I notice imports like

    import qualified Text.PrettyPrint as Disp
          ( Doc, render, char, text )

which seem overly precise to me, when `Disp.` is only used
locally as a module prefix, and there's no other imports sharing
the same module prefix.

Instead, it should suffice to either use

    import qualified Text.PrettyPrint as Disp

or

    import Text.PrettyPrint
          ( Doc, render, char, text )

or in rare cases even

    import Text.PrettyPrint as Disp
          ( Doc, render, char, text )

Hence this relaxes the coding guidelines to allow these simpler forms
to be used.

[skip ci]