is(x = module) vs. __traits(isModule, x)

[Meta]

On Wednesday, 7 October 2020 at 20:41:19 UTC, Stefan Koch wrote:
> On Wednesday, 7 October 2020 at 20:37:47 UTC, Meta wrote:
>> On Wednesday, 7 October 2020 at 20:19:57 UTC, Paul Backus 
>> wrote:
>>> Couldn't you unconditionally lower <Node>.__isModule to 
>>> __traits(isModule, <Node>) regardless of what type of node it 
>>> is, and rely on the existing error messages for incorrect 
>>> trait arguments? You don't have to worry about shadowing 
>>> "real" properties, because anything that starts with "__" is 
>>> a reserved identifier.
>
>>     if (__traits(compiles, mixin(`__traits(%s, sym, 
>> Args)`.format(name))))
>>     {
>>         enum opDispatch = mixin(`__traits(%s, sym, 
>> Args)`.format(name));
>>     }
>> }
>
>
> As a little side notion.
> Avoid the use of std.format.format at CTFE.
> It's very expensive.
> And please cache the string :)

I'm hoping and praying for a string interpolation dip that gets 
accepted.