{-# LANGUAGE NoImplicitPrelude, UnicodeSyntax #-}

{-|
Module     : PreludePlus.Unicode
Copyright  : 2018 Joshua Booth
License    : BSD3 (see the file LICENSE)
Maintainer : Joshua Booth <joshua.n.booth@gmail.com>

Various unicode synonyms for basic functions.
-}

module PreludePlus.Unicode
    ( -- * Functional
      (∘)
    , (↦)
    , (↤)
    , (↤∘)
    , (≫=)
    , (≫)
    , (=≪)
    -- * Boolean
    , (∨)
    , (∧)
    -- * Comparison
    , (≡)
    , (≠)
    , (≤)
    , (≥)
    -- * Arithmetic
    , (÷)
    , (٪)
    , (—)
    -- * Collections
    , (∈)
    , (∉)
    , (⧺)
    , (∪)
    , (∩)
    , (⩀)
    , ø
    ) where

import Control.Monad  (Monad, (>>=), (>>), (=<<))
import Data.Bool      (Bool, (&&), (||), not)
import Data.Eq        (Eq, (==), (/=))
import Data.Foldable  (Foldable, elem, notElem)
import Data.Function  ((.), ($), flip)
import Data.Functor   (Functor, fmap)
import Data.Monoid    (Monoid, (<>), mempty)
import Data.List      (intersect, null, union)
import Data.Ord       (Ord, (<=), (>=))
import Data.Semigroup (Semigroup)
import GHC.Num        (Num, (-))
import GHC.Real       (Integral, quot, mod)

------------
-- Functions
------------

-- | '.'
infixr 9 ∘
(∘) ∷ (b → g) → (a → b) → (a → g)
(∘) = (.)
{-# INLINE (∘) #-}

-- | 'flip' . 'fmap'
infixl 6 ↦
(↦) ∷ Functor f ⇒ f a → (a → b) → f b
(↦) = flip fmap
{-# INLINE (↦) #-}

-- | 'fmap'
infixl 6 ↤
(↤) ∷ Functor f ⇒ (a → b) → f a → f b
(↤) = fmap
{-# INLINE (↤) #-}

-- | 'fmap' '.'
infixr 7 ↤∘
(↤∘) ∷ Functor f ⇒ (a → b) → (c → f a) → c → f b
f ↤∘ g = fmap f ∘ g

-- | '>>='
infixl 1 ≫=
(≫=) ∷ Monad m ⇒ m a → (a → m b) → m b
(≫=) = (>>=)
{-# INLINE (≫=) #-}

-- | '>>'
infixl 1 ≫
(≫) ∷ Monad m ⇒ m a → m b → m b
(≫) = (>>)
{-# INLINE (≫) #-}

-- | '=<<'
infixr 1 =≪
(=≪) ∷ Monad m ⇒ (a → m b) → m a → m b
(=≪) = (=<<)
{-# INLINE (=≪) #-}

----------
-- Boolean
----------

-- | '&&'
infixr 2 ∨
(∨) ∷ Bool → Bool → Bool
(∨) = (||)
{-# INLINE (∨) #-}

-- | '||'
infixr 3 ∧
(∧) ∷ Bool → Bool → Bool
(∧) = (&&)
{-# INLINE (∧) #-}

-------------
-- Comparison
-------------

-- | '=='
infix  4 ≡
(≡) ∷ Eq a ⇒ a → a → Bool
(≡) = (==)
{-# INLINE (≡) #-}

-- | '≠'
infix  4 ≠
(≠) ∷ Eq a ⇒ a → a → Bool
(≠) = (/=)
{-# INLINE (≠) #-}

-- | '<='
infix  4 ≤
(≤) ∷ Ord a ⇒ a → a → Bool
(≤) = (<=)
{-# INLINE (≤) #-}

-- | '>='
infix  4 ≥
(≥) ∷ Ord a ⇒ a → a → Bool
(≥) = (>=)
{-# INLINE (≥) #-}

-------------
-- Arithmetic
-------------

-- | 'quot'
infixl 7 ÷
(÷) ∷ Integral a ⇒ a → a → a
(÷) = quot
{-# INLINE (÷) #-}

-- | 'mod'
infixl 7 ٪
(٪) ∷ Integral a ⇒ a → a → a
(٪) = mod
{-# INLINE (٪) #-}

-- | '-' allowing for sections
(—) ∷ Num a ⇒ a → a → a
(—) = (-) 

--------------
-- Collections
--------------

-- | 'elem'
infix  4 ∈
(∈) ∷ (Foldable a, Eq b) ⇒ b → a b → Bool
(∈) = elem
{-# INLINE (∈) #-}

-- | 'notElem'
infix 4 ∉
(∉) ∷ (Foldable a, Eq b) ⇒ b → a b → Bool
(∉) = notElem
{-# INLINE (∉) #-}

-- | '<>'
infixr 5 ⧺
(⧺) ∷ Semigroup m ⇒ m → m → m
(⧺) = (<>)
{-# INLINE (⧺) #-}

-- | 'union'
infixl 6 ∪
(∪) ∷ Eq a ⇒ [a] → [a] → [a]
(∪) = union
{-# INLINE (∪) #-}

-- | 'intersect'
infixr 6 ∩
(∩) ∷ Eq a ⇒ [a] → [a] → [a]
(∩) = intersect

-- | 'not' '.' 'null' '.' 'intersect'
infixr 6 ⩀
(⩀) ∷ Eq a ⇒ [a] → [a] → Bool
(⩀) a b = not ∘ null $ intersect a b

-- | 'mempty'
ø ∷ Monoid a ⇒ a
ø = mempty