Is a data structure (based in probability) that can be used to do queries about if an item is in a set. If the item is not in the collection you obtain a "100% probability of not in the set", if your item is in the set you obtain instead a "maybe in the collection".<p><pre><code> (ql:quickload "cl-bloom")
(in-package :cl-bloom)
(setf *mydiet* (make-filter :CAPACITY 256 :false-drop-rate *FALSE-DROP-RATE*)
;; default false-drop-rate = 1/1000
;; returns #<BLOOM-FILTER #x000325FC7B028>
(add *mydiet* "hamburguer") ;; add lots of items, returns NIL
(add *mydiet* "salad")
;; ask if an element is yet in the collection
(memberp *mydiet* "hamburguer") ;; T (I can be wrong)
(memberp *mydiet* "orange");; NIL (definitely not)</code></pre>