enable PerlModules that provide multiple modules

[lexming]

Suggestion for your PR easybuilders#2386

[Flamefire]

In the PR you said e.g. IO:* is part of perl base. How would those be handled with this change?

I wouldn't mind combining both, i.e. allowing string-only items and multiple module names.

However I remember ECs being type-checked. Would this "abuse" of modulename throw this off? @boegel?

[boegel]

It would be better to implement support for modulename being a list of values in EasyBuild framework.

This is hacky at best, since it also does the rest of the sanity check, not just the "import" check...

[lexming]

I targeted the easyblock of PerlModule because this might only be necessary with Perl. I'm not aware of any group of packages in R or Python being distributed in a single source tarball. So the goal is just to emulate single-module virtual extensions and use existing facilities in framework.

If you prefer to have general support for lists in modulename, them that's another story. I'll take a look in framework to see how much work is needed to get that done.

[lexming]

Abandoned. Code will stay available at https://github.com/lexming/easybuild-easyblocks/tree/multi_perlmod