On 2011-06-27 03:30:09 -0400, Nub Public <nubpub...@gmail.com> said:
class B
{
void fun() { writeln("B"); }
}
class D : B
{
override void fun() { writeln("D"); }
}
void delegate() dg = &b.fun;
dg.ptr = cast(void*)d;
dg();
Compiler: DMD 2.053
It prints "B" instead of "D".
The equivalent code in C++ prints "D" nicely.
C++ doesn't have delegates, and D doesn't have member function
pointers. Resolving virtual functions is done while you take its
address in D, while in C++ the member function pointer type contains
holds the vtable offset (or several in the case of multiple
inheritance) which gets resolved only when you call the function.
If you want the C++ behaviour, try using a delegate literal as a
trampoline that gets the object as a parameter to then call your
function:
void delegate(B b) dg = (B b) { b.fun(); };
dg(d);
--
Michel Fortin
michel.for...@michelf.com
http://michelf.com/
