Excerpts from Lee, Alexis's message of 2014-11-05 15:46:43 +0100:
> I'm considering adding a function which takes a list and returns the first
> non-null, non-empty value in that list.
>
> So you could do EG:
>
> some_thing:
> config:
> ControlVIP:
> first_nonnull:
> - {get_param: ControlVIP}
> - {get_attr: [ControlVirtualIP, fixed_ips, 0, ip_address]}]}
>
> I'm open to other names, EG "some", "or", "fallback_list" etc.
>
> Steve Hardy suggested building this into get_attr or Fn::Select. My feeling
> is that those each do one job well right now, I'm happy to take a steer
> though.
>
> What do you think please?
>
Yes this is super useful for writing responsive, reusable templates.
I'd like to suggest that this be called 'coalesce' as that is what SQL
calls it.
_______________________________________________
OpenStack-dev mailing list
OpenStack-dev@lists.openstack.org
http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
