empty export warning

[Serge D. Mechveliani]

On Wed, Oct 17, 2007 at 03:35:37PM -0300, Isaac Dupree wrote:
> Serge D. Mechveliani wrote:
> >People, 
> >
> >here is a more precise report about empty _export_ in 
> >ghc-6.8.1-candidate:
> >
> >I use
> >  --------------------------------
> >  module M1 (f, module M2)
> >  where
> >  import M2 ()
> >  f = ...
> >  --------------------------------
> >
> >in the situation when  M1  imports some instances from  M2  and 
> >reexports these instances.
> >
> >And  ghc-6.8.1-candidate  reports 
> >
> >  "Warning: The export item `module M2' exports nothing"
> >
> >1) Can I fix anything here?
> >2) Should this warning be different?
> 
> The warning is true.  The instances will be exported even if `module M2' 
> is omitted from the export list, so that export item exports nothing.
> 


I see. Thank you.

-----------
Mechveliani