Re: [boost] asio review

From: Sebastian Redl (sebastian.redl_at_[hidden])
Date: 2005-12-21 08:54:42

Christopher Kohlhoff wrote:

>>I think the following code-snippet in the tutorial could be
>>written more elegantly, through an interface change of the
>>deadline_timer:
>>
>>{ boost::asio::deadline_timer t; ...
>>t.expires_at(t.expires_at() + boost::posix_time::seconds(1));
>>}
>>
>>by giving direct access to the time member.
>>
>>t.expiry_date()+=boost::posix_time::seconds(1); For more
>>complex cases or error-checking, some proxy classes could be
>>used.
>>    
>>
>
>Doesn't such an approach force a particular internal
>implementation on the timer?
>  
>
Actually, no. It's pretty easy to write a proxy object to do this stuff. 
A minimal object, just for the above example:

class expiry_date_proxy
{
  deadline_timer &timer;

public:
  expiry_date_proxy(deadline_timer &t) : timer(t) {}

  expiry_date_proxy & operator +=(timespan ts) {
    timer.expires_at(timer.expires_at() + ts);
  }
};

class deadline_timer
{
 ...
  expiry_date_proxy expiry_date() { return expiry_date_proxy(*this); }
};

I'm not saying that this necessarily should be done (in particular, 
where do you stop making properties?), but it's possible.

Sebastian Redl