More operators inside `is(...)` expressions

[Timon Gehr]

On 24.08.20 13:49, Steven Schveighoffer wrote:
>>
> 
> Yes. If you write !is(T == void), then you are already not checking 
> whether T is defined. This is no different.
> 

So far the pattern is `is(S op T)`. It checks whether S is a valid type 
and then checks `S op T`.

> This literally is just a nicer way to write it, where the operation is 
> closer to the parameters, instead of partly outside the expression.

(I think the implications any of this has for the compiler 
implementation or the user experience has been greatly exaggerated.)