December 19
How to manualy declare constructor for struct Ptr which work like Ptr.create?

struct Ptr{
    int* ptr;

    static Ptr create(scope return int* ptr)@safe{
        Ptr x;
        x.ptr = ptr;
        return x;
    }

    /++ This doesn't work:
    this(scope return int* ptr)scope @safe{
        this.ptr = ptr;
    }
    +/
}

void main()@safe{
    int i;
    auto x = Ptr(&i);
    auto y = Ptr.create(&i);
}
December 19
On 12/19/17 8:22 AM, vit wrote:
> struct Ptr{
>      int* ptr;
> 
>      static Ptr create(scope return int* ptr)@safe{
>          Ptr x;
>          x.ptr = ptr;
>          return x;
>      }
> 
>      /++ This doesn't work:
>      this(scope return int* ptr)scope @safe{
>          this.ptr = ptr;
>      }
>      +/
> }
> 
> void main()@safe{
>      int i;
>      auto x = Ptr(&i);
>      auto y = Ptr.create(&i);
> }

I think this is a limitation of dip1000 that was not foreseen. I think when you mark the parameter `return`, `this` isn't actually considered a return value, is it? So it doesn't link the lifetime of ptr to the lifetime of this, which it should.

Please file an enhancement request, this should be allowed.

-Steve