Reduce an Array in a direction.

Array.fromList [ "l", "i", "v", "e" ]
    |> Array.fold FirstToLast (++) ""
--> "live"


Array.fromList [ "l", "i", "v", "e" ]
    |> Array.fold LastToFirst (++) ""
--> "evil"

A certain number of elements from one side.

Array.fromList [ 1, 2, 3, 4, 5, 6 ]
    |> Array.take 4 FirstToLast
    |> Array.take 2 LastToFirst
--> Array.fromList [ 3, 4 ]


Array.fromList [ 1, 2, 3 ]
    |> Array.take 100 FirstToLast
--> Array.fromList [ 1, 2, 3 ]


Array.fromList [ 1, 2, 3 ]
    |> Array.take -100 FirstToLast
--> Array.empty

After a certain number of elements from one side.

Array.fromList [ 1, 2, 3, 4, 5, 6 ]
    |> Array.drop 2 LastToFirst
--> Array.fromList [ 1, 2, 3, 4 ]


Array.fromList [ 1, 2, 3 ]
    |> Array.drop 100 FirstToLast
--> Array.empty


Array.fromList [ 1, 2, 3 ]
    |> Array.drop -100 FirstToLast
--> Array.fromList [ 1, 2, 3 ]

Split the Array into equal-sized chunks. The elements left over on one side are in less.

Array.fromList [ 1, 2, 3, 4, 5, 6, 7 ]
    |> Array.group 3 FirstToLast
--> { groups =
-->     [ [ 1, 2, 3 ], [ 4, 5, 6 ] ]
-->         |> List.map Array.fromList
-->         |> Array.fromList
--> , less = Array.fromList [ 7 ]
--> }


Array.fromList [ 1, 2, 3, 4, 5, 6, 7 ]
    |> Array.group 3 LastToFirst
--> { less = Array.fromList [ 1 ]
--> , groups =
-->     [ [ 2, 3, 4 ], [ 5, 6, 7 ] ]
-->         |> List.map Array.fromList
-->         |> Array.fromList
--> }

Just the element at an index in a direction.

Array.fromList [ "lose", "win", "lose" ]
    |> Array.at 0 LastToFirst
--> Just "lose"


Array.fromList [ 1, 2, 3 ]
    |> Array.at 0 FirstToLast
--> Just "lose"

Nothing, if the index is out of range.

Array.fromList [ 1, 2, 3 ]
    |> Array.at -1
--> Nothing

Set the element at an index in a direction.

Array.fromList [ "I", "am", "ok" ]
    |> Array.replaceAt 2 FirstToLast "confusion"
--> Array.fromList [ "I", "am", "confusion" ]


Array.fromList [ "I", "am", "ok" ]
    |> Array.replaceAt 1 LastToFirst "feel"
--> Array.fromList [ "I", "feel", "ok" ]

If the index is out of range, the array is unaltered.

Array.fromList [ "I", "am", "ok" ]
    |> Array.replaceAt -1 FirstToLast "is"
--> Array.fromList [ "I", "am", "ok" ]

Kick an element out of an Array at a given index in a direction.

Array.fromList [ 'a', 'a', 'b' ]
    |> Array.removeAt 1 FirstToLast
--> Array.fromList [ 'a', 'b', 'c', 'd' ]
Array.fromList [ 'a', 'b', 'c', 'd' ]
    |> Array.removeAt 0 LastToFirst
--> Array.fromList [ 'a', 'b', 'c' ]

If the index is out of bounds, the Array is unaltered.

Array.fromList [ 'a', 'a', 'b' ]
    |> Array.removeAt -1 FirstToLast
--> Array.fromList [ 'a', 'a', 'b' ]

Put an element in an Array at a given index in a direction.

Array.fromList [ 'a', 'c', 'd' ]
    |> Array.insertAt 1 FirstToLast 'b'
--> Array.fromList [ 'a', 'b', 'c', 'd' ]
Array.fromList [ 'a', 'c', 'd' ]
    |> Array.insertAt 2 LastToFirst 'b'
--> Array.fromList [ 'a', 'b', 'c', 'd' ]

If the index is out of bounds, nothing gets inserted.

Array.fromList [ 'a', 'c', 'd' ]
    |> Array.insertAt -1 'b'
--> Array.fromList [ 'a', 'c', 'd' ]
Array.fromList [ 'a', 'c', 'd' ]
    |> Array.insertAt 10 'b'
--> Array.fromList [ 'a', 'c', 'd' ]