Eval: add fun addMetaInfo

Author: Anton-Latukha

ChangeLog.md

@@ -9,8 +9,9 @@
     * added type `TransformF`
 
   * `Nix.Eval`:
-    * added fun
+    * added fun:
       * `evalContent`
+      * `addMetaInfo`
 
 
 ### [(diff)](https://github.com/haskell-nix/hnix/compare/0.13.0.1...0.13.1#files_bucket) 0.13.1 (2021-05-22)

src/Nix.hs

@@ -80,7 +80,7 @@ nixEvalExprLoc
 nixEvalExprLoc mpath =
   nixEval
     mpath
-    (Eval.addStackFrames . Eval.addSourcePositions)
+    Eval.addMetaInfo
     Eval.evalContent
 
 -- | Evaluate a nix expression with tracing in the default context. Note that

src/Nix/Eval.hs

@@ -556,11 +556,18 @@ framedEvalExprLoc
   => NExprLoc
   -> m v
 framedEvalExprLoc =
-  adi evalContent $ addStackFrames @v . addSourcePositions
+  adi evalContent addMetaInfo
 
 -- | Takes annotated expression. Strip from annotation. Evaluate.
 evalContent
   :: MonadNixEval v m
   => Compose (Ann ann) NExprF (m v)
   -> m v
 evalContent = eval . annotated . getCompose
+
+-- | Add source postionss & frame context system.
+addMetaInfo
+  :: forall v m e a
+  . (Framed e m, Scoped v m, Has e SrcSpan, Typeable m, Typeable v)
+  => TransformF NExprLoc (m a)
+addMetaInfo = addStackFrames @v . addSourcePositions

src/Nix/Exec.hs

@@ -526,19 +526,15 @@ evalExprLoc expr =
     let
       pTracedAdi =
         bool
-          (adi Eval.evalContent addMetaInfo)
+          (adi Eval.evalContent Eval.addMetaInfo)
           (join . (`runReaderT` (0 :: Int)) .
             adi
               (addTracing Eval.evalContent)
-              (raise addMetaInfo)
+              (raise Eval.addMetaInfo)
           )
           (tracing opts)
     pTracedAdi expr
-
  where
-  addMetaInfo :: (Fix NExprLocF -> m a) -> Fix NExprLocF -> m a
-  addMetaInfo = addStackFrames @(NValue t f m) . addSourcePositions
-
   raise k f x = ReaderT $ \e -> k (\t -> runReaderT (f t) e) x
 
 exec :: (MonadNix e t f m, MonadInstantiate m) => [Text] -> m (NValue t f m)