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Donald> But TeX really is 8bit.
Donald>
Donald> What were you thinking of?

That the TeX3 8 bit extensions don't really work that well. A 7bit TeX
could pretend that there was basically only one encoding around: ASCII (as
extended to some keyboard once found in some university somewhere)
(or at least you knew which system you were on and your tex system could
use xchr translations if you were not using ASCII)

But 8bit encodings have never been even remotely like that.
A "natural" system designed for 8bit encodings would have some
sensible way of mapping different input encodings.

TeX does not, and so we get into the whole business of active characters
and inputenc. This basically works as specified but that does not mean
it always works as users expect, and it's a major complication within the
latex kernel to pass all these things round without it blowing up.

Similarly the difficulty of producing hyphenation tables that work with
different 8bit font encodings. (Not so much the perceived difficulty of
distributing such a thing, suitable macros could fix that, more the
impossibility of sharing the tables at tex's inner level)

TeX3 is really 8bit in the sense that all the restrictions to 127 became
restrictions to 255.

But a real 8bit system would have done more, just as omega isn't just a
matter of taking restrictions to 2^8 and making them 2^16 or 2^32 (even
if that was the first stage).

David

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