thomasw authored Jul 23, 2015 and Ben Gamari committed Jul 23, 2015

When a constructor was mistakenly imported directly instead of as a
constructor of a data type, a hint will be shown on how to correctly
import
it. Just like the constructor, the data type should be surrounded in
parentheses if it is an operator (TypeOperator in this case).

Instead of:

    error:
        In module ‘Data.Type.Equality’:
          ‘Refl’ is a data constructor of ‘:~:’
        To import it use
          ‘import’ Data.Type.Equality( :~:( Refl ) )
        or
          ‘import’ Data.Type.Equality( :~:(..) )

Print:

    error:
        In module ‘Data.Type.Equality’:
          ‘Refl’ is a data constructor of ‘(:~:)’
        To import it use
          ‘import’ Data.Type.Equality( (:~:)( Refl ) )
        or
          ‘import’ Data.Type.Equality( (:~:)(..) )

Test Plan: pass new test

Reviewers: austin, bgamari, simonpj

Reviewed By: simonpj

Subscribers: simonpj, thomie

Differential Revision: https://phabricator.haskell.org/D1093

GHC Trac Issues: #10668