On 2010-09-07 17:29, Don wrote:
Jacob Carlborg wrote:
I'm reading http://www.digitalmars.com/d/2.0/declaration.html#Typeof
where it says:
"typeof(this) will generate the type of what this would be in a
non-static member function, even if not in a member function. "
From that I got the impression that the code below would print the
same result, but it doesn't. It prints:
main.Bar
main.Foo
instead of:
main.Foo
main.Foo
Is this a bug or have I misunderstood the docs?
typeof(this) gives the *compile-time* type of this. Inside Bar, it has
to return 'Bar'.
typeid(this) gives the *runtime* type of this. So it can work that it's
Bar is actually a Foo.
I know that typeof(this) is a compile time expression but in this case I
think the compiler has all the necessary information at compile time.
Note that I'm not calling "method" on a base class reference, I'm
calling it on the static type "Foo". In this case I think typeof(this)
would resolve to the type of the receiver, i.e. the type of"foo".
module main;
import std.stdio;
class Bar
{
void method ()
{
writeln(typeid(typeof(this)));
writeln(typeid(this));
}
}
class Foo : Bar {}
void main ()
{
auto foo = new Foo;
foo.method;
}
--
/Jacob Carlborg
