DIPX: Enum Literals / Implicit Selector Expression

[bauss]

On Friday, 3 December 2021 at 04:58:51 UTC, Dave P. wrote:
> On Friday, 3 December 2021 at 04:25:06 UTC, Elronnd wrote:
>> On Friday, 3 December 2021 at 02:38:18 UTC, Dave P. wrote:
>>> Where this really shines are with bit flags.
>>
>> Bitflags are a case where 'with' _does_ work.
>>
>> More generally, I'm sceptical of the feature for the reasons 
>> Dennis and Paul mention; there is clearly some advantage wrt 
>> boilerplate in some cases, but not for bitflags.
>
> Except that `with` introduces a new scope and can’t be used at 
> file scope:
>
> ```d
> enum Flags {
>     FOO = 1,
>     BAR = 2,
>     BAZ = 4,
>     QUX = 8,
> }
>
> void main(){
>     with(Flags){
>         auto flags = FOO | BAR | BAZ | QUX;
>     }
>     // flags does not exist here.
> }
>
> with(Flags){ // Illegal
>     auto f = FOO | BAR;
> }
> ```
>
> With is also very noisy syntactically when all you want is to 
> use enums in a nicer way.

You could do this however:

```d
     Flags flags;
     with(Flags){
         flags = FOO | BAR | BAZ | QUX;
     }
     // flags does exist here now.
```