pub type Imp = unsafe extern "C" fn();Expand description
A pointer to the start of a method implementation.
The first argument is a pointer to the receiver, the second argument is the selector, and the rest of the arguments follow.
§Safety
This is a “catch all” type; it must be transmuted to the correct type before being called!
Also note that this is non-null! If you require an Imp that can be null,
use Option<Imp>.