2 problems I can't get my head around

[Manu]

On 28 November 2012 15:07, tn <no at email.com> wrote:

> On Tuesday, 27 November 2012 at 21:16:41 UTC, Walter Bright wrote:
>
>> On 11/27/2012 9:51 PM, Manu wrote:
>>
>>> There's another you missed:
>>> enum X = 10;
>>> I would have imagined this would be semantically identical to E.A/E.B,
>>> but the compiler seemed to view this as distinct in my experiments.
>>>
>>
>> Those are not enums, they are manifest constants. What distinguishes a
>> manifest constant from, say:
>>
>>     const Y = 11;
>>
>> is that no storage is allocated for X, and X's address cannot be taken.
>>
>
> What distinguishes manifest constants from literals? Aren't manifest
> constants just literal aliases? That is, if the following did work
>
> alias Y = 11;
>
> wouldn't that be exactly same as
>
> enum Y = 11;
>
> Perhaps using "alias" instead of "enum" would make the meaning clearer?
>

Interesting concept, but as far as the docs suggest, it's like this:
(In fear of dragging a conversation in a bug report to the NG (probably
more appropriate here)...)

enum E { X = 10 }  // enum definition
enum    { X = 10 }  // anonymous enum
enum      X = 10;   // sugar for anon enums with a single value

This is how it's documented, and it makes perfect sense to me. I like it.
In fact, I found this concept super-endearing when I initially started
using D a lot over C++.
All X's above should be identical (albeit the first has a named scope),
they're all enum values.

E is the type here, it's the only thing that an instance may be created of.
X, equally in all cases, is just a constant value. I'm not sure how the
language syntax distinguishes it from a literal (I'm not sure why it would
have to), but it does seem the compiler distinguishes each of these X's
from each other in some cases.
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