On Wed, 12 Mar 2014 09:34:32 -0400, Steve Teale
<steve.te...@britseyeview.com> wrote:
On Wednesday, 12 March 2014 at 13:12:20 UTC, Steven Schveighoffer wrote:
On Wed, 12 Mar 2014 09:05:05 -0400, Steve Teale
<steve.te...@britseyeview.com> wrote:
How is the compiler to build it's one copy of bad? Should x be typed as
A or B? Or something not even seen in this module that could derive
from I?
-Steve
Let's take bad() away, and instead:
class A : I
{
A myType() { return cast(A)null;}
final void foo();
}
class B : I
{
B myType() {return cast(B) null;}
final void bar();
}
void main()
{
I[] arr = [new A, new B];
foreach(i; arr) { (cast(typeof(i.myType()) i).foo() }
}
myType() is a virtual function, so calling it through the interface type
should get the correct version right?, and then the cast should cause a
call to A or B.
The type cannot be determined at runtime, it's a static language.
foreach(i; arr) { typeof(i.myType()) x = cast(i.myType()) i; x.foo();}
What is typeof(x)? It needs to be decided at compile time.
-Steve
