gistfile1.cl

(defgeneric put-method-for (mode)
  (:method ((mode (eql :replace))) #'kcdbset)
  (:method ((mode (eql :keep))) #'kcdbadd)
  (:method ((mode (eql :concat))) #'kcdbappend))

(defun put (key value &key (mode :replace))
  (funcall (put-method-for mode) key value))  
  
;; definitions of methods for kcdbset, kcdbadd, and kcdbappend define methods
;; that store key/value pairs with different behaviors based on whether
;; that key already exists.  
;; For more info see: http://github.com/isterin/cl-kyoto-cabinet
  
;; Usage...

;; Will store some_val under some_key
(put "some_key" "some_val" :mode :replace)

;; Will not do anything, as it will invoke kcdbadd, which does 
;; nothing if the key exists
(put "some_key" "some_val" :mode :keep)

;; Will add some_val2 to some_key by using kcdbappend
(put "some_key" "some_val2" :mode :concat)