code: public BooleanExpression in(T... right) {
          if (right.length == 1) {
              return eq(right[0]);
          } else {
              return Expressions.booleanOperation(Ops.IN, mixin, ConstantImpl.create(ImmutableList.copyOf(right)));
          }
      }
docs: Create a {@code this in right} expression
  
  @param right rhs of the comparison
  @return this in right