Scrap your qualified import clutter

Most of the time we find ourselves following this pattern in Haskell:

import Data.Text (Text)
import qualified Data.Text as Text
import Data.ByteString (ByteString)
import qualified Data.ByteString as ByteString

require adds a new keyword that abstracts this. The former code snippet can be reduced to

require Data.Text
require Data.ByteString

Here, the last part of the module is converted to a qualified alias, and a type corresponding to it:

require Data.Text

Will import Data.Text qualified as Text and the Text type.

There are more options, you can check them out in the require docs.

How to use require

• Add require to your project dependencies
• Set the required GHC option:
  • ghc-options: -F -pgmF requirepp in your project configuration file.
  • {-# OPTIONS_GHC -F -pgmF requirepp #-} if you want it per-file.