Question about interface implementation

[ag0aep6g]

On 21.05.23 11:55, Theo wrote:
> class MerchantShip : Ship
> {
>      private int speed = 0; // If only I had 'private(this)' !!
> 
>      // how do I know this method is actually an implementation of an 
> interface method
>      // and not a method specific to this class?
>      // AND ... how come I can change a @safe interface method into a 
> @trusted one?
>      public @trusted void setSpeed(int speed)
>      {
>          int *s = void; // Mmmm.. and my interface all had @safe methods!!
>          this.speed = speed;
>      }
[...]
> }

As far as I understand, a method that has the right signature is always 
an implementation of the interface. There is no way to make a method of 
the same name, with the same parameters, etc. that is "specific to the 
class".

@trusted means that you're allowed to use @system features in the 
implementation while the function must follow the restrictions of @safe 
when called. Since @trusted functions are guaranteed (by the programmer) 
to be safe, they are allowed to overload/implement @safe 
functions/prototypes.

If you create an @trusted function that is not safe to call, that's an 
error on your part.