From: Peter Kirk (peterkirk@qaya.org)
Date: Wed Apr 28 2004 - 16:15:28 EDT
On 28/04/2004 11:58, Kenneth Whistler wrote:
>Peter Kirk continued:
>
>
>
>>>The PUA is intended for the internal use of applications (or groups of
>>>applications), or for interchange between applications by private
>>>agreement of all parties involved. ...
>>>
>>>
>>>
>>This is not quite right. From TUS section 15.7,
>>http://www.unicode.org/versions/Unicode4.0.0/ch15.pdf:
>>
>>
>>
>>>Private-use characters are assigned Unicode code points whose
>>>interpretation is not specified by this standard and whose use may be
>>>determined by private agreement among cooperating users.
>>>
>>>
>>Note the last word. The private agreement is not supposed to be between
>>all parties, including software developers. It is supposed to be between
>>*users*.
>>
>>
>
>"Users" is best understood here as Rich has indicated. It means
>"users of the standard". It does not mean "end-users of any software
>which is implemented with Unicode as the basis for its character
>handling".
>
>
In that case, the text of the standard needs to be amended to remove
this ambiguity. But as this amendment would in effect have the
consequence of making the PUA useless for any kind of data interchange
(and what is not data interchange is outside the scope of Unicode), I
would strongly oppose any such change. If you want to abolish the PUA,
have the courage of your convictions and propose doing so (or at least
formally deprecating it), instead of leaving it in the standard in a
form which makes it look useful but in fact be useless.
>...
>
>>Software developers, or applications, are not supposed to be party to
>>the agreement between *users*. While applications are of course not
>>obliged to support the PUA, if they choose to do so there should be no
>>expectation that they are party to any agreement. And so a group of
>>users with a private agreement can reasonably assume that software which
>>supports the PUA in general supports their particular agreement.
>>
>>
>
>Your last statement is non sequitur, and wrong besides.
>
>
Perhaps my point was not clear. But my understanding was that software
which claimed to support the PUA should allow display and basic
processing of PUA characters, according to their default properties if
there is no built-in support for specifying other properties. Display
would of course be based on the glyphs provided in the selected font.
This is how some applications in fact work, including Mozilla (on
Windows) which I am using at the moment. And so it is reasonable to
expect software like Mozilla to provide basic support e.g. for Ewellic
even though the Mozilla developers may never have heard of Ewellic. I
thought that was the point of the PUA. If in fact I am wrong and this is
not the point of the PUA, this needs to be clarified in the standard, as
at least I and the Mozilla developers seem to have been misled on this!
>A group of users with a private agreement *cannot* reasonably
>assume that software which supports the PUA in general supports
>their particular agreement. They have to investigate what the
>capabilities of that software, to see what it might or might
>not support in the way of particular behavioral extensions
>implied by your private agreement. And in most cases, you
>would either have to add on behavior yourself or pay someone
>else to do it for you. ...
>
Which comes back to my billions of dollars. Well, maybe only millions if
something can be hacked into an existing OS.
>... That is the risk and drawback of expecting
>to use PUA code points.
>
>--Ken
>
>
>
>
>
>
-- Peter Kirk peter@qaya.org (personal) peterkirk@qaya.org (work) http://www.qaya.org/
This archive was generated by hypermail 2.1.5 : Wed Apr 28 2004 - 16:59:16 EDT