>>>>> On Mon, 4 Aug 2014, Michał Górny wrote:
> In particular, I was thinking we could reuse this syntax:

>   || ( A:= B:= )

> to express any-of dependencies that do not support runtime switching
> of providers -- since that is pretty much what := does to slots.
> This would save us from creating a new syntax like '||= ()' [1].

Please don't, because it makes things pretty much unreadable. If you
want an operator like || ( ) but without runtime switching, then
define one (e.g., <<= or ||= as suggested in [1]), but don't try
to inherit properties from its children.

An EAPI bump will be required in any case.

Ulrich

> [1]:https://bugs.gentoo.org/show_bug.cgi?id=489458