:: [t] -> Int package:rio

length :: Foldable t => t a -> Int
rio RIO.List RIO.Prelude
Returns the size/length of a finite structure as an Int. The default implementation is optimized for structures that are similar to cons-lists, because there is no general way to do better.
genericLength :: Num i => [a] -> i
rio RIO.List
The genericLength function is an overloaded version of length. In particular, instead of returning an Int, it returns any type which is an instance of Num. It is, however, less efficient than length. 
>>> genericLength [1, 2, 3] :: Int
3

>>> genericLength [1, 2, 3] :: Float
3.0
length :: Vector v a => v a -> Int
rio RIO.Vector
O(1) Yield the length of the vector
basicLength :: Vector v a => v a -> Int
rio RIO.Vector.Unsafe
Assumed complexity: O(1) Yield the length of the vector.