Re: [Vala] Ownership syntax changes

[Jürg Billeter <j bitron ch>]

On Sat, 2008-12-20 at 12:19 +0100, Xavier Bestel wrote:
> Le vendredi 19 décembre 2008 à 12:10 +0100, Jürg Billeter a écrit :
> > I just committed some ownership syntax changes to trunk. The old syntax
> > will continue to be supported but is planned to be deprecated after the
> > release of Vala 0.5.4.
> >
> >
> >       * `owned' type modifier replaces `#' type modifier
> >
> > This is not often used, but `#' was very unintuitive as a type modifier,
> > and I therefore decided to replace it by the hopefully better
> > understandable `owned' modifier. Example of new syntax:
> >
> > public void foo (owned string bar) {
> >     [...]
> > }
>
> I like the idea, but the word "owned" doesn't really tells by who it's
> owned (caller or callee). How about something like "callers" or
> "transfer" ?

`owned' applied to a parameter means that the parameter owns the object,
that is, the ownership of the object is transferred in the same
direction as the parameter value: to the callee for input paramters, to
the caller for output parameters, and input to the callee and output to
the caller for `ref' parameters.

The issue with the caller/callee owned terminology is that this does not
apply very well to `ref' parameters and fields, which means that we
would need yet another modifier in those places.

Jürg