Kata

Implement the function unique_in_order which takes as argument a sequence and returns a list of items without any elements with the same value next to each other and preserving the original order of elements.

For example:

uniqueInOrder("AAAABBBCCDAABBB") == {'A', 'B', 'C', 'D', 'A', 'B'}
uniqueInOrder("ABBCcAD")         == {'A', 'B', 'C', 'c', 'A', 'D'}
uniqueInOrder([1,2,2,3,3])       == {1,2,3}

uniqueInOrder('AAAABBBCCDAABBB') == ['A', 'B', 'C', 'D', 'A', 'B']
uniqueInOrder('ABBCcAD')         == ['A', 'B', 'C', 'c', 'A', 'D']
uniqueInOrder([1,2,2,3,3])       == [1,2,3]

uniqueInOrder('AAAABBBCCDAABBB') == ['A', 'B', 'C', 'D', 'A', 'B']
uniqueInOrder('ABBCcAD')         == ['A', 'B', 'C', 'c', 'A', 'D']
uniqueInOrder([1,2,2,3,3])       == [1,2,3]

unique_in_order('AAAABBBCCDAABBB') == ['A', 'B', 'C', 'D', 'A', 'B']
unique_in_order('ABBCcAD')         == ['A', 'B', 'C', 'c', 'A', 'D']
unique_in_order([1, 2, 2, 3, 3])   == [1, 2, 3]
unique_in_order((1, 2, 2, 3, 3))   == [1, 2, 3]

unique_in_order('AAAABBBCCDAABBB') == ['A', 'B', 'C', 'D', 'A', 'B']
unique_in_order('ABBCcAD')         == ['A', 'B', 'C', 'c', 'A', 'D']
unique_in_order([1,2,2,3,3])       == [1,2,3]

uniqueInOrder "AAAABBBCCDAABBB" == "ABCDAB"
uniqueInOrder "ABBCcAD"         == "ABCcAD"
uniqueInOrder [1,2,2,3,3]       == [1,2,3]

unique_in_order("AAAABBBCCDAABBB") == ['A', 'B', 'C', 'D', 'A', 'B']
unique_in_order("ABBCcAD")         == ['A', 'B', 'C', 'c', 'A', 'D']
unique_in_order([1,2,2,3,3])       == [1,2,3]

uniqueInOrder("AAAABBBCCDAABBB")   == List('A', 'B', 'C', 'D', 'A', 'B')
uniqueInOrder("ABBCcAD")           == List('A', 'B', 'C', 'c', 'A', 'D')
uniqueInOrder(List(1, 2, 2, 3, 3)) == List(1, 2, 3)