Re: [Boost-users] [date_time] Stricter stream input validation

From: Johan Nilsson (r.johan.nilsson_at_[hidden])
Date: 2006-09-26 03:15:16

Jeff Garland wrote:
> Johan Nilsson wrote:
>> Hi,
>>
>> is there any way to force ptime stream input fail when the time
>> duration part is not between 00:00:00 and 23:59:59?
>>

[snip]

>
> Since these are treated as a time_duration for i/o there isn't a
> switch in the library to do this.  I think the easiest way to do this
> would be to break down the streaming into it's parts and check in
> your client code.  Here's the sketch if how it can be trivially done:
>
> ptime getTime(istream& is)
> {
>    //assuming formatting is already set...
>    date d;
>    time_duration td;
>    is >> d;
>    is >> td;
>    if (td > hours(24)) {
>      throw ....
>    }
>    return ptime(d, td);
> }

Hmmm, upon closer thought this will also pass for times such as "22:99:00". 
I'd need to check all parts, which feels a bit disturbing.

I realize that a "time_duration" doesn't necessarily correspond to a valid 
time of day. How about implementing something like 
boost::posix_time::time_of_day, which would validate such things on input? 
At least for me it's a bit unintuitive that it's possible to sucessfully 
stream in a ptime when the time part isn't really a valid clock time.

Regards,

Johan