How do formally you call the 'in' operator?

[Ellery Newcomer]

On 09/24/2011 01:18 PM, Andrej Mitrovic wrote:
> Information about overloading opIn and opIn_r is missing from the
> docs, so I'm writing that section. But I don't know what is the formal
> name of this operator so I can put it in the title. Maybe I should
> just name the title "Overloading the In Operator"?

I think opIn and friend have been deprecated, and the in vogue thing to
use now is opBinaryRight