Merge pull request #40 from solomon-b/solomon/semigroupal-infix-opera…

…tors

Adds common Semigroupal infix operators

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Revision history for monoidal-functors
 
 ## Upcoming
+* Adds common infix operators for Semigroupal.
 
 ## 0.2.3.0 -- 2023-08-03
 * Add support for GHC 9.6

src/Data/Bifunctor/Monoidal.hs

@@ -1,6 +1,11 @@
 module Data.Bifunctor.Monoidal
   ( -- * Semigroupal
     Semigroupal (..),
+    (|??|),
+    (|**|),
+    (|++|),
+    (|&&|),
+    (|+*|),
 
     -- * Unital
     Unital (..),
@@ -28,7 +33,7 @@ import Data.Semigroupoid (Semigroupoid (..))
 import Data.These (These (..), these)
 import Data.Tuple (fst, snd, uncurry)
 import Data.Void (Void, absurd)
-import Prelude (Either (..))
+import Prelude (Either (..), curry)
 
 --------------------------------------------------------------------------------
 
@@ -212,6 +217,31 @@ instance Alternative f => Semigroupal (->) (,) Either (,) (Forget (f r)) where
   combine :: (Forget (f r) x y, Forget (f r) x' y') -> Forget (f r) (x, x') (Either y y')
   combine (Forget f, Forget g) = Forget $ \(x, x') -> f x <|> g x'
 
+infixr 9 |??|
+
+(|??|) :: Semigroupal (->) t1 t2 (,) p => p a b -> p a' b' -> p (a `t1` a') (b `t2` b')
+(|??|) = curry combine
+
+infixr 9 |**|
+
+(|**|) :: (Semigroupal (->) (,) (,) (,) p) => p a b -> p a' b' -> p (a, a') (b, b')
+(|**|) = curry combine
+
+infixr 9 |++|
+
+(|++|) :: (Semigroupal (->) Either Either (,) p) => p a b -> p a' b' -> p (Either a a') (Either b b')
+(|++|) = curry combine
+
+infixr 9 |&&|
+
+(|&&|) :: (Semigroupal (->) These These (,) p) => p a b -> p a' b' -> p (These a a') (These b b')
+(|&&|) = curry combine
+
+infixr 9 |+*|
+
+(|+*|) :: (Semigroupal (->) Either (,) (,) p) => p a b -> p a' b' -> p (Either a a') (b, b')
+(|+*|) = curry combine
+
 --------------------------------------------------------------------------------
 
 -- | Given monoidal categories \((\mathcal{C}, \otimes, I_{\mathcal{C}})\) and \((\mathcal{D}, \bullet, I_{\mathcal{D}})\).

src/Data/Functor/Monoidal.hs

@@ -3,11 +3,8 @@ module Data.Functor.Monoidal
     Semigroupal (..),
     (|?|),
     (|*|),
-    type (|*|),
     (|+|),
-    type (|+|),
     (|&|),
-    type (|&|),
 
     -- * Unital
     Unital (..),
@@ -341,12 +338,6 @@ infixr 3 |&|
 (|&|) :: Semigroupal (->) These (,) f => f a -> f b -> f (These a b)
 (|&|) = curry combine
 
-type (|*|) = (,)
-
-type (|+|) = Either
-
-type (|&|) = These
-
 --------------------------------------------------------------------------------
 
 -- | Given monoidal categories \((\mathcal{C}, \otimes, I_{\mathcal{C}})\) and \((\mathcal{D}, \bullet, I_{\mathcal{D}})\).

src/Data/Trifunctor/Monoidal.hs

@@ -1,6 +1,10 @@
 module Data.Trifunctor.Monoidal
   ( -- * Semigroupal
     Semigroupal (..),
+    (|***|),
+    (|*+*|),
+    (|+++|),
+    (|&&&|),
 
     -- * Unital
     Unital (..),
@@ -13,6 +17,8 @@ where
 --------------------------------------------------------------------------------
 
 import Control.Category.Tensor (Associative, Tensor)
+import Prelude (curry, Either)
+import Data.These (These)
 
 --------------------------------------------------------------------------------
 
@@ -49,6 +55,26 @@ class
   -- | A natural transformation \(\phi_{ABC,XYZ} : F\ A\ B\ C \bullet F\ X\ Y\ Z \to F\ (A \otimes X)\ (B \otimes Y) (C \otimes Z)\).
   combine :: to (f x y z) (f x' y' z') `cat` f (t1 x x') (t2 y y') (t3 z z')
 
+infixr 9 |*+*|
+
+(|*+*|) :: (Semigroupal (->) (,) Either (,) (,) p) => p a b c -> p a' b c' -> p (a, a') (Either b b) (c, c')
+(|*+*|) = curry combine
+
+infixr 9 |***|
+
+(|***|) :: (Semigroupal (->) (,) (,) (,) (,) p) => p a b c -> p a' b' c' -> p (a, a') (b, b') (c, c')
+(|***|) = curry combine
+
+infixr 9 |+++|
+
+(|+++|) :: (Semigroupal (->) Either Either Either (,) p) => p a b c -> p a' b' c' -> p (Either a a') (Either b b') (Either c c')
+(|+++|) = curry combine
+
+infixr 9 |&&&|
+
+(|&&&|) :: (Semigroupal (->) These These These (,) p) => p a b c -> p a' b' c' -> p (These a a') (These b b') (These c c')
+(|&&&|) = curry combine
+
 --------------------------------------------------------------------------------
 
 -- | Given monoidal categories \((\mathcal{C}, \otimes, I_{\mathcal{C}})\) and \((\mathcal{D}, \bullet, I_{\mathcal{D}})\).