Haskell Style Guide

style.md

ADT fields should be strict in the general case. This usually reduces memory usage without impacting CPU usage. There are exceptions.

The standard indentation level is 4; indentation should always be done with spaces.

The following ADT definitions are acceptable.

data Foo 
  = Bar Int Int Int
  | Baz String String String
  | Qux Int String

data Post =
  { headline :: Text
  , title :: Text
  , body :: Text
  }

data Maybe a = Just a | Nothing