:: Ord a => [a] -> [a]

The sort function implements a stable sorting algorithm. It is a special case of sortBy, which allows the programmer to supply their own comparison function. Elements are arranged from from lowest to highest, keeping duplicates in the order they appeared in the input.
```>>> sort [1,6,4,3,2,5]
[1,2,3,4,5,6]
```
Extract the elements after the head of a list, which must be non-empty.
Return all the elements of a list except the last one. The list must be non-empty.
reverse xs returns the elements of xs in reverse order. xs must be finite.
cycle ties a finite list into a circular one, or equivalently, the infinite repetition of the original list. It is the identity on infinite lists.
List of elements of a structure, from left to right.
O(n^2). The nub function removes duplicate elements from a list. In particular, it keeps only the first occurrence of each element. (The name nub means `essence'.) It is a special case of nubBy, which allows the programmer to supply their own equality test.
```>>> nub [1,2,3,4,3,2,1,2,4,3,5]
[1,2,3,4,5]
```
forever act repeats the action infinitely.
A flexible variation parameterised in a type constructor