Can we make mixin applications first class at the type level?

[Olivier FAURE]

On Thursday, 21 March 2019 at 11:10:27 UTC, sighoya wrote:
> Awesome. Wouldn't it complicate the grammar of D?,e.g.:
>
> int * p; // does it mean declaring an int or calling * : 
> (Type,Type)->(Type,Type)

He could add an additional syntax, eg alias(expr), which would 
box expressions in places where the grammar expect a type. So, 
this would be forbidden:

     type myCustomType(int, string);

     myCustomType(42, "foobar")* myVar;

But this would be allowed:

     type myCustomType(int, string);

     alias(myCustomType(42, "foobar"))* myVar;

(notice the placement of the * in the second version, which is 
outside of the alias expression, because a postfix * isn't valid 
syntax in an expression)

>>For reasoning about code and hygiene, the use site has to 
>>indicate to the programmer that code is being inserted into the 
>>current scope, rather than just calling a function.
>
> Hygiene isn't the problem as mixins are semi hygenic, in case 
> of collision the collided parts get scoped.

Please make multiple posts when answering different people. Some 
people use this forum as a mailing list, and it's generally 
expected that each message answers one specific message.