default ignorable, then for
unassigned</i><br>
</blockquote>
<blockquote type="cite" cite>noncharacters => DISALLOWED<br>
(default ignorable) => DISALLOWED<br>
(gc=Cn - noncharacters - default_ignorable) => UNASSIGNED<br>
</blockquote>
<blockquote type="cite" cite><br>
Advantage: we know that noncharacters and default ignorables will
never be PVALID so we might as well indicate that.<br>
</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>I actually don't care to much which of
these options we choose - functionally it doesn't make a difference.
Here I'm just trying to present a clearer picture of the
situation.</blockquote>
<div><br></div>
<div>My preference is A because it is conceptually simpler.</div>
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