Added IndifferentAccess as a way to wrap a hash by a symbol-based store that also can be accessed by string keys

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@581 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 38 insertions, 0 deletions

diff --git a/activesupport/lib/core_ext/hash/indifferent_access.rb b/activesupport/lib/core_ext/hash/indifferent_access.rb
new file mode 100644
index 0000000000..3fe0999866
--- /dev/null
+++ b/activesupport/lib/core_ext/hash/indifferent_access.rb
@@ -0,0 +1,38 @@
+class HashWithIndifferentAccess < Hash
+  def initialize(constructor)
+    if constructor.is_a?(Hash)
+      super()
+      update(constructor.symbolize_keys)
+    else
+      super(constructor)
+    end
+  end
+  
+  alias_method :regular_read, :[]
+  
+  def [](key)
+    case key
+      when Symbol: regular_read(key) || regular_read(key.to_s)
+      when String: regular_read(key) || regular_read(key.to_sym)
+      else regular_read(key)
+    end
+  end
+
+  alias_method :regular_writer, :[]=
+  
+  def []=(key, value)
+    regular_writer(key.is_a?(String) ? key.to_sym : key, value)
+  end
+end
+
+module ActiveSupport #:nodoc:
+  module CoreExtensions #:nodoc:
+    module Hash #:nodoc:
+      module IndifferentAccess
+        def with_indifferent_access
+          HashWithIndifferentAccess.new(self)
+        end
+      end
+    end
+  end
+end