Re: [Boost-users] [review][constrained_value] Review of Constrained Value Library begins today

Subject: Re: [Boost-users] [review][constrained_value] Review of Constrained Value Library begins today
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2008-12-03 04:34:50

Jeff Garland wrote:

>       bounded_int<int, 0, 23>::type hour;
>       hour = 20; // OK
>       hour = 26; // exception!
> 
> Behavior in case of assignment of an invalid value can be customized. 

I think this is wrong.
Providing an invalid value should be a non-recoverable programming error.
Non-recoverable means it should abort the program, and programming error 
means it should only be enabled in debug mode.
i.e. an assert is the best choice to assert the preconditions are met.

Apart from that, wouldn't it be more interestin, when multiplying a 
bounded_int<int, 0, 23> by 2, to yield a bounded_int<int, 0, 46> instead 
of attempting to keep the object with the same constraint?
Of course, that only works with bounded_int and not constraints in general.