Choice returns a random element from the given slice.

Integer returns an integer in [mn..mx].

Selection returns a slice of 'n' random entries from the given slice.

WeightedChoice returns an element from the given slice of options where elements with a higher weight are more likely to be selected.

ErrChoiceIsEmpty is returned if the user attempts to choose from an empty slice.

WeightedChoiceOption pairs a type with a weight.