Bug in code generation for transformers

There was a completely unnecessary hack in `Compiler.compileApplyNode` that used name case to distinguish relation from function arguments to transformer. This broke when combined with module name flattening. The fix uses proper HO type information instead.
vmware · Jun 12, 2019 · a01721f · a01721f
1 parent a06b94b
commit a01721f
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diff --git a/src/Language/DifferentialDatalog/Compile.hs b/src/Language/DifferentialDatalog/Compile.hs
@@ -958,11 +958,12 @@ compileApplyNode d Apply{..} = ApplyNode $
     "    })"                                                                                                                                                   $$
     "}; transformer}"
   where
-    inputs = concatMap (\i ->
-                         if isLower $ head i
+    Transformer{..} = getTransformer d applyTransformer
+    inputs = concatMap (\(i, ti) ->
+                         if hotypeIsFunction (hofType ti)
                             then [rname i]
                             else ["collections.get(&(" <> relId i <> ")).unwrap()", extractValue d (relType $ getRelation d i)])
-                       applyInputs
+                       (zip applyInputs transInputs)
              ++
              map (\o -> parens $ "|v|" <> mkValue' d "v" (relType $ getRelation d o)) applyOutputs
     outputs = map rname applyOutputs

diff --git a/src/Language/DifferentialDatalog/Syntax.hs b/src/Language/DifferentialDatalog/Syntax.hs
@@ -794,11 +794,11 @@ instance Show HOType where
 
 hotypeIsRelation :: HOType -> Bool
 hotypeIsRelation HOTypeRelation{} = True
-hotypeIsRelation _                = True
+hotypeIsRelation _                = False
 
 hotypeIsFunction :: HOType -> Bool
 hotypeIsFunction HOTypeFunction{} = True
-hotypeIsFunction _                = True
+hotypeIsFunction _                = False
 
 -- | Type variables used in transformer declaration in the order they appear in the declaration
 hotypeTypeVars :: HOType -> [String]