Holds if callable
c is designed for chaining. The following must
cmust be declared in a reference type.
- All callables overriding
cmust be designed for chaining.
chas a body, all (and at least one) returned values must be
chas no body (abstract/interface callable or library callable), the return type of
cmust be a subtype of
c’s declaring type, and
cmust be non-static.