qualified imports, PVP and so on -> check-pvp

[Henning Thielemann]

Am 28.02.2014 21:10, schrieb Henning Thielemann:
> I got distracted by writing a tool that checks consistency of package
> dependencies and import styles. It's not yet perfect, but usable:
>
> https://hackage.haskell.org/package/check-pvp
>
>
> Description:
 > ...
>    The program may complain about an open list of constructors as in
>    .
>    > import Data.Sequence (ViewL(..))
>    .
>    Additions of constructors to @ViewL@ may also conflict with other
> identifiers.

Maybe I am too strict here. The PVP considers additions of constructors 
and class methods as changes, not additions. That is, we don't need to 
fear additions of constructor and methods within the range >=x.y && 
<x.y+1. I may turn this test into "pedantic". I still prefer explicit 
constructor import lists, since they allow the reader to easily track 
the origin of an identifier - especially if it is gone.