Function Z3_mk_distinct 

pub unsafe extern "C" fn Z3_mk_distinct(
    c: Z3_context,
    num_args: c_uint,
    args: *const Z3_ast,
) -> Option<Z3_ast>

Create an AST node representing distinct(args[0], ..., args[num_args-1]).

The distinct construct is used for declaring the arguments pairwise distinct. That is, Forall 0 <= i < j < num_args. not args[i] = args[j].

All arguments must have the same sort.

NOTE: The number of arguments of a distinct construct must be greater than one.