[Modules] Disable implicitly requirements

[Leo B. <leo...@gm...>]

Hello,

I've recently compiled modules 4.2.3 and I'm testing with my existing
modulefiles. I can't tell what my existing version is (at least, I don't
see any way to report the version), but it's at least five years old.

Something the new version does that I would like to disable is to create
implicit requirements from modulefiles loaded inside a modulefile that then
causes an error during module switch commands.

For example, if I have a modulefile "parent" with two module load
statements in it:

module load fred/1.3
module load barney/2.1

I'll see this displayed when I load the parent module:

  Loading requirement: fred/1.3 barney/2.1

Then I want to switch to a different version of barney for testing.

% module switch barney/2.2
Unloading barney/2.1
  ERROR: barney/2.1 cannot be unloaded due to a prereq.
    HINT: Might try "module unload parent" first.

I have no prereq statements, so it must be getting implicitly inferred at
the time the parent module is loaded. I need to load a default set of
specific versions of tools but users need to be able to swap them out later.

I think when I tested 4.2.1 I was able to do the module switch, but I
couldn't then do "module unload parent" as it would lead to a similar
message as above.

Is there a way to simple way to disable this? I've been looking through the
docs but I haven't hit upon it yet.

Thanks,

- Leo