L2/04-006

Subject:      Comments on many to one mappings
Date/Time:    Sat Dec 27 18:31:37 EST 2003
Contact:      ralf.hagen@unibw-muenchen.de

In http://www.cl.cam.ac.uk/~mgk25/unicode.html , Mr Kuhn points out
"many to one"-mappings; the relevant ones are:

=========================================================================
UCS characters	equivalent character	in target code

U+00B5 MICRO SIGN
U+03BC GREEK SMALL LETTER MU 	0xB5	ISO 8859-1

U+00C5 LATIN CAPITAL LETTER A WITH RING ABOVE
U+212B ANGSTROM SIGN 	0xC5	ISO 8859-1

U+03A9 GREEK CAPITAL LETTER OMEGA
U+2126 OHM SIGN 	0xEA	CP437

U+03B5 GREEK SMALL LETTER EPSILON
U+2208 ELEMENT OF 	0xEE	CP437
=========================================================================

(Contrary to Mr Kuhn, I do not place the small greek beta / german
sz-ligature (ß) into this list.)

Here, I see a major problem.

First, I see no reason for the distinction. Eg, no one would distinguish
between "capital latin N / Newton sign" or "small latin m / Meter sign".

Second, when UTF-characters get into Keymaps, I see the problem that if
I search for "100 &Ohm;", the visually identical characters are then
totally different. I might as well look for "Y" and search "Z".

Third, this is not mere theoretical rambling; there /are/ fonts including
greek and nordic characters, but not these "specials".

So, if those special characters were commonly used, this would in my
opinion lead to Chaos.

Please consider deprecating them.

Yours
Ralf Hagen