How to disable warning for "export item 'module ...' exports nothing"?

Ross Paterson ross at
Fri Aug 15 08:51:12 EDT 2008

On Fri, Aug 15, 2008 at 02:21:33PM +0200, Sean Leather wrote:
> In my case, it does matter where instances are in scope. My library
> requires orphan instances by design. If the programmer imports the
> top-level module, then s/he gets a default set of instances. But the
> programmer has the option to import select modules and get a different
> set of classes and instances.

With implicit import, it just doesn't work to have different instances in
different places.  Suppose two modules use your library in the different
ways you envisage.  Then those modules cannot be used together in the
same program.  Your library will not be re-usable.

I'd recommend seeking alternate forms of parameterization.

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