Thread overview
Re: Templates everywhere
Mar 15, 2010
Eldar Insafutdinov
Mar 15, 2010
Walter Bright
Mar 15, 2010
Eldar Insafutdinov
March 15, 2010
Walter Bright Wrote:

> Max Samukha wrote:
> > Here is a non-template implementation that should fix the problems (it is a template but only formally):
> 
> Thanks, I've incorporated it.

Thanks for that, but what about the other issues, why does this function have to be a template? Why does calling __dtor doesn't call base class destructors(as it is done in C++)?
March 15, 2010
Eldar Insafutdinov wrote:
> Walter Bright Wrote:
> 
>> Max Samukha wrote:
>>> Here is a non-template implementation that should fix the problems (it is
>>> a template but only formally):
>> Thanks, I've incorporated it.
> 
> Thanks for that, but what about the other issues, why does this function have
> to be a template?

So it works with other types, though that isn't implemented.


> Why does calling __dtor doesn't call base class destructors(as it is done in C++)?

Doing it that way is non-trivial, and I was in a hurry to get the system working. Class destructors are rarely used in D, so doing it the simple way is not a performance issue.

Destructors for structs, however, are done the more complicated (and more performant) way because they need to be more efficient.

March 15, 2010
Walter Bright Wrote:

> Eldar Insafutdinov wrote:
> > Walter Bright Wrote:
> > 
> >> Max Samukha wrote:
> >>> Here is a non-template implementation that should fix the problems (it is a template but only formally):
> >> Thanks, I've incorporated it.
> > 
> > Thanks for that, but what about the other issues, why does this function have to be a template?
> 
> So it works with other types, though that isn't implemented.


This code:
-------

void clear(Dummy = void)(Object obj)
{
    pragma(msg, "template instance: Object clear");
}

void clear(T)(ref T obj) if (!is(T == class))
{
    pragma(msg, "template instance: " ~ T.stringof ~ " clear");
}

class Boo {}
class Foo {}
struct Bar {}
struct Baz {}

void main()
{
    auto boo = new Boo;
    auto foo = new Foo;
    Bar bar;
    Baz baz;
    clear(boo);
    clear(foo);

    clear(bar);
    clear(baz);
}

-------
outputs during compilation:

template instance: Object clear
template instance: Bar clear
template instance: Baz clear

Isn't that what you need?

> 
> > Why does calling __dtor doesn't call base class destructors(as it is done in C++)?
> 
> Doing it that way is non-trivial, and I was in a hurry to get the system working. Class destructors are rarely used in D, so doing it the simple way is not a performance issue.
> 
> Destructors for structs, however, are done the more complicated (and more performant) way because they need to be more efficient.
> 

Thanks for the clarification. This is something I know little about, so I can't argue here.