all_distinct/1

all_distinct(+Vars)

True iff Vars are pairwise distinct. For example, all_distinct/1 can detect that not all variables can assume distinct values given the following domains:

?- maplist(in, Vs,
           [1\/3..4, 1..2\/4, 1..2\/4, 1..3, 1..3, 1..6]),
   all_distinct(Vs).
false.