Generalize termConstructor to return its argument in a Monad.

src/Parser.hs

@@ -23,8 +23,8 @@ isOperator = flip Set.member (Set.fromList [ Operator, BinaryOperator ])
 
 -- | Given a function that maps production names to sets of categories, produce
 -- | a Constructor.
-termConstructor :: forall fields. (Show (Record fields), HasField fields Category, HasField fields Range) => Source Char -> SourceSpan -> Record fields -> [Term Text (Record fields)] -> Term Text (Record fields)
-termConstructor source sourceSpan info = cofree . construct
+termConstructor :: forall fields m. (Show (Record fields), HasField fields Category, HasField fields Range, Monad m) => Source Char -> SourceSpan -> Record fields -> [Term Text (Record fields)] -> m (Term Text (Record fields))
+termConstructor source sourceSpan info terms = pure $! cofree (construct terms)
   where
     withDefaultInfo syntax = (info :< syntax)
     errorWith = (seq sourceSpan) . withDefaultInfo . S.Error sourceSpan

src/TreeSitter.hs

@@ -118,6 +118,6 @@ documentToTerm language document blob = alloca $ \ root -> do
           -- Note: The strict application here is semantically important. Without it, we may not evaluate the range until after we’ve exited the scope that `node` was allocated within, meaning `alloca` will free it & other stack data may overwrite it.
           -- We don’t evaluate `sourceSpan` eagerly so that terms which don’t use it don’t pay the toll for it. This places the onus for evaluating it on the termConstructor function.
           let info = range `seq` range .: categoriesForLanguage language (toS name) .: RNil
-          pure $! termConstructor (source blob) sourceSpan info children
+          termConstructor (source blob) sourceSpan info children
         getChild node n out = ts_node_p_named_child node n out >> toTerm out
         {-# INLINE getChild #-}