no clue if conflicting module unload was attempted when raising conflict issue

[xdelaruelle]

Taking following modules as example:

$ module show mb mc me mf
-------------------------------------------------------------------
/path/to/modulefiles/mb:

module          load mc
-------------------------------------------------------------------
/path/to/modulefiles/mc:

module          unload mc
-------------------------------------------------------------------
/path/to/modulefiles/me:

module          load mb
module          load mf
-------------------------------------------------------------------
/path/to/modulefiles/mf:

module          unload mc
-------------------------------------------------------------------

When loading me, its requirements express conflicting needs. mc is first loaded by mb then mf attempts to remove it. However failing automated unload of mc is not reported and a confusing message suggesting the unload should be done is returned:

$ module load me
Unloading mc
  ERROR: mc cannot be unloaded due to a prereq.
    HINT: Might try "module unload mb" first.

Loading mf
  ERROR: mf cannot be loaded due to a conflict.
    HINT: Might try "module unload mc" first.

Loading me
  ERROR: me cannot be loaded due to missing prereq.
    HINT: the following module must be loaded first: mf