Cast (converting) possibility

[iskandarem]

Think and implement a cast possibility for equatable, so that users could cast castable types.

for example if we have:
class A {}
class B : A {}
Equatable must cast B to A and then check for equality.
Something like:
(A)B

or
double a; -> when they are objects at first
int b;
a is equal to b
like
class X { public object a; }
class Y { public object b; }

The control should be given to the user so they can decide whether to use this during equality checks or not.