Use Hash for Memoizable::Memory instead of ThreadSafe::Cache

lib/memoizable.rb

@@ -1,8 +1,5 @@
 # encoding: utf-8
 
-require 'monitor'
-require 'thread_safe'
-
 require 'memoizable/instance_methods'
 require 'memoizable/method_builder'
 require 'memoizable/module_methods'

lib/memoizable/memory.rb

@@ -11,8 +11,7 @@ class Memory
     #
     # @api private
     def initialize
-      @memory  = ThreadSafe::Cache.new
-      @monitor = Monitor.new
+      @memory  = Hash.new
       freeze
     end
 
@@ -39,9 +38,9 @@ def [](name)
     # @api public
     def []=(name, value)
       memoized = true
-      @memory.compute_if_absent(name) do
+      @memory.fetch(name) do
         memoized = false
-        value
+        @memory[name] = value
       end
       fail ArgumentError, "The method #{name} is already memoized" if memoized
     end
@@ -55,12 +54,8 @@ def []=(name, value)
     #
     # @api public
     def fetch(name)
-      @memory.fetch(name) do       # check for the key
-        @monitor.synchronize do    # acquire a lock if the key is not found
-          @memory.fetch(name) do   # recheck under lock
-            self[name] = yield     # set the value
-          end
-        end
+      @memory.fetch(name) do
+        self[name] = yield
       end
     end
 

memoizable.gemspec

@@ -18,7 +18,5 @@ Gem::Specification.new do |gem|
   gem.test_files       = Dir.glob('spec/{unit,integration}/**/*.rb')
   gem.extra_rdoc_files = Dir.glob('**/*.md')
 
-  gem.add_runtime_dependency('thread_safe', '~> 0.1.3')
-
   gem.add_development_dependency('bundler', '~> 1.3', '>= 1.3.5')
 end