Performance optimization for minElement and maxElement

[Nick Treleaven]

On Monday, 12 September 2022 at 14:15:45 UTC, Steven 
Schveighoffer wrote:
> On 9/12/22 7:53 AM, Sergey wrote:
> One thing that is worrisome though, is the fact that `min` and 
> `max` aren't always the minimum and maximum bit patterns 
> available. So short-cutting the search might do something you 
> don't want.

Are they only broken for enum?

> e.g. an enum which defines a bitfield might have values of 1, 
> 2, 4, 8, but instances of the enum might go all the way up to 
> 15 (all bits set). However, the `.max` value would be 8.

Actually dmd allows other operations besides `|` and `&` on enum 
members:

```d
enum E
{
	a,
	b=5,
	c=2
}
pragma(msg, E.max); // E.b

immutable E e = E.b << 1;
pragma(msg, e); // cast(E)10

immutable E f = E.b + E.b + E.b;
pragma(msg, f); // cast(E)15
```

All bits set for E would be 7. I don't know why those operations 
are allowed.