Martin Schoenert wrote in reply to my query:

Can you give us a concrete example where this does *not* happen.
When I try it, I always get the empty list.

gap> [ [ 1, 2 ], [ 3, 4 ] ] * [];
[ ]
gap> 2 * [];
[ ]

I seem to have made a mistake. It turns out that *both* of my lists were
empty where the problem occurred, so [] * [] returns an error, which I have
no serious objection to.

Sorry for the confusion,

Cheers,
Michael.

---------------------------------/|-|--|-|--|-Michael-Smith------------------
 Michael.Smith@maths.anu.edu.au /-| |\ | |  | Mathematics (CMA)
-------------------------------/--|-|-\|-|_/|-Australian-National-University-

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