-

private/lru-cache.rkt

@@ -13,6 +13,7 @@
          lru-has?
          lru-add!
          lru-count
+         lru-empty?
          lru->list
          lru-clear
          )
@@ -155,6 +156,10 @@
     )
   )
 
+(define/contract (lru-empty? l)
+  (-> lru*? boolean?)
+  (= (lru-count l) 0))
+
 (define/contract (lru-count lru)
   (-> lru*? larger-equal0?)
   (with-lock lru

scribblings/lru-cache.scrbl

@@ -2,7 +2,7 @@
 @(require scribble/example)
 
 @title{LRU Cache (Least Recently Used) for Racket}
-@author{You}
+@author[@author+email["Hans Dijkema" "hans@dijkewijk.nl"]]
 
 @defmodule[lru-cache]{
 An in-memory LRU cache with optional item expiration. The cache keeps items in
@@ -87,6 +87,10 @@ Clear all items from the cache. Returns @racket[l].
 Return the number of @emph{non-expired} items currently in the cache.
 }
 
+@defproc[(lru-empty? [l lru?]) boolean?]{
+Return @emph{#t} if the number of @emph{non-expired} items currently in the cache equals 0.
+}
+
 @defproc[(lru->list [l lru?] [#:with-expire with-expire? boolean? #f]) list?]{
 Return the cache contents in recency order (most recent first).
 When @racket[with-expire?] is @racket[#f] (default), returns just the list of items.
@@ -120,12 +124,11 @@ a positive integer), otherwise @racket[#f].
 
 @section{Examples}
 
-@examples[
+@#reader scribble/comment-reader 
-  #:eval (make-base-eval)
+[racketblock 
   (require racket/base)
 
-  ;; Assuming your module is "lru.rkt" next to this file:
+  (require lru-cache)
-  (require "../private/lru-cache.rkt")
 
   (define L (make-lru 3))        ;; max 3 items, no expiration
   (lru-add! L 'a)