Add Table instance for Solo

rel8.cabal

@@ -20,7 +20,7 @@ source-repository head
 library
   build-depends:
       aeson
-    , base ^>= 4.14 || ^>=4.15 || ^>=4.16
+    , base ^>=4.15 || ^>=4.16
     , bifunctors
     , bytestring
     , case-insensitive

src/Rel8/Table.hs

@@ -25,6 +25,7 @@ where
 -- base
 import Data.Functor.Identity ( Identity( Identity ) )
 import Data.Kind ( Constraint, Type )
+import Data.Tuple ( Solo( Solo ) )
 import GHC.Generics ( Generic, Rep, from, to )
 import Prelude hiding ( null )
 
@@ -181,6 +182,18 @@ type instance Eval (TSerialize expr a) =
   )
 
 
+instance Table context a => Table context (Solo a) where
+  type Columns (Solo a) = Columns a
+  type Context (Solo a) = Context a
+  type FromExprs (Solo a) = Solo (FromExprs a)
+  type Transpose to (Solo a) = Solo (Transpose to a)
+
+  toColumns (Solo a) = toColumns a
+  fromColumns = Solo . fromColumns
+  toResult (Solo a) = toResult @_ @a a
+  fromResult = Solo . fromResult @_ @a
+
+
 instance (Table context a, Table context b) => Table context (a, b)
 
 

src/Rel8/Table/Eq.hs

@@ -23,6 +23,7 @@ import Data.Foldable ( foldl' )
 import Data.Functor.Const ( Const( Const ), getConst )
 import Data.Kind ( Constraint, Type )
 import Data.List.NonEmpty ( NonEmpty( (:|) ) )
+import Data.Tuple ( Solo )
 import GHC.Generics ( Rep )
 import Prelude
 
@@ -66,6 +67,10 @@ instance Sql DBEq a => EqTable (Expr a) where
   eqTable = HIdentity Dict
 
 
+instance EqTable a => EqTable (Solo a) where
+  eqTable = eqTable @a
+
+
 instance (EqTable a, EqTable b) => EqTable (a, b)
 
 

src/Rel8/Table/Ord.hs

@@ -20,6 +20,7 @@ where
 -- base
 import Data.Functor.Const ( Const( Const ), getConst )
 import Data.Kind ( Constraint, Type )
+import Data.Tuple ( Solo )
 import GHC.Generics ( Rep )
 import Prelude hiding ( seq )
 
@@ -66,6 +67,10 @@ instance Sql DBOrd a => OrdTable (Expr a) where
   ordTable = HIdentity Dict
 
 
+instance OrdTable a => OrdTable (Solo a) where
+  ordTable = ordTable @a
+
+
 instance (OrdTable a, OrdTable b) => OrdTable (a, b)
 
 

src/Rel8/Table/Serialize.hs

@@ -19,6 +19,7 @@ where
 import Data.Functor.Identity ( Identity( Identity ) )
 import Data.Kind ( Constraint, Type )
 import Data.List.NonEmpty ( NonEmpty )
+import Data.Tuple (Solo)
 import Prelude
 
 -- hasql
@@ -57,6 +58,9 @@ instance (Sql DBType a, NotNull a, x ~ Maybe a) => ToExprs (Expr x) (Maybe a)
 instance (Sql DBType a, NotNull a, x ~ NonEmpty a) => ToExprs (Expr x) (NonEmpty a)
 
 
+instance (ToExprs exprs a, x ~ Solo exprs) => ToExprs x (Solo a)
+
+
 instance (ToExprs exprs1 a, ToExprs exprs2 b, x ~ (exprs1, exprs2)) =>
   ToExprs x (a, b)