class Jbuilder::KeyFormatter

def format(key)
  @cache[key] ||= @format.inject(key.to_s) do |result, args|
    func, args = args
    if ::Proc === func
      func.call result, *args
    else
      result.send func, *args
    end
  end
end

def initialize(*args)
  @format = {}
  @cache = {}
  options = args.extract_options!
  args.each do |name|
    @format[name] = []
  end
  options.each do |name, parameters|
    @format[name] = parameters
  end
end

def initialize_copy(original)
  @cache = {}
end