Re: [boost] Checked Integral Class

From: Andrey Semashev (andysem_at_[hidden])
Date: 2005-09-15 14:05:39

Dan McLeran wrote:
> I've written a template class to hold a range of valid integral
> values. My intent was to mimic Ada's ability to define a type like
> this:
> type SmallInt is range -10 .. 10;
>
> One can then declare objects of this type and any subsequent
> assignment that violated this range constraint woud throw an
> exception.
> I have built a C++ template class that does the same thing:
>
> template<typename T, T min, T max>
> struct CheckedIntegralValue
>

Just a small proposal. It would be nice if CheckedIntegralValue would chose 
the actual type of value itself. For example, for range -10 .. 10 it would 
use signed char, for -1000 .. 1000 signed int, and for 0 .. 300 unsigned 
int. Of course, its type detecting logic should be overrideable. I think, it 
would look something like:

template< signed long long min, signed long long max, typename T = typename 
auto_detected< min, max >::type, typename BoundingPolicyT = 
throw_on_overflow >
struct CheckedIntegralValue;