qtcurve update failure

[Mojca Miklavec]

On 13 December 2016 at 10:05, René J.V. Bertin wrote:
> Marko Käning wrote on 20161213::06:29:51
>
>>Was easy to fix by uninstalling qtcurve.
>>Yet it would have been nicer to recommend the uninstallation of a too old qtcurve in qtcurve-extra.
>
> This is the kind of situation where you'd want to be able to print a warning at an appropriate time *before* the user starts the upgrade. Or you could halt the upgrade procedure at the opportune moment while the user takes the requested actions. Neither is possible currently.
>
> @macports-devs: for future reference, is there way to automatise the deactivation of an old port? The perl (and p5*) ports are pretty smart during upgrades that I expected to cause this kind of trouble, but they can probably use the `replaced_by` feature, which isn't possible with QtCurve.
>
> I can only think of deleting the files that are to be installed (if they already exist) in a pre-activate block, which should be safe but isn't very elegant.
> I wonder if Debian's packaging scheme doesn't have a trick to indicate files which may already be installed by another package and can be overwritten safely if present.

See:
    https://trac.macports.org/wiki/PortfileRecipes#deactivatehack

Mojca