relational-query: untype-guard: move case definitions.

relational-query/src/Database/Relational/SqlSyntax/Query.hs

@@ -11,17 +11,14 @@
 module Database.Relational.SqlSyntax.Query (
   flatSubQuery, aggregatedSubQuery,
   union, except, intersect,
-  caseSearch, case',
   ) where
 
 import Database.Relational.Internal.Config (Config)
 import Database.Relational.SqlSyntax.Types
   (Duplication (..), SetOp (..), BinOp (..),
    OrderingTerm, AggregateElem,
-   JoinProduct, WhenClauses (..), CaseClause (..), SubQuery (..),
+   JoinProduct, SubQuery (..),
-   Column (..), Tuple, Guard, )
+   Tuple, Guard, )
-import Database.Relational.SqlSyntax.Record
-  (Predicate, Record, record, untypeRecord, recordWidth, )
 
 
 -- | Unsafely generate flat 'SubQuery' from untyped components.
@@ -60,36 +57,3 @@ except    =  setBin Except
 -- | Intersect binary operator on 'SubQuery'
 intersect :: Duplication -> SubQuery -> SubQuery -> SubQuery
 intersect =  setBin Intersect
-
-
-whenClauses :: String                     -- ^ Error tag
-            -> [(Record c a, Record c b)] -- ^ Each when clauses
-            -> Record c b                 -- ^ Else result record
-            -> WhenClauses                -- ^ Result clause
-whenClauses eTag ws0 e = d ws0
-  where
-    d []       = error $ eTag ++ ": Empty when clauses!"
-    d ws@(_:_) =
-      WhenClauses [ (untypeRecord p, untypeRecord r) | (p, r) <- ws ]
-      $ untypeRecord e
-
--- | Search case operator correnponding SQL search /CASE/.
---   Like, /CASE WHEN p0 THEN a WHEN p1 THEN b ... ELSE c END/
-caseSearch :: [(Predicate c, Record c a)] -- ^ Each when clauses
-           -> Record c a                  -- ^ Else result record
-           -> Record c a                  -- ^ Result record
-caseSearch ws e =
-    record [ Case c i | i <- [0 .. recordWidth e - 1] ]
-  where
-    c = CaseSearch $ whenClauses "caseSearch" ws e
-
--- | Simple case operator correnponding SQL simple /CASE/.
---   Like, /CASE x WHEN v THEN a WHEN w THEN b ... ELSE c END/
-case' :: Record c a                 -- ^ Record value to match
-      -> [(Record c a, Record c b)] -- ^ Each when clauses
-      -> Record c b                 -- ^ Else result record
-      -> Record c b                 -- ^ Result record
-case' v ws e =
-    record [ Case c i | i <- [0 .. recordWidth e - 1] ]
-  where
-    c = CaseSimple (untypeRecord v) $ whenClauses "case'" ws e

relational-query/src/Database/Relational/SqlSyntax/Record.hs

@@ -19,11 +19,16 @@ module Database.Relational.SqlSyntax.Record (
 
   -- * Predicate to restrict Query result
   Predicate,
+
+  -- * case records
+  caseSearch, case',
 ) where
 
 import Database.Relational.Internal.String (StringSQL)
 import Database.Relational.SqlSyntax.Fold (showColumn)
-import Database.Relational.SqlSyntax.Types (SubQuery, Tuple, Column (..))
+import Database.Relational.SqlSyntax.Types
+  (SubQuery, Tuple, Column (..),
+   WhenClauses (..), CaseClause (..),)
 
 
 -- | Phantom typed record. Projected into Haskell record type 't'.
@@ -58,3 +63,37 @@ typeFromScalarSubQuery = record . (:[]) . Scalar
 recordRawColumns :: Record c r  -- ^ Source 'Record'
                  -> [StringSQL] -- ^ Result SQL string list
 recordRawColumns = map showColumn . untypeRecord
+
+-----
+
+whenClauses :: String                     -- ^ Error tag
+            -> [(Record c a, Record c b)] -- ^ Each when clauses
+            -> Record c b                 -- ^ Else result record
+            -> WhenClauses                -- ^ Result clause
+whenClauses eTag ws0 e = d ws0
+  where
+    d []       = error $ eTag ++ ": Empty when clauses!"
+    d ws@(_:_) =
+      WhenClauses [ (untypeRecord p, untypeRecord r) | (p, r) <- ws ]
+      $ untypeRecord e
+
+-- | Search case operator correnponding SQL search /CASE/.
+--   Like, /CASE WHEN p0 THEN a WHEN p1 THEN b ... ELSE c END/
+caseSearch :: [(Predicate c, Record c a)] -- ^ Each when clauses
+           -> Record c a                  -- ^ Else result record
+           -> Record c a                  -- ^ Result record
+caseSearch ws e =
+    record [ Case c i | i <- [0 .. recordWidth e - 1] ]
+  where
+    c = CaseSearch $ whenClauses "caseSearch" ws e
+
+-- | Simple case operator correnponding SQL simple /CASE/.
+--   Like, /CASE x WHEN v THEN a WHEN w THEN b ... ELSE c END/
+case' :: Record c a                 -- ^ Record value to match
+      -> [(Record c a, Record c b)] -- ^ Each when clauses
+      -> Record c b                 -- ^ Else result record
+      -> Record c b                 -- ^ Result record
+case' v ws e =
+    record [ Case c i | i <- [0 .. recordWidth e - 1] ]
+  where
+    c = CaseSimple (untypeRecord v) $ whenClauses "case'" ws e