{-# LANGUAGE NoImplicitPrelude #-} {-# LANGUAGE FlexibleInstances #-} module Data.Aviation.Units.Millimetres( Millimetres(millimetres) ) where import Control.Category(id) import Control.Lens(Iso') import Prelude(Rational) class Millimetres a where millimetres :: Iso' Rational a instance Millimetres Rational where millimetres :: p Rational (f Rational) -> p Rational (f Rational) millimetres = p Rational (f Rational) -> p Rational (f Rational) forall k (cat :: k -> k -> *) (a :: k). Category cat => cat a a id