- slset= LIST_1 LIST_2 ...procedure
Returns true iff every LIST_i is set-equal to LIST_i+1.
"Set-equal" simply means that LIST_i is a subset of LIST_i+1, and LIST_i+1 is a subset of LIST_i.
(slset= '(b e a) '(a e b) '(e e b a)) => #t (slset= '(b e a) '(a e b x) '(e e b a)) => #f (slset=) => #t ; Trivial cases (slset= '(a)) => #t