On Wed, Oct 15, 2003 at 03:03:06PM +0200, Lars Gullik Bjønnes wrote:
> Andre Poenitz <[EMAIL PROTECTED]> writes:
>
> | On Wed, Oct 15, 2003 at 01:52:31PM +0200, Lars Gullik Bjønnes wrote:
> >> Free functions should ideally not access class variables,
> >
> | This assumes that the class is not a random collection of individual
> | thing - which it is in our case - but "something real".
>
> then perhaps each of them should be its own singleton?
Or a static variable in a namespace.
*eg*
> >> the functions should be free only when they don't need access to the
> >> class variables and only need the class's public interface for
> >> implementation. (and then of course no class variables should be
> >> public.)
> >
> >> This is the encapsulation part. (or course this can be simulated with
> >> anon namespaces, but then the design is more "open" and access to the
> >> variables are not as controlled.)
> >
> | Handing out non-const refs to members is completely destroying the type
> | of encapsulation you speak of here ("access").
>
> Only in part.
It is _exactly_ the same whether I have a reference to a member of a
singleton or whether I have a reference to some static variable in some
namespace. There is not a wee bit more encapsulation on the class side.
> | The two things are functionality-wise completely equivalent.
>
> >
> | But: In the class solution you have to show private members like
> | 'last_files_' in the .h, whereas in the namespace solution they are
> | hidden in the .C. So this is better encapsulation of the "visibility"
> | type.
>
> The class solution for this is pimpl.
I have been waiting for this one.
We'd better stop now.
Andre'
