On 2011-06-27 07:49:19 -0400, Nub Public <nubpub...@gmail.com> said:
What's the rational for this behavior though? Resolving the address of
a virtual function at compile time seems a little counter-intuitive to
me.
The address for a virtual function isn't necessarily resolved at
compile time. It is resolved at the point where you use the address-of
operator, and that'll check the vtable at runtime if necessary.
In D:
B b = new D;
auto dg = &b.foo; // address is resolved at runtime by looking at the
vtable
dg(); // calls D.foo
In C++:
void (B::*fptr)() = &B::foo;
B b = new D;
b.*fptr(); // vtable lookup here, calls D.foo
I guess this way is slightly more efficient.
It certainly is if you call the delegate more often than you create one.
--
Michel Fortin
michel.for...@michelf.com
http://michelf.com/
