(call-met name receiver ..args)
  name: a sym
  receiver: an obj, a class, or an rdata
  args: zero or more arguments (any type)
  returns any type

Invokes a method.

If the receiver is an object, name must be the qualified or unqualified name of a method, or a field, constant or property which stores a callable value.

If the receiver is a class, name must be the qualified or unqualified name of a toplevel constant which stores a callable value.

If the receiver is an RData, name must be the exact name of one of the methods which was registered using the RClassBuilder.

call-met supports the ? special syntax. When the method name doesn't actually exist, (call-met (? name) rcv ...) will succeed and return #n.

(call-met 'name rcv) is usually abbreviated as (.name rcv).

Similarly, (call-met (? 'name) rcv) is usually abbreviated as ((? .name) rcv).