Zwei bug

[MOON5 at MIT-AI (David A. Moon)]

In the 183rd line of the function NZWEI:REDISPLAY, where it's deciding whether
to do an erase-to-eof, appears the test
			       (> (PLINE-TICK WINDOW PLINE) 0)
If the very first display ever done doesn't fill the screen (e.g. start
a fresh world and do (ed 'foo) where foo is a function defined at the end
of a file) this line gets an error because PLINE-TICK is NIL.  But why
this magic zero??  In fact I don't see what this line accomplishes at all
in its containing AND.

Another random bug, while I'm at it.  In Mail mode, c-; inserts a ;-comment
but c-m-; is a no-op.  I think this bug was inherited from Emacs and has to
do with the difference between comment begin and comment start.