For arrays, an array containing all elements present in a and not in b is returne. The order of the remaining values from a will be kept.

For lists, the same operation is done as for arrays, except order is of course not considered.

5-10

returns -5

10-2.0

returns 8.0

({1,2})-({2})

returns ({1})

([1:2,2:1])-([1:0])

returns ([2:1])