Allow illegal code in enum initialization?

[simendsjo]

On Wednesday, 23 October 2013 at 16:27:47 UTC, Ali Çehreli wrote:
> On 10/23/2013 02:55 AM, simendsjo wrote:
>> Illegal code is accepted in static if, but not in enum 
>> declarations.
>> This leads to having three lines when one is enough. Is this 
>> just an
>> oversight, or by design?
>>
>> template T(alias A) {
>>     enum T = true;
>> }
>>
>> void main() {
>>     struct S { }
>>     static if(__traits(compiles, S.a) && T!(S.a)) // ok
>>         enum e1 = true;
>>     else
>>         enum e1 = false;
>>     enum e2 = __traits(compiles, S.a) && T!(S.a); // No 
>> property S.a
>> }
>
> I don't know whether it is even specified but it feels like a 
> feature to me.
>
> Just like the shortcut behavior of runtime if helps with 
> avoiding illegal memory accesses, this helps with avoiding 
> illegal code altogether:
>
> // null access avoided
> if ((p !is null) && (p.member == 42))
>
> // illegal code avoided
> static if (__traits(compiles, S.a) && (S.a == 42))
>
> Ali

The question is if it would make sense to allow it for enum as 
well as static if. As enum is a compile-time constant I think it 
would be consistent.