__traits(compiles , mixin ... )

[SrMordred]

On Wednesday, 25 October 2017 at 20:04:47 UTC, Adam D. Ruppe 
wrote:
> On Wednesday, 25 October 2017 at 19:50:31 UTC, SrMordred wrote:
>> so why this line resolves to false?
>
> Because it is illegal to put a statement or declaration inside 
> __traits(compiles). sorry, I should have said that before... 
> even though the mixin can be legal in another context, it won't 
> be in the __traits context due to this:
>
> https://dlang.org/spec/traits.html#compiles
>
> "Returns a bool true if all of the arguments compile (are 
> semantically correct). The arguments can be symbols, types, or 
> expressions that are syntactically correct. The arguments 
> cannot be statements or declarations. "
>
>
> When there's a closing ;, it is a mixin statement.
>
>> void F(){}
>> pragma(msg, __traits( compiles, mixin("F();") ) );//false

Oh, now thats explains. I thought that a "mixin statement" was 
equal to the argument type that it compiles to. Thanks!