Introduce InitializerMaybe, initializeMaybe, withNewMaybeHEADmaster

So that it's easier to use it safely: apparently the recently found
segfault was caused by improper order of freeing the resources, while
withNew/withNewMaybe help to ensure the correct order.

1 files changed, 2 insertions, 10 deletions

diff --git a/Redland/Util.hs b/Redland/Util.hs
index c7862be..0c294ab 100644
--- a/Redland/Util.hs
+++ b/Redland/Util.hs
@@ -181,17 +181,9 @@ statementToTriple statement = do
   pure $ Triple s p o
   where
     componentToTriple :: (ForeignPtr RedlandStatement ->
-                          IO (Maybe (ForeignPtr RedlandNode)))
+                          InitializerMaybe RedlandNode)
                       -> IO (Maybe Node)
-    componentToTriple f = do
-      c <- f statement
-      case c of
-        Just c' -> do
-          n <- redlandNodeToNode c'
-          -- segfaulting without finalization here, not sure why.
-          finalizeForeignPtr c'
-          pure $ Just n
-        Nothing -> pure Nothing
+    componentToTriple f = withNewMaybe (f statement) redlandNodeToNode
 
 -- | A conversion function.
 tripleToStatement :: ForeignPtr RedlandWorld