List Functions

We have already introduced the list type. A list storing values of type a has type [a]. Such a list is either empty, [], or consists of an element x followed by a list xs containing the remaining elements, x : xs.

data [] a = [] | a : [a]

I have also used a number of different list functions as examples of recursion and other programming constructs in previous chapters. For reference, we will collect them here in one place.