Data.Sequence 'index' documentation may be incorrect.

In the documentation for Data.Sequence.index: index :: Seq a -> Int -> a O(log(min(i,n-i))). The element at the specified position, which should be a positive integer less than the size of the sequence. If the position is out of range, index fails with an error. == 'a positive integer' refers to an number in the set of {1, 2, 3, …} but through some code discovered that what it really means is a non- negative integer, {0, 1, 2, …} Although it would be more immediately known if it just said it was a 0 based index. - iæfai