vendor/rails/activesupport/lib/active_support/ordered_hash.rb

   1 # OrderedHash is namespaced to prevent conflicts with other implementations
   2 module ActiveSupport
   3   # Hash is ordered in Ruby 1.9!
   4   if RUBY_VERSION >= '1.9'
   5     OrderedHash = ::Hash
   6   else
   7     class OrderedHash < Array #:nodoc:
   8       def []=(key, value)
   9         if pair = assoc(key)
  10           pair.pop
  11           pair << value
  12         else
  13           self << [key, value]
  14         end
  15         value
  16       end
  17
  18       def [](key)
  19         pair = assoc(key)
  20         pair ? pair.last : nil
  21       end
  22
  23       def delete(key)
  24         pair = assoc(key)
  25         pair ? array_index = index(pair) : nil
  26         array_index ? delete_at(array_index).last : nil
  27       end
  28
  29       def keys
  30         collect { |key, value| key }
  31       end
  32
  33       def values
  34         collect { |key, value| value }
  35       end
  36
  37       def to_hash
  38         returning({}) do |hash|
  39           each { |array| hash[array[0]] = array[1] }
  40         end
  41       end
  42
  43       def has_key?(k)
  44         !assoc(k).nil?
  45       end
  46
  47       alias_method :key?, :has_key?
  48       alias_method :include?, :has_key?
  49       alias_method :member?, :has_key?
  50
  51       def has_value?(v)
  52         any? { |key, value| value == v }
  53       end
  54
  55       alias_method :value?, :has_value?
  56     end
  57   end
  58 end