module I18n::Backend::Memoize

def available_locales
  @memoized_locales ||= super
end

def lookup(locale, key, scope = nil, options = {})
  flat_key  = I18n::Backend::Flatten.normalize_flat_keys(locale,
    key, scope, options[:separator]).to_sym
  flat_hash = memoized_lookup[locale.to_sym]
  flat_hash.key?(flat_key) ? flat_hash[flat_key] : (flat_hash[flat_key] = super)
end

def memoized_lookup
  @memoized_lookup ||= Hash.new { |h, k| h[k] = {} }
end

def reload!
  reset_memoizations!
  super
end

def reset_memoizations!(locale=nil)
  @memoized_locales = nil
  (locale ? memoized_lookup[locale.to_sym] : memoized_lookup).clear
end

def store_translations(locale, data, options = {})
  reset_memoizations!(locale)
  super
end