"port provides" inside a Portfile?

[Lawrence Velázquez]

On Apr 5, 2015, at 9:56 PM, Michael Dickens <michaelld at macports.org> wrote:

> Thus, in the new volk Portfile, I need to set up a pre-extract check to
> see if libvolk is already installed, and if so then which port owns it.
> If a gnuradio* port owns it, then I have the Portfile error out, telling
> the user to force deactivate gnuradio*, then issue the upgrade to
> gnuradio* (which will now install volk as well as update gnuradio*).

Sounds like you actually want the deactivate hack.

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

vq