Exercises

The following sections have a few exercises for you.

Exercise 5.1

Extend our current EventStream implementation to include a function called take. It works much like Clojure's core take function for sequences: it will take n items from the underlying event stream, after which, it will stop emitting items.

A sample interaction, which takes the first five items emitted from the original event stream, is shown here:

(def es1 (from-interval 500)) 
(def take-es (take es1 5)) 
 
(subscribe take-es #(prn "Take values: " %)) 
 
;; "Take values: " 0 
;; "Take values: " 1 
;; "Take values: " 2 
;; "Take values: " 3 
;; "Take values: " 4 

Keeping some state might...