Re: mm(7) DT string and super/subscripts (was: troff Memorandum Macros documentation derived from the paper "MM - Memorandum Macros")

[Tadziu Hoffmann]

> .ds { \v'-.9m\s'\En[.s]*7u/10u'+.7m'

Wow.  I didn't know that was possible.  You're interrupting the
calculation of the amount of vertical movement to set the point
size, and then use the new value (as ems) in the interrupted
calculation...

But the result is correct, it's equivalent to

  \v'-0.41m'\s'\n[.s]*7/10'

where -0.41 = -0.9 + 0.7*7./10.