[Dune] find dune-modules in non-default location with dunecontrol

[Christian Engwer]

Hi Simon,

> # Question
> Now, how do I find this module in a projects that adds this to its
> `dune.module` file, when using dunecontrol? I tried to set the
> `PKG_CONFIG_PATH` manually, but no effect.

this only works, if the module is installed.

> I set in the options file the
> cmake module directory for the module-config.cmake file, but not effect.
> I tried to look into the dunecontrol script to find out how the modules
> are searched, but couldn't determine this corresponding part of the
> script.

No, dunecontrol doesn't ware about the options for tools further up
the chain. Everything is handled by DUNE_CONTROL_PATH. You can add
multiple entries (like in the usual PATH variable) using a colon
separated list. This list can contain directories (which are searched
recursively) and explicitly the dune.module files (which safes some
time, as it avoid long file system seaerches).

Ciao
Christian