On Friday, 24 October 2014 at 00:21:52 UTC, Etienne Cimon wrote:
On 2014-10-23 20:12, bearophile wrote:
In D all class instances contain a pointer to the class and a
monitor
pointer. The table is used for run-time reflection, and for
standard
virtual methods like toString, etc.
Bye,
bearophile
So what's the point of making a class or methods final? Does it
only free some space and allow inline to take place?
Like bearophile said the vtable is required for virtual methods.
Consider this code:
import std.stdio : writeln;
class A { void foo() {writeln("A");} }
final class B : A { override void foo() {writeln("B");} }
void main() {
A a = new B();
a.foo();
}
In order for the call to foo to run the correct version of foo, B
needs to have a vtable. Since all classes in D implicitly inherit
from Object, which has some virtual methods, all classes need to
have a vtable.
--
Simen
