From: Daniel Schierbeck <daniel.schierbeck@...>
Date: 2006-05-13T02:15:44+09:00
Subject: [Facets] Cached proc?

I haven't been able to find a cached proc class in the Facets list, so I 
whipped up one on my own. Pretty basic, but it's nice to have a facet 
for it :)

   class CachedProc
     def initialize(&block)
       @proc = block
       @cache = Hash.new{|cache, args| cache[args] = @proc.call(*args) }
     end

     def call(*args)
       @cache[args]
     end

     alias_method :[], :call

     def method_missing(name, *args, &block)
       @proc.send(name, *args, &block)
     end
   end

   def cached_proc(&block)

   p = cached_proc{|x, y| puts '*'; x * y }
   p.call(2, 3)  => 6
                 -> *
   p.call(2, 3)  => 6


Cheers,
Daniel