infix operator to create a list from head h and a production
function f

This can be used, e.g., as follows:

Ex1: the identity can be used to repeat the same element


will create 1,1,1,1,...

Ex2: To create a list of all integers, use


which will produce 0,1,2,3,4,5,...

Ex3: The call


will produce the powers of two: 1,2,4,8,16,32,...