Portability question

[Mike Shannon]

	Michael Baldwin in the cited article mentions that you can't
use an enumerated variable in expressions like
enumvar++
or
array[enumvar].

	I've noticed this too, and I wonder if there is any good reason
for restricting this use of enumerated types?  Or is it just a limitation
of the existing implementations? (which implies: "There are lots of compilers
out there which do not support this feature, therefore it can never
become part of the language.")
	If there is a good reason for disallowing this use of enumerated
variables, I'd like to hear it.
	Finally, if there is no good reason, can we expect this limitation
to be removed in the future?
-- 
			Michael Shannon {ihnp4,hplabs}!oliveb!3comvax!mikes