[texhax] Misplaced parentheses

[Philip Taylor (Webmaster, Ret'd)]

Donald Arseneau wrote:

> 2) The character d in computer modern math italic has the wrong
> bounding box. This is a typical Knutian ad-hoc-hack so that
> "dx" looks like a differential instead of d times x.  Compare
> $d\vrule = \l\vrule$.

I confess that, when I read this, I was shaken to the core.
I know that one must expect one's idols to have feet of clay,
but to learn that Don had fudged mathit "d" so that differentials
would look better was not something that I had expected.

Worse, I then did my own tests, and compared the following :

	\hbox to 3 em {\hfill $df$}
	\hbox to 3 em {\hfill $lf$}
	\end

and the differences there are nothing short of staggering.

This is, in part, explained by Donald's analysis of the
bounding box, but one also finds in "mathit.mf" :

	ligtable "d": "Y" kern u#, "Z" kern-u#, "j" kern-2u#, "f" kern-3u#, % $d:$

I now feel rather depressed.
** Phil.