Re: [boost] safe integer library -- the scope

Subject: Re: [boost] safe integer library -- the scope
From: Robert Ramey (ramey_at_[hidden])
Date: 2015-12-14 11:39:50

On 12/14/15 5:15 AM, Andrzej Krzemienski wrote:

>>>> Then it can be known at compile time that y can never overflow so no
>>>> runtime checking is required.  Here we've achieved the holy grail:
>>>>
>>>> a) guaranteed correct arithmetic result
>>>> b) no runtime overhead.
>>>> c) no exception code emitted.
>>>> d) no special code - we just write algebraic expressions
>>>>
>>>> This is the true motivation for safe_..._range
>>
>> Why isn't that the behavior of your safe type in the first place?

it is

That is,
>> what benefit does your safe type offer that it shouldn't just be supplanted
>> by the range type?

safe<T> can be used as a drop in replacement for T . safe...range cannot.

>> However, since min() and max() are now constexpr, that all can be
>> collapsed into a single template with three parameterizing types: the
>> underlying type, the minimum, and the maximum:
>>
>> template
>> <
>>     class T
>>   , T Min = std::numeric_limits<T>::min()
>>   , T Max = std::numeric_limits<T>::max()
>>>
>> class safe;

That's exactly what safe<T> is.

> Current implementation has more of these policies (e.g., for how you want
> to report overflow).

Is there a question in there somewhere?