From: Robert Klemme <bob.news@...>
Date: 2004-09-28T21:34:20+09:00
Subject: Re: [ANN] ncache 0.9


"George Moschovitis" <george.moschovitis@gmail.com> schrieb im Newsbeitrag
news:1096373667.801902.153440@h37g2000oda.googlegroups.com...
> > What do you mean by complexity?  Storing a single linked list element
> is
> > not really something I'd call "complex".
>
> Hmm, I probably didnt understand your suggestion correctly, can you
> elaborate please? I am very intereseted in your idea.

class LruCache
  ListItem = Struct.new(:obj,:prev,:next)

private
  def create_list_item
    begin
      return @spare || ListItem.new
    ensure
      @spare = nil
    end
  end

  def return_list_item(li)
    @spare ||= li
  end
end

Then use #create_list_item and #return_list_item wherever you create or
release ListItems.

> > *I* would not find this natural.  If I were using a LRU cache I'd
> only
> > expect to have to provide keys that satisfy the same conditions as
> Hash
>
> Well I find natural that a Cache only accepts Cacheable objects (ie
> objects that extend the LRUCache::Item). Like a render that accepts
> renderable objects. As you say we are free to dissagree :-)
> best regards,

Although there is some truth in this, a LRUCache is something more general
than a renderer - in fact it comes close to Hash IMHO.  So there should be
less requirements on container instances than for a renderer.

Regards

    robert