{-# LANGUAGE
    FlexibleContexts
  , TypeFamilies
  , UnicodeSyntax
  #-}
-- |FIXME: doc
module Data.Eq.Indirect
    ( Eq'(..)
    , (==:)
    , (/=:)
    , (≡:)
    , (≢:)
    , (≠:)
    )
    where
import Prelude.Unicode

infix 4 ==:{-, /=:, ≡:, ≢:, ≠:-}

-- |FIXME: doc
class Eq (Unified α) ⇒ Eq' α where
    -- |FIXME: doc
    type Unified α
    -- |FIXME: doc
    unify ∷ α → Unified α

-- |FIXME: doc
(==:) ∷ (Eq' α, Eq' β, Unified α ~ Unified β) ⇒ α → β → Bool
{-# INLINE (==:) #-}
(==:) = (∘ unify) ∘ (≡) ∘ unify

-- |FIXME: doc
(/=:) ∷ (Eq' α, Eq' β, Unified α ~ Unified β) ⇒ α → β → Bool
{-# INLINE (/=:) #-}
(/=:) = ((¬) ∘) ∘ (==:)

-- |FIXME: doc
(≡:) ∷ (Eq' α, Eq' β, Unified α ~ Unified β) ⇒ α → β → Bool
{-# INLINE CONLIKE (≡:) #-}
(≡:) = (==:)

-- |FIXME: doc
(≢:) ∷ (Eq' α, Eq' β, Unified α ~ Unified β) ⇒ α → β → Bool
{-# INLINE CONLIKE (≢:) #-}
(≢:) = (/=:)

-- |FIXME: doc
(≠:) ∷ (Eq' α, Eq' β, Unified α ~ Unified β) ⇒ α → β → Bool
{-# INLINE CONLIKE (≠:) #-}
(≠:) = (/=:)