[no subject]

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

I started fixing this, but got too deep in lossage, so I'll mail it in instead.
If you tab off the end of the line in Mail mode, it gets an error with a
negative argument to make-array.  The bugs are as follows:

com-tab-to-tab-stop calls sheet-compute-motion instead of sheet-string-length,
thus when it wraps around in the tab-stop buffer it gets a small X-coordinate
which is not where it really wants to tab to.

indent-to given a bp to the end of a line with a lot of tabs in it and
a small place to indent to, instead of deciding it can't indent to there
tries to "grow" the line to a negative length.

com-tab-to-tab-stop doesn't try to do anything reasonable when the
length of the tab stop buffer is exceeded.  Emacs somehow manages to
keep putting in tabs in this case with the default tab stop buffer; I
don't know what it tries to do in general.