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From: Joe Gottman on 19 Jun 2008 07:08
Since by definition integral_constant::value must always be a
compile-time constant, it should be constexpr so that the compiler knows
this fact.

Proposed Resolution:
In 20.4.3 replace
static const T value = v;
with
static constexpr T value = v;




Joe Gottman

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From: Triple-DES on 20 Jun 2008 04:23
On 20 Jun, 00:08, Joe Gottman <jgott...(a)carolina.rr.com> wrote:
> Since by definition integral_constant::value must always be a
> compile-time constant, it should be constexpr so that the compiler knows
> this fact.
>
> Proposed Resolution:
> In 20.4.3 replace
> static const T value = v;
> with
> static constexpr T value = v;
>

First of all I don't think you can submit a DR to a draft. Second, I
don't think your proposed change is correct, since value can appear
wherever an integral constant-expression is required. Consider the
following examples:

// typical integral_constant implementation (value definition snipped)
template <class T, T v>
struct integral_constant
{
static const T value = v;
typedef T value_type;
typedef integral_constant<T,v> type;
};

// integral constant required here:
char test[integral_constant<int, 42>::value];
// here too:
integral_constant<int,
integral_constant<int,42>::value> c;

DP


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