On 2012-08-23 21:51, Ellery Newcomer wrote:
if I have a member function alias and corresponding object and
arguments, is there any way to turn them into a member function call?
e.g.
class X{
void a();
}
auto profit(alias fn, T, Args...)(T t, Args args) {
???
}
profit!(X.fn, X)(x);
Constraints are:
1) must conserve ability to omit default arguments
2) if x is a subclass of X which overrides a, must not call overriden a.
I have mutually exclusive solutions for (1) and (2).
.. wait, nevermind. I can probably just wrap the two. It's an
interesting problem, though, so I guess I'll post it.
For 1) just parse out the parameter list from typeof(&fn).stringof and
mix it in as profit's arg list, and then just mixin x.a(paramids), but
that won't counter D's virtual functions
For 2) hack together a delegate
dg.ptr = x;
dg.func_ptr = &fn;
but delegates don't support default arguments.
How about this:
import std.stdio;
class Foo
{
auto forward (alias fn, Args...) (Args args)
{
return fn(args);
}
void bar (int a = 3)
{
writeln("bar ", a);
}
}
auto call (alias fn, T, Args...) (T t, Args args)
{
t.forward!(fn)(args);
}
void main ()
{
auto foo = new Foo;
call!(Foo.bar)(foo);
call!(Foo.bar)(foo, 4);
}
Prints:
bar 3
bar 4
Could this work for you?
--
/Jacob Carlborg
