Recent minibuffer commands

[Barry Margolin <Margolin at MIT-Multics>]

In ZWEI in Release 4.0, System 222.186, Zmail 74.43,
Experimental Macsyma 6.15, site configuration 12, on Zarniwoop:

Could the code that saves minibuffer commands so that they can be
re-executed with C-X Altmode filter out duplicates, at least duplicates
that immediately follow one another.  If I do Meta-X A, then do Meta-X B
a whole bunch of times in a row, it would be convenient if I could
re-execute the A using C-X Altmode, rather than being given a whole
bunch of choices of B.