# File lib/cache_manager.rb, line 92
  def get(key, &block)
    if @cache.key? key
      if ! @expire or @timestamp[key] >= Time.now - @expire
        @timestamp[key] = Time.now
        return @cache[key]
      end
    end
    block ||= @block
    block ? self[key] = block.call(key) : nil
  end