equivariant functions

[Andrei Alexandrescu]

Robert Fraser wrote:
> Andrei Alexandrescu wrote:
>> Yah, that's where the PassQual template is needed. I'd agree without 
>> joy that, if handling true equivariance is too unwieldy, we can resign 
>> to solving only equivariance in qualifier.
> 
> FWIW, people have done without type eqivariance w/o complaint since 
> static typing was invented. People have been complaining about const 
> equivariance since at least C++ and D makes it worse.

Well Scala, Eiffel and probably other languages have support for at 
least equivariance of the current object. I always forget the name of 
that feature.

Andrei