The “minus” as in A-B is only good for a pair, it doesn’t extend to A-B-C. That suffers the exact same problem as “comma lists”, BTW, just swapped:
?- A-B = A-B-C.
A = A-C,
B = C.
The “clean” way to extend - from a pair to a triple, quadriple etc would be to do the exact same thing you’d do with the comma:
','(a, b), ','(a, b, c), ','(a, b, c, d)
-(a, b), -(a, b, c), -(a, b, c, d)
what I now learned and find curious is that others also use v(a, b, ...) for this.