def delete(key, options = {})
      return super if options.include?(:raw)
      value, expires = super
      value if !expires || Time.now <= Time.at(expires)
    end
def delete(key, options = {})
      return super if options.include?(:raw)
      value, expires = super
      value if !expires || Time.now <= Time.at(expires)
    end
(see Proxy#delete)