Re: Unassigned code points discussion in draft-hoffman-stringprep-07.txt

At 4:52 AM +0100 12/6/02, Simon Josefsson wrote:
>A step for handling unassigned code points would make it clearer:
>
>5) Check unassigned code points -- Possibly check the output for
>    unassigned code points, according to the profile.  This is
>    described in section 7.
>
>A comment on whether this is what was intended or not would be
>appreciated.

You can do it last, you can do it first, or you can check for 
unassigned code points during the prohibit step. It will work the 
same regardless of when you check. The mapping, normalization, and 
bidi steps will never add any unassigned characters, so checking for 
them in any step has the same effect.

>It could be argued that step 3 covers for unassigned code points, but
>prohibited characters and unassigned characters are treated separately
>elsewhere, and the forward reference does not include section 7.  So
>unless it is stated explicitly that case 3 covers for unassigned code
>points too, one will not likely reach that conclusion when reading the
>document.

Given the length of section 7, and the many forward references to it, 
it seems like that it would be noticed. If we revised the document, 
we could add explicit text saying you can do the check whenever you 
want.

--Paul Hoffman, Director
--Internet Mail Consortium