Hi Alex,
I might have encountered a bug related to (sect) and it's handling of
NIL as element of the first passed list:
: (sect (list NIL) NIL)
-> (NIL) # expected ()
It is not dependent on the second argument being the empty list:
: (sect (list 1 2 NIL 4) (list 2 3 4))
-> (2 NIL 4) # expected (2 4)
A possibly related bug can be found with (diff):
: (diff (list 1 2 NIL 4) NIL)
-> (1 2 4) # expected (1 2 NIL 4)
: (diff (list 1 2 NIL 4) (list 2 3 4))
-> (1) # expected (1 NIL)
I encountered this behavior on version 20.7.4 and am unsure if it
already was fixed in a newer release.
Thanks,
Morris
