UnusedDctorExplicitImport Warning

Example

module ShortFailingExample where

import Data.Maybe (Maybe(Just, Nothing))

test = Nothing

Cause

A module is imported with an explicit imports list including a type with an explicit list of data construtors (Maybe(Just,Nothing) in this example) but some of the mentioned data constructors are unused.

Fix

Import only the used data constructors:

import Data.Maybe (Maybe(Nothing))

Alternatively import all data constructors non-explicitly:

import Data.Maybe (Maybe(..))

Notes

This error is auto-fixable.