No, there were in fact round-trip mappings defined (and used)
at the time. See, e.g.:
http://www.unicode.org/Public/MAPPINGS/OBSOLETE/EASTASIA/KSC/OLD5601.TXT
which shows the Unicode 1.1 <--> KS C 5601-1987 mappings for
the old range of Unicode 1.1 Hangul syllables 3400..3D2D.
http://www.unicode.org/Public/MAPPINGS/OBSOLETE/EASTASIA/KSC/KSC5601.TXT
shows the updated mappings for the complete johab set for Unicode 2.0
to an EUC encoding of KS C 5601-1992.
I'm not sure about the details of the implementation of KS C 5657-1991.
Somebody more familiar with the churn in Korean standards from
the early 1990's might know, however.
--Ken
On 6/24/2015 1:03 PM, Karl Williamson wrote:
On 06/19/2015 04:12 PM, Ken Whistler wrote:
The Unicode 2.0 set of 11,172 was known as the "Johab" set from KS C
5601-1992.
That was an algorithmically designed replacement of the earlier sets
from
Korean standards -- designed to cover all modern syllables
algorithmically,
by putting all the combinations of initial, medial and final jamos in a
defined
alphabetical order, whether or not each syllable that resulted was
actually
attested in modern Korean use or not.
Does this mean the original 2 standards (KS C 5601-1987 and KS C
5657-1991) fell into disuse (or perhaps never were actually used) so
there was no need to map the new code points to them (hence no
round-trip defined)?
