heimdallr is a library for Context-Oriented Programming in Clojure.
Simply add this to your leiningen deps: [heimdallr "0.2.0"]
The documentation can be found here: http://eduardoejp.github.com/heimdallr/
(use 'heimdallr)
(def employer {:name "Q-Box Technologies"})
(def person {:name "Eduardo Julián", :employer employer, :address "c/ Manuel Rodriguez Objío, Santo Domingo"})
(deflayer employer-layer)
(deflayer address-layer)
(deflayered to-str [person] (str "Name: " (:name person) "\n"))
(deflayered to-str employer-layer [person] (str (proceed person) "Employer: " (:name (:employer person)) "\n"))
(deflayered to-str address-layer [person] (str (proceed person) "Address: " (:address person) "\n"))
(println (to-str person))
(with-layer address-layer
(with-layer employer-layer
(println (to-str person))))
; The above code is the same as the following.
(with-layer [address-layer employer-layer]
(println (to-str person)))
For more information about Context-Oriented Programming, please visit the following websites: