From a6b95556c3593c2cdb4047f59fada1aa5d62a068 Mon Sep 17 00:00:00 2001
From: M Farkas-Dyck <strake888@gmail.com>
Date: Wed, 27 Sep 2017 13:21:54 -0800
Subject: [PATCH 1/7] make `Map` not associated to class; it needn't be

---
 Data/OpenRecords.hs | 40 ++++++++++++++++++----------------------
 1 file changed, 18 insertions(+), 22 deletions(-)

diff --git a/Data/OpenRecords.hs b/Data/OpenRecords.hs
index b130b9a..916babe 100644
--- a/Data/OpenRecords.hs
+++ b/Data/OpenRecords.hs
@@ -374,51 +374,47 @@ class Forall (r :: Row *) (c :: * -> Constraint) where
 labels :: forall r s . (Forall r Unconstrained1, IsString s) => Proxy r -> [s]
 labels _ = getConst $ rinitAWithLabel @r (Proxy @Unconstrained1) (Const . pure . show')
 
-class RowMap (f :: * -> *) (r :: Row *) where
-  type Map f r :: Row *
+type family Map (f :: a -> b) (r :: Row a) :: Row b where Map f (R r) = R (RM f r)
+
+class RowMap (r :: Row *) where
   rmap :: Proxy f -> (forall a.  a -> f a) -> Rec r -> Rec (Map f r)
   rsequence :: Applicative f => Proxy f -> Rec (Map f r) -> f (Rec r)
 
-instance RowMapx f r => RowMap f (R r) where
-  type Map f (R r) = R (RM f r)
+instance RowMapx r => RowMap (R r) where
   rmap = rmap'
   rsequence = rsequence'
 
-class RowMapx (f :: * -> *) (r :: [LT *]) where
-  type RM f r :: [LT *]
+type family RM (f :: a -> b) (r :: [LT a]) :: [LT b] where
+  RM f '[] = '[]
+  RM f (l :-> v ': t) = l :-> f v ': RM f t
+
+class RowMapx (r :: [LT *]) where
   rmap' :: Proxy f -> (forall a.  a -> f a) -> Rec (R r) -> Rec (R (RM f r))
   rsequence' :: Applicative f => Proxy f -> Rec (R (RM f r)) -> f (Rec (R r))
 
-instance RowMapx f '[] where
-  type RM f '[] = '[]
+instance RowMapx '[] where
   rmap' _ _ _ = empty
   rsequence' _ _ = pure empty
 
-instance (KnownSymbol l,  RowMapx f t) => RowMapx f (l :-> v ': t) where
-  type RM f (l :-> v ': t) = l :-> f v ': RM f t
+instance (KnownSymbol l,  RowMapx t) => RowMapx (l :-> v ': t) where
   rmap' w f r = unsafeInjectFront l (f (r .! l)) (rmap' w f (r .- l))
     where l = Label :: Label l
   rsequence' w r = unsafeInjectFront l <$> r .! l <*> rsequence' w (r .- l)
     where l = Label :: Label l
 
-class RowMapC (c :: * -> Constraint) (f :: * -> *) (r :: Row *) where
-  type MapC c f r :: Row *
-  rmapc :: Proxy c -> Proxy f -> (forall a. c a => a -> f a) -> Rec r -> Rec (MapC c f r)
+class RowMapC (c :: * -> Constraint) (r :: Row *) where
+  rmapc :: Proxy c -> Proxy f -> (forall a. c a => a -> f a) -> Rec r -> Rec (Map f r)
 
-instance RMapc c f r => RowMapC c f (R r) where
-  type MapC c f (R r) = R (RMapp c f r)
+instance RMapc c r => RowMapC c (R r) where
   rmapc = rmapc'
 
-class RMapc (c :: * -> Constraint) (f :: * -> *) (r :: [LT *]) where
-  type RMapp c f r :: [LT *]
-  rmapc' :: Proxy c -> Proxy f -> (forall a. c a => a -> f a) -> Rec (R r) -> Rec (R (RMapp c f r))
+class RMapc (c :: * -> Constraint) (r :: [LT *]) where
+  rmapc' :: Proxy c -> Proxy f -> (forall a. c a => a -> f a) -> Rec (R r) -> Rec (R (RM f r))
 
-instance RMapc c f '[] where
-  type RMapp c f '[] = '[]
+instance RMapc c '[] where
   rmapc' _ _ _ _ = empty
 
-instance (KnownSymbol l, c v, RMapc c f t) => RMapc c f (l :-> v ': t) where
-  type RMapp c f (l :-> v ': t) = l :-> f v ': RMapp c f t
+instance (KnownSymbol l, c v, RMapc c t) => RMapc c (l :-> v ': t) where
   rmapc' c w f r = unsafeInjectFront l (f (r .! l)) (rmapc' c w f (r .- l))
     where l = Label :: Label l
 

From 3f6a18f8a7bdb7b79b02181a5efdd0799c085d3b Mon Sep 17 00:00:00 2001
From: M Farkas-Dyck <strake888@gmail.com>
Date: Mon, 2 Oct 2017 11:17:55 -0800
Subject: [PATCH 2/7] move `rmapc` into `Forall`

---
 Data/OpenRecords.hs | 22 ++++++----------------
 1 file changed, 6 insertions(+), 16 deletions(-)

diff --git a/Data/OpenRecords.hs b/Data/OpenRecords.hs
index 916babe..58c1ded 100644
--- a/Data/OpenRecords.hs
+++ b/Data/OpenRecords.hs
@@ -371,6 +371,8 @@ class Forall (r :: Row *) (c :: * -> Constraint) where
   -- with the same label and collect the result in a list.
   eraseZip :: Proxy c -> (forall a. c a => a -> a -> b) -> Rec r -> Rec r -> [b]
 
+  rmapc :: Proxy c -> Proxy f -> (forall a. c a => a -> f a) -> Rec r -> Rec (Map f r)
+
 labels :: forall r s . (Forall r Unconstrained1, IsString s) => Proxy r -> [s]
 labels _ = getConst $ rinitAWithLabel @r (Proxy @Unconstrained1) (Const . pure . show')
 
@@ -402,28 +404,13 @@ instance (KnownSymbol l,  RowMapx t) => RowMapx (l :-> v ': t) where
   rsequence' w r = unsafeInjectFront l <$> r .! l <*> rsequence' w (r .- l)
     where l = Label :: Label l
 
-class RowMapC (c :: * -> Constraint) (r :: Row *) where
-  rmapc :: Proxy c -> Proxy f -> (forall a. c a => a -> f a) -> Rec r -> Rec (Map f r)
-
-instance RMapc c r => RowMapC c (R r) where
-  rmapc = rmapc'
-
-class RMapc (c :: * -> Constraint) (r :: [LT *]) where
-  rmapc' :: Proxy c -> Proxy f -> (forall a. c a => a -> f a) -> Rec (R r) -> Rec (R (RM f r))
-
-instance RMapc c '[] where
-  rmapc' _ _ _ _ = empty
-
-instance (KnownSymbol l, c v, RMapc c t) => RMapc c (l :-> v ': t) where
-  rmapc' c w f r = unsafeInjectFront l (f (r .! l)) (rmapc' c w f (r .- l))
-    where l = Label :: Label l
-
 instance Forall (R '[]) c where
   rinit _ _ = empty
   rinitAWithLabel _ _ = pure empty
   eraseWithLabels _ _ _ = []
   eraseToHashMap _ _ _ = M.empty
   eraseZip _ _ _ _ = []
+  rmapc _ _ _ _ = empty
 
 instance (KnownSymbol l, Forall (R t) c, c a) => Forall (R (l :-> a ': t)) c where
   rinit c f = unsafeInjectFront l f (rinit c f) where l = Label :: Label l
@@ -439,6 +426,9 @@ instance (KnownSymbol l, Forall (R t) c, c a) => Forall (R (l :-> a ': t)) c whe
   eraseZip c f x y = f (x .! l) (y .! l) : eraseZip c f (x .- l) (y .- l) where
     l = Label :: Label l
 
+  rmapc c w f r = unsafeInjectFront l (f (r .! l)) (rmapc c w f (r .- l))
+    where l = Label :: Label l
+
 show' :: (IsString s, Show a) => a -> s
 show' = fromString . show
 

From 22ba8611a5701fe7ea8c4ada952c13de3bc94992 Mon Sep 17 00:00:00 2001
From: M Farkas-Dyck <strake888@gmail.com>
Date: Mon, 2 Oct 2017 11:31:08 -0800
Subject: [PATCH 3/7] delete some unneeded `Proxy` parametres

---
 CTRex.cabal         |  3 ++-
 Data/OpenRecords.hs | 23 ++++++++++++-----------
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/CTRex.cabal b/CTRex.cabal
index a09e88f..2dd1d21 100644
--- a/CTRex.cabal
+++ b/CTRex.cabal
@@ -39,7 +39,8 @@ Library
               TypeFamilies,
               TypeOperators,
               ViewPatterns,
-              UndecidableInstances
+              UndecidableInstances,
+              UnicodeSyntax
 
 source-repository head
     type:     git
diff --git a/Data/OpenRecords.hs b/Data/OpenRecords.hs
index 58c1ded..69476f9 100644
--- a/Data/OpenRecords.hs
+++ b/Data/OpenRecords.hs
@@ -371,7 +371,7 @@ class Forall (r :: Row *) (c :: * -> Constraint) where
   -- with the same label and collect the result in a list.
   eraseZip :: Proxy c -> (forall a. c a => a -> a -> b) -> Rec r -> Rec r -> [b]
 
-  rmapc :: Proxy c -> Proxy f -> (forall a. c a => a -> f a) -> Rec r -> Rec (Map f r)
+  rmapc :: Proxy c -> (forall a. c a => a -> f a) -> Rec r -> Rec (Map f r)
 
 labels :: forall r s . (Forall r Unconstrained1, IsString s) => Proxy r -> [s]
 labels _ = getConst $ rinitAWithLabel @r (Proxy @Unconstrained1) (Const . pure . show')
@@ -379,8 +379,8 @@ labels _ = getConst $ rinitAWithLabel @r (Proxy @Unconstrained1) (Const . pure .
 type family Map (f :: a -> b) (r :: Row a) :: Row b where Map f (R r) = R (RM f r)
 
 class RowMap (r :: Row *) where
-  rmap :: Proxy f -> (forall a.  a -> f a) -> Rec r -> Rec (Map f r)
-  rsequence :: Applicative f => Proxy f -> Rec (Map f r) -> f (Rec r)
+  rmap :: (forall a. a -> f a) -> Rec r -> Rec (Map f r)
+  rsequence :: Applicative f => Rec (Map f r) -> f (Rec r)
 
 instance RowMapx r => RowMap (R r) where
   rmap = rmap'
@@ -391,17 +391,17 @@ type family RM (f :: a -> b) (r :: [LT a]) :: [LT b] where
   RM f (l :-> v ': t) = l :-> f v ': RM f t
 
 class RowMapx (r :: [LT *]) where
-  rmap' :: Proxy f -> (forall a.  a -> f a) -> Rec (R r) -> Rec (R (RM f r))
-  rsequence' :: Applicative f => Proxy f -> Rec (R (RM f r)) -> f (Rec (R r))
+  rmap' :: (forall a. a -> f a) -> Rec (R r) -> Rec (R (RM f r))
+  rsequence' :: Applicative f => Rec (R (RM f r)) -> f (Rec (R r))
 
 instance RowMapx '[] where
-  rmap' _ _ _ = empty
-  rsequence' _ _ = pure empty
+  rmap' _ _ = empty
+  rsequence' _ = pure empty
 
 instance (KnownSymbol l,  RowMapx t) => RowMapx (l :-> v ': t) where
-  rmap' w f r = unsafeInjectFront l (f (r .! l)) (rmap' w f (r .- l))
+  rmap' f r = unsafeInjectFront l (f (r .! l)) (rmap' f (r .- l))
     where l = Label :: Label l
-  rsequence' w r = unsafeInjectFront l <$> r .! l <*> rsequence' w (r .- l)
+  rsequence' r = unsafeInjectFront l <$> r .! l <*> rsequence' (r .- l)
     where l = Label :: Label l
 
 instance Forall (R '[]) c where
@@ -410,7 +410,7 @@ instance Forall (R '[]) c where
   eraseWithLabels _ _ _ = []
   eraseToHashMap _ _ _ = M.empty
   eraseZip _ _ _ _ = []
-  rmapc _ _ _ _ = empty
+  rmapc _ _ _ = empty
 
 instance (KnownSymbol l, Forall (R t) c, c a) => Forall (R (l :-> a ': t)) c where
   rinit c f = unsafeInjectFront l f (rinit c f) where l = Label :: Label l
@@ -426,7 +426,8 @@ instance (KnownSymbol l, Forall (R t) c, c a) => Forall (R (l :-> a ': t)) c whe
   eraseZip c f x y = f (x .! l) (y .! l) : eraseZip c f (x .- l) (y .- l) where
     l = Label :: Label l
 
-  rmapc c w f r = unsafeInjectFront l (f (r .! l)) (rmapc c w f (r .- l))
+  rmapc :: ∀ f . Proxy c -> (forall a. c a => a -> f a) -> Rec (R (l :-> a ': t)) -> Rec (Map f (R (l :-> a ': t)))
+  rmapc c f r = unsafeInjectFront l (f (r .! l)) (rmapc @_ @_ @f c f (r .- l))
     where l = Label :: Label l
 
 show' :: (IsString s, Show a) => a -> s

From 388c907a0a91af2cf6839f58727e389bd3551c3e Mon Sep 17 00:00:00 2001
From: M Farkas-Dyck <strake888@gmail.com>
Date: Mon, 2 Oct 2017 11:38:44 -0800
Subject: [PATCH 4/7] export `Map`, `RowMap`

---
 Data/OpenRecords.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Data/OpenRecords.hs b/Data/OpenRecords.hs
index 69476f9..34ee13f 100644
--- a/Data/OpenRecords.hs
+++ b/Data/OpenRecords.hs
@@ -50,6 +50,7 @@ module Data.OpenRecords
              -- * Row constraints
              (:\), Disjoint, Labels, Forall(..),
              -- * Row only operations
+             Map, RowMap (..),
              -- * Syntactic sugar
              RecOp(..), RowOp(..), (.|), (:|),
              -- * Labels

From 5105151cf5bba571a55395338db40545e613bc1b Mon Sep 17 00:00:00 2001
From: M Farkas-Dyck <strake888@gmail.com>
Date: Mon, 2 Oct 2017 13:39:00 -0800
Subject: [PATCH 5/7] export `RowZip`

---
 Data/OpenRecords.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Data/OpenRecords.hs b/Data/OpenRecords.hs
index 34ee13f..a4991a4 100644
--- a/Data/OpenRecords.hs
+++ b/Data/OpenRecords.hs
@@ -50,7 +50,7 @@ module Data.OpenRecords
              -- * Row constraints
              (:\), Disjoint, Labels, Forall(..),
              -- * Row only operations
-             Map, RowMap (..),
+             Map, RowMap (..), RowZip (..),
              -- * Syntactic sugar
              RecOp(..), RowOp(..), (.|), (:|),
              -- * Labels

From e303d1bbdc0316541202f4daa7b7d3f81a2b3fd4 Mon Sep 17 00:00:00 2001
From: M Farkas-Dyck <strake888@gmail.com>
Date: Mon, 2 Oct 2017 12:24:18 -0800
Subject: [PATCH 6/7] unmethodize `rmap`

---
 Data/OpenRecords.hs | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/Data/OpenRecords.hs b/Data/OpenRecords.hs
index a4991a4..98d4cef 100644
--- a/Data/OpenRecords.hs
+++ b/Data/OpenRecords.hs
@@ -50,7 +50,7 @@ module Data.OpenRecords
              -- * Row constraints
              (:\), Disjoint, Labels, Forall(..),
              -- * Row only operations
-             Map, RowMap (..), RowZip (..),
+             Map, RowMap (..), RowZip (..), rmap,
              -- * Syntactic sugar
              RecOp(..), RowOp(..), (.|), (:|),
              -- * Labels
@@ -377,14 +377,15 @@ class Forall (r :: Row *) (c :: * -> Constraint) where
 labels :: forall r s . (Forall r Unconstrained1, IsString s) => Proxy r -> [s]
 labels _ = getConst $ rinitAWithLabel @r (Proxy @Unconstrained1) (Const . pure . show')
 
+rmap :: Forall r Unconstrained1 => (forall a. a -> f a) -> Rec r -> Rec (Map f r)
+rmap = rmapc (Proxy @Unconstrained1)
+
 type family Map (f :: a -> b) (r :: Row a) :: Row b where Map f (R r) = R (RM f r)
 
 class RowMap (r :: Row *) where
-  rmap :: (forall a. a -> f a) -> Rec r -> Rec (Map f r)
   rsequence :: Applicative f => Rec (Map f r) -> f (Rec r)
 
 instance RowMapx r => RowMap (R r) where
-  rmap = rmap'
   rsequence = rsequence'
 
 type family RM (f :: a -> b) (r :: [LT a]) :: [LT b] where
@@ -392,16 +393,12 @@ type family RM (f :: a -> b) (r :: [LT a]) :: [LT b] where
   RM f (l :-> v ': t) = l :-> f v ': RM f t
 
 class RowMapx (r :: [LT *]) where
-  rmap' :: (forall a. a -> f a) -> Rec (R r) -> Rec (R (RM f r))
   rsequence' :: Applicative f => Rec (R (RM f r)) -> f (Rec (R r))
 
 instance RowMapx '[] where
-  rmap' _ _ = empty
   rsequence' _ = pure empty
 
 instance (KnownSymbol l,  RowMapx t) => RowMapx (l :-> v ': t) where
-  rmap' f r = unsafeInjectFront l (f (r .! l)) (rmap' f (r .- l))
-    where l = Label :: Label l
   rsequence' r = unsafeInjectFront l <$> r .! l <*> rsequence' (r .- l)
     where l = Label :: Label l
 

From 55abb439469482dfe396a509a22ed5e83f7a8241 Mon Sep 17 00:00:00 2001
From: M Farkas-Dyck <strake888@gmail.com>
Date: Mon, 2 Oct 2017 12:31:08 -0800
Subject: [PATCH 7/7] define `rxform`

---
 Data/OpenRecords.hs | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/Data/OpenRecords.hs b/Data/OpenRecords.hs
index 98d4cef..416513d 100644
--- a/Data/OpenRecords.hs
+++ b/Data/OpenRecords.hs
@@ -50,7 +50,7 @@ module Data.OpenRecords
              -- * Row constraints
              (:\), Disjoint, Labels, Forall(..),
              -- * Row only operations
-             Map, RowMap (..), RowZip (..), rmap,
+             Map, RowMap (..), RowZip (..), rmap, rxform,
              -- * Syntactic sugar
              RecOp(..), RowOp(..), (.|), (:|),
              -- * Labels
@@ -373,6 +373,7 @@ class Forall (r :: Row *) (c :: * -> Constraint) where
   eraseZip :: Proxy c -> (forall a. c a => a -> a -> b) -> Rec r -> Rec r -> [b]
 
   rmapc :: Proxy c -> (forall a. c a => a -> f a) -> Rec r -> Rec (Map f r)
+  rxformc :: Proxy c -> (forall a. c a => f a -> g a) -> Rec (Map f r) -> Rec (Map g r)
 
 labels :: forall r s . (Forall r Unconstrained1, IsString s) => Proxy r -> [s]
 labels _ = getConst $ rinitAWithLabel @r (Proxy @Unconstrained1) (Const . pure . show')
@@ -380,6 +381,9 @@ labels _ = getConst $ rinitAWithLabel @r (Proxy @Unconstrained1) (Const . pure .
 rmap :: Forall r Unconstrained1 => (forall a. a -> f a) -> Rec r -> Rec (Map f r)
 rmap = rmapc (Proxy @Unconstrained1)
 
+rxform :: ∀ r f g . Forall r Unconstrained1 => (forall a. f a -> g a) -> Rec (Map f r) -> Rec (Map g r)
+rxform = rxformc @r (Proxy @Unconstrained1)
+
 type family Map (f :: a -> b) (r :: Row a) :: Row b where Map f (R r) = R (RM f r)
 
 class RowMap (r :: Row *) where
@@ -409,6 +413,7 @@ instance Forall (R '[]) c where
   eraseToHashMap _ _ _ = M.empty
   eraseZip _ _ _ _ = []
   rmapc _ _ _ = empty
+  rxformc _ _ _ = empty
 
 instance (KnownSymbol l, Forall (R t) c, c a) => Forall (R (l :-> a ': t)) c where
   rinit c f = unsafeInjectFront l f (rinit c f) where l = Label :: Label l
@@ -428,6 +433,10 @@ instance (KnownSymbol l, Forall (R t) c, c a) => Forall (R (l :-> a ': t)) c whe
   rmapc c f r = unsafeInjectFront l (f (r .! l)) (rmapc @_ @_ @f c f (r .- l))
     where l = Label :: Label l
 
+  rxformc :: ∀ f g . Proxy c -> (forall a. c a => f a -> g a) -> Rec (Map f (R (l :-> a ': t))) -> Rec (Map g (R (l :-> a ': t)))
+  rxformc c f r = unsafeInjectFront l (f (r .! l)) (rxformc @(R t) @_ @f @g c f (r .- l))
+    where l = Label :: Label l
+
 show' :: (IsString s, Show a) => a -> s
 show' = fromString . show