-----------------------------------------------------------------------------
-- |
-- Module      :  Data.Pid
-- Copyright   :  (c) 2020-2021 EMQ Technologies Co., Ltd.
-- License     :  BSD-style (see the LICENSE file)
--
-- Maintainer  :  Feng Lee, feng@emqx.io
--                Yang M, yangm@emqx.io
-- Stability   :  experimental
-- Portability :  portable
--
-- The Erlang Pid datatype.
--
-----------------------------------------------------------------------------
module Data.Pid (Pid) where

import Data.Eq (class Eq)
import Data.Ord
  ( class Ord
  , Ordering(..)
  )
import Data.Show (class Show)

-- | Erlang process identifier.
foreign import data Pid :: Type

instance Eq Pid where
  eq = eqPidImpl

instance Ord Pid where
  compare = cmpPidImpl LT EQ GT

instance Show Pid where
  show = showPidImpl

foreign import eqPidImpl :: Pid -> Pid -> Boolean

foreign import cmpPidImpl
  :: Ordering
  -> Ordering
  -> Ordering
  -> Pid
  -> Pid
  -> Ordering

foreign import showPidImpl :: Pid -> String