Re: ADL woes

Kimon Hoffmann ha scritto:
> 
> It is obvious why the cool_algorithm_X() functions choke when calling 
> func() with a constant NotWorking reference

Well, what you say it's correct, but it is not *that* obvious. Function
default_impl::func(NotWorking):

1) is not found in binding phase 1 because it is not visible at the
point of definition of the template. (Had it been visible at that point,
the program would compile nicely regardless of the fact that NotWorking
is in the "wrong" namespace.)

2) is not found in binding phase 2 because in neither cases ADL is
triggered (in the first case because default_impl is not an associated
namespace of NotWorking and in the second case because of the full
qualification)

> and it is also clear to me 
> why the correct overload of func() is found from within 
> cool_algorithm_1() in the HalfWorking case.

Correct, that's because in that case ADL kicks in and the global
namespace is an associated namespace of HalfWorking, so the function is
found in binding phase 2.

> What I'd like to know is whether there is some way to make HalfWorking 
> work with fully qualified calls to func() like the one in 
> cool_algorithm_2(), besides the obvious solution to move HalfWorking 
> together with the function overload into the default_impl namespace.

Given that the target function is not defined in namespace default_impl,
I don't see how you might refer to it with a name fully qualified with
default_impl::.

HTH,

Ganesh

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