[pdftex] OT: Unicode and typesetting

Michael Chapman chapman at mchapman.com
Fri Apr 8 13:47:06 CEST 2005

Dear Jim,

	Thanks for your reply and comment.

On Friday 08 April 2005 12:38 am, you wrote:
> The reason most of those odd/extra characters exist is due to Unicode/
> iso10646's other major raison d'etre:  conversion to/from and between
> legacy encodings.
Thanks, I see the need to be able to convert from 'old' encodings to Unicode 
(life would indeed be difficult without it).

> Were it not for that requirement quite a few more unifications could
> have occurred.

But, even for conversions, why could not the Angstrom symbol in one old 
encoding map to the sample codepoint as the A-with-circle-above does from 
another encoding?
And, if they cannot, why cannot one of the points be a 'symbolic link' to the 
other (i.e. "you can render either code point with any (sensible) glyph you 
like, but you must render the two codepoints with exactly the same glyph')?

(One could argue differently I suppose for conversion _from_ Unicode, but 
that is such a can of worms. It is, I am sure worsened, if you can only 
convert the A-with-circle-above to some Nordic encoding, but not the Angstrom 
symbol --who knows which the document creator (human or mechanical) might 
have used?)

I suppose my (thusfar) unspoken problem is that I cannot understand the 
logic. If I am wrong I would like to understand. What I fear, though, is that 
Unicodes's foundations are not as firm as they ought to be .... which will 
inevitably mean more changes in the years to come ....



P.S. I claim no better overview, but in trying to archive material 
electronically each day I wrestle with trying to decide what is/are:
mark up: <ol> ... <li> ....</li>
codepoints: '(g)' [if it existed!]
glyph(s): '(' 'g' ')'
and whether anyone will find the seventh item in x years time.

P.P.S. Would have replied 'off list' but your mail server is apparently 
<cloos at jhcloos.com>: host jfk.uu.jhcloos.net[] said: 554 Service
    unavailable; Client host [blocked using sbl-xbl.spamhaus.org;

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