Why is this not allowed?

[Salih Dincer]

On Monday, 7 October 2024 at 17:20:00 UTC, ryuukk_ wrote:
>
> We went from trying to do that:
>
> ```d
> struct EntityDef
> {
>     struct
>     {
>         int hp;
>     } stats;
> }
> ```
>
>
> to getting suggested to do that instead:
>
> ```d
> struct Foo
> {
>     int bar;
>
>     //struct {/*
>     Baz baz;
>     struct Baz
>     {
>         auto opAssign(int value)
>           => baz = value;//*/
>         int baz;
>     }
> }
>
> void main()
> {
>     Foo foo;
>     foo.bar = 7;
>     foo.baz = 42;
>
>     imported!"std.stdio".writeln(foo); /*
>     with opAssign()      Anonymous
>     Foo(7, Baz(42))  or  Foo(7, 42)    */
> }
> ```

I understand you, but you misunderstood me. You probably brought 
up a problem that can't be solved quickly (or ever). I wanted to 
acknowledge D's praise and bring a different perspective. Would 
this solution work for you?

```d
template Foo() { int hp; }
struct EntityDef
{
   mixin Foo stats;
}

void main()
{
   auto num = EntityDef(41);
   assert(num.stats.hp == 41);

   with(num)
   {
     stats.hp = 42;
     assert(stats.hp == 42);
   }
}
```

SDB at 79