Optional and orElse: design feedback/critique?

[Alexandru Ermicioi]

On Saturday, 27 July 2019 at 17:59:19 UTC, Johannes Loher wrote:
> Am 27.07.19 um 19:15 schrieb aliak:

>
> ```
> import optional;
>
> auto orElseThrow(alias fun, T)(auto ref Optional!T opt)
> {
>     return opt.orElse!(delegate T() { throw fun(); });
> }
>
> void main()
> {
>     no!int.orElseThrow!(() => new Exception(""));
> }
> ```


Lazy arguments could fit perfectly for orElseThrow statement:

```D
import optional;

auto orElseThrow(T)(auto ref Optional!T opt, lazy Exception 
throwable)
{
     if (opt.empty) {
         throw throwable;
     }

     return opt.front;
}

void main()
{
     no!int.orElseThrow(new Exception("")); // maybe instead of 
no, just optional!int? using just negation is kinda ambiguous.
}
```