dereferencing null

[Jason House]

On Monday, 5 March 2012 at 04:39:59 UTC, Adam D. Ruppe wrote:

> Huh, I thought there was one in phobos by now.
>
> You could spin your own with something like this:
>
> struct NotNull(T) {
>   T t;
>   alias t this;
>   @disable this();
>   @disable this(typeof(null));
>   this(T value) {
>      assert(value !is null);
>      t = value;
>   }
>
>   @disable typeof(this) opAssign(typeof(null));
>   typeof(this) opAssign(T rhs) {
>       assert(rhs !is null);
>       t = rhs;
>       return this;
>   }
> }
>

The opAssign kills all type safety. I think only NotNull!T should 
be accepted... So "foo = bar" won't compile if bar is nullable. 
To fix, "foo = NotNull(bar)",