# File activesupport/lib/active_support/cache.rb, line 20
20:     def self.expand_cache_key(key, namespace = nil)
21:       expanded_cache_key = namespace ? "#{namespace}/" : ""
22: 
23:       if ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"]
24:         expanded_cache_key << "#{ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"]}/" 
25:       end
26: 
27:       expanded_cache_key << case
28:       when key.respond_to?(:cache_key)
29:         key.cache_key
30:       when key.is_a?(Array)
31:         key.collect { |element| expand_cache_key(element) }.to_param
32:       when key.respond_to?(:to_param)
33:         key.to_param
34:       else
35:         key.to_s
36:       end
37: 
38:       expanded_cache_key
39:     end

    # File activesupport/lib/active_support/cache.rb, line 5
 5:     def self.lookup_store(*store_option)
 6:       store, *parameters = *([ store_option ].flatten)
 7: 
 8:       case store
 9:       when Symbol
10:         store_class_name = (store == :drb_store ? "DRbStore" : store.to_s.camelize)
11:         store_class = ActiveSupport::Cache.const_get(store_class_name)
12:         store_class.new(*parameters)
13:       when nil
14:         ActiveSupport::Cache::MemoryStore.new
15:       else
16:         store
17:       end
18:     end