proposal #2254: have Control.Arrow re-export (>>>) and (<<<)

Niklas Broberg niklas.broberg at
Thu May 1 14:29:55 EDT 2008

>  I'm not sure what the right thing is here.  I usually prefer to avoid
>  re-exports because they create problems with warnings.

I think this is a bit sad actually. The situation discussed here is
(IMO) exactly the kind of situation that re-exports are intended for.
That some tools give warnings for re-exports is a flaw in those tools,
not a problem with the re-export per se.

Generally, if module A exports foo, module B imports A and re-exports
foo, and module C imports both A and B, there should be no ambiguity.
Not even if it reexports all of modules A and B. Why would e.g. GHC
need to warn in that case?



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