{-# LANGUAGE CPP #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE Safe #-}
-----------------------------------------------------------------------------
-- |
-- Copyright   :  (C) 2011-2015 Edward Kmett
-- License     :  BSD-style (see the file LICENSE)
--
-- Maintainer  :  Edward Kmett <ekmett@gmail.com>
-- Stability   :  provisional
-- Portability :  portable
--
-- Re-exports a subset of the "Data.Foldable1" module along with some additional
-- combinators that require 'Foldable1' constraints.
--
----------------------------------------------------------------------------
module Data.Semigroup.Foldable
  ( -- @Data.Foldable1@ re-exports
    Foldable1(fold1, foldMap1, toNonEmpty)
  , intercalate1
  , foldrM1
  , foldlM1

    -- Additional @Foldable1@ functionality
  , intercalateMap1
  , traverse1_
  , for1_
  , sequenceA1_
  , foldMapDefault1
  , asum1

    -- Generic defaults
  , gfold1
  , gfoldMap1
  , gtoNonEmpty
  ) where

import Data.Foldable
import Data.Foldable1
import Data.Functor.Alt (Alt(..))
import Data.Functor.Apply
import Data.List.NonEmpty (NonEmpty(..))
import Data.Traversable.Instances ()
import Data.Semigroup hiding (Product, Sum)
import GHC.Generics
import Prelude hiding (foldr)

-- $setup
-- >>> import Data.List.NonEmpty (NonEmpty (..))
-- >>> import Data.Monoid (Monoid (..))

newtype JoinWith a = JoinWith {forall a. JoinWith a -> a -> a
joinee :: (a -> a)}

instance Semigroup a => Semigroup (JoinWith a) where
  JoinWith a -> a
a <> :: JoinWith a -> JoinWith a -> JoinWith a
<> JoinWith a -> a
b = forall a. (a -> a) -> JoinWith a
JoinWith forall a b. (a -> b) -> a -> b
$ \a
j -> a -> a
a a
j forall a. Semigroup a => a -> a -> a
<> a
j forall a. Semigroup a => a -> a -> a
<> a -> a
b a
j

-- | Insert @m@ between each pair of @m@ derived from @a@.
--
-- >>> intercalateMap1 " " show $ True :| [False, True]
-- "True False True"
--
-- >>> intercalateMap1 " " show $ True :| []
-- "True"
intercalateMap1 :: (Foldable1 t, Semigroup m) => m -> (a -> m) -> t a -> m
intercalateMap1 :: forall (t :: * -> *) m a.
(Foldable1 t, Semigroup m) =>
m -> (a -> m) -> t a -> m
intercalateMap1 m
j a -> m
f = forall a b c. (a -> b -> c) -> b -> a -> c
flip forall a. JoinWith a -> a -> a
joinee m
j forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (t :: * -> *) m a.
(Foldable1 t, Semigroup m) =>
(a -> m) -> t a -> m
foldMap1 (forall a. (a -> a) -> JoinWith a
JoinWith forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> b -> a
const forall b c a. (b -> c) -> (a -> b) -> a -> c
. a -> m
f)
{-# INLINE intercalateMap1 #-}

newtype Act f a = Act { forall (f :: * -> *) a. Act f a -> f a
getAct :: f a }

instance Apply f => Semigroup (Act f a) where
  Act f a
a <> :: Act f a -> Act f a -> Act f a
<> Act f a
b = forall (f :: * -> *) a. f a -> Act f a
Act (f a
a forall (f :: * -> *) a b. Apply f => f a -> f b -> f b
.> f a
b)

instance Functor f => Functor (Act f) where
  fmap :: forall a b. (a -> b) -> Act f a -> Act f b
fmap a -> b
f (Act f a
a) = forall (f :: * -> *) a. f a -> Act f a
Act (a -> b
f forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> f a
a)
  a
b <$ :: forall a b. a -> Act f b -> Act f a
<$ Act f b
a = forall (f :: * -> *) a. f a -> Act f a
Act (a
b forall (f :: * -> *) a b. Functor f => a -> f b -> f a
<$ f b
a)

traverse1_ :: (Foldable1 t, Apply f) => (a -> f b) -> t a -> f ()
traverse1_ :: forall (t :: * -> *) (f :: * -> *) a b.
(Foldable1 t, Apply f) =>
(a -> f b) -> t a -> f ()
traverse1_ a -> f b
f t a
t = () forall (f :: * -> *) a b. Functor f => a -> f b -> f a
<$ forall (f :: * -> *) a. Act f a -> f a
getAct (forall (t :: * -> *) m a.
(Foldable1 t, Semigroup m) =>
(a -> m) -> t a -> m
foldMap1 (forall (f :: * -> *) a. f a -> Act f a
Act forall b c a. (b -> c) -> (a -> b) -> a -> c
. a -> f b
f) t a
t)
{-# INLINE traverse1_ #-}

for1_ :: (Foldable1 t, Apply f) => t a -> (a -> f b) -> f ()
for1_ :: forall (t :: * -> *) (f :: * -> *) a b.
(Foldable1 t, Apply f) =>
t a -> (a -> f b) -> f ()
for1_ = forall a b c. (a -> b -> c) -> b -> a -> c
flip forall (t :: * -> *) (f :: * -> *) a b.
(Foldable1 t, Apply f) =>
(a -> f b) -> t a -> f ()
traverse1_
{-# INLINE for1_ #-}

sequenceA1_ :: (Foldable1 t, Apply f) => t (f a) -> f ()
sequenceA1_ :: forall (t :: * -> *) (f :: * -> *) a.
(Foldable1 t, Apply f) =>
t (f a) -> f ()
sequenceA1_ t (f a)
t = () forall (f :: * -> *) a b. Functor f => a -> f b -> f a
<$ forall (f :: * -> *) a. Act f a -> f a
getAct (forall (t :: * -> *) m a.
(Foldable1 t, Semigroup m) =>
(a -> m) -> t a -> m
foldMap1 forall (f :: * -> *) a. f a -> Act f a
Act t (f a)
t)
{-# INLINE sequenceA1_ #-}

-- | Usable default for foldMap, but only if you define foldMap1 yourself
foldMapDefault1 :: (Foldable1 t, Monoid m) => (a -> m) -> t a -> m
foldMapDefault1 :: forall (t :: * -> *) m a.
(Foldable1 t, Monoid m) =>
(a -> m) -> t a -> m
foldMapDefault1 a -> m
f = forall m. WrappedMonoid m -> m
unwrapMonoid forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (t :: * -> *) m a.
(Foldable t, Monoid m) =>
(a -> m) -> t a -> m
foldMap (forall m. m -> WrappedMonoid m
WrapMonoid forall b c a. (b -> c) -> (a -> b) -> a -> c
. a -> m
f)
{-# INLINE foldMapDefault1 #-}

-- toStream :: Foldable1 t => t a -> Stream a
-- concat1 :: Foldable1 t => t (Stream a) -> Stream a
-- concatMap1 :: Foldable1 t => (a -> Stream b) -> t a -> Stream b

newtype Alt_ f a = Alt_ { forall (f :: * -> *) a. Alt_ f a -> f a
getAlt_ :: f a }

instance Alt f => Semigroup (Alt_ f a) where
  Alt_ f a
a <> :: Alt_ f a -> Alt_ f a -> Alt_ f a
<> Alt_ f a
b = forall (f :: * -> *) a. f a -> Alt_ f a
Alt_ (f a
a forall (f :: * -> *) a. Alt f => f a -> f a -> f a
<!> f a
b)

asum1 :: (Foldable1 t, Alt m) => t (m a) -> m a
asum1 :: forall (t :: * -> *) (m :: * -> *) a.
(Foldable1 t, Alt m) =>
t (m a) -> m a
asum1 = forall (f :: * -> *) a. Alt_ f a -> f a
getAlt_ forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall (t :: * -> *) m a.
(Foldable1 t, Semigroup m) =>
(a -> m) -> t a -> m
foldMap1 forall (f :: * -> *) a. f a -> Alt_ f a
Alt_
{-# INLINE asum1 #-}

-- | Generic 'fold1'. Caveats:
--
--   1. Will not compile if @t@ is an empty constructor.
--   2. Will not compile if @t@ has some fields that don't mention @a@, for exmaple @data Bar a = MkBar a Int@
--
-- @since 5.3.8
gfold1 :: (Foldable1 (Rep1 t), Generic1 t, Semigroup m) => t m -> m
gfold1 :: forall (t :: * -> *) m.
(Foldable1 (Rep1 t), Generic1 t, Semigroup m) =>
t m -> m
gfold1 = forall (t :: * -> *) m. (Foldable1 t, Semigroup m) => t m -> m
fold1 forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall k (f :: k -> *) (a :: k). Generic1 f => f a -> Rep1 f a
from1

-- | Generic 'foldMap1'. Caveats are the same as for 'gfold1'.
--
-- @since 5.3.8
gfoldMap1 :: (Foldable1 (Rep1 t), Generic1 t, Semigroup m) => (a -> m) -> t a -> m
gfoldMap1 :: forall (t :: * -> *) m a.
(Foldable1 (Rep1 t), Generic1 t, Semigroup m) =>
(a -> m) -> t a -> m
gfoldMap1 a -> m
f = forall (t :: * -> *) m a.
(Foldable1 t, Semigroup m) =>
(a -> m) -> t a -> m
foldMap1 a -> m
f forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall k (f :: k -> *) (a :: k). Generic1 f => f a -> Rep1 f a
from1

-- | Generic 'toNonEmpty'. Caveats are the same as for 'gfold1'.
--
-- @since 5.3.8
gtoNonEmpty :: (Foldable1 (Rep1 t), Generic1 t) => t a -> NonEmpty a
gtoNonEmpty :: forall (t :: * -> *) a.
(Foldable1 (Rep1 t), Generic1 t) =>
t a -> NonEmpty a
gtoNonEmpty = forall (t :: * -> *) a. Foldable1 t => t a -> NonEmpty a
toNonEmpty forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall k (f :: k -> *) (a :: k). Generic1 f => f a -> Rep1 f a
from1