====
>>> main.whiley
property unique_elements<T>(T[] items, int end) -> (bool r):
    // All items upto end are unique
    return end >= 0 && end <= |items| &&
           all { i in 0..end, j in (i+1)..end | items[i] != items[j] }

public export method test():
   assert unique_elements([0,0],0)
   assert unique_elements([0,0],1)
   assert unique_elements([0,0],2)
---
E705 main.whiley 9,10:33
E722 main.whiley 9,10:33
=====
>>> main.whiley 7:10
   assert unique_elements([0,1,0],0)
   assert unique_elements([0,1,0],1)
   assert unique_elements([0,1,0],2)
   assert unique_elements([0,1,0],3)
---
E705 main.whiley 10,10:35
E722 main.whiley 10,10:35
=====
>>> main.whiley 7:11
   assert unique_elements([0],0)
   assert unique_elements([0],1)
   //
   assert unique_elements([0,1],0)
   assert unique_elements([0,1],1)
   assert unique_elements([0,1],2)
   //
   assert unique_elements([0,1,2],0)
   assert unique_elements([0,1,2],1)
   assert unique_elements([0,1,2],2)
   assert unique_elements([0,1,2],3)
   //
   assert unique_elements([1,0,2],0)
   assert unique_elements([1,0,2],1)
   assert unique_elements([1,0,2],2)
   assert unique_elements([1,0,2],3)
   //
   assert unique_elements([0,2,1],0)
   assert unique_elements([0,2,1],1)
   assert unique_elements([0,2,1],2)
   assert unique_elements([0,2,1],3)
   
   assert unique_elements([2,1,0],0)
   assert unique_elements([2,1,0],1)
   assert unique_elements([2,1,0],2)
   assert unique_elements([2,1,0],3)
---