diff --git a/docs/users_guide/exts/ffi.rst b/docs/users_guide/exts/ffi.rst index 2889fb141008f28fb95c423b9c5afb3b1857c0b4..e3bf1a75727ea535059d8df6ff39d785594c04fd 100644 --- a/docs/users_guide/exts/ffi.rst +++ b/docs/users_guide/exts/ffi.rst @@ -998,7 +998,7 @@ the data. We can do it like this: sp <- newStablePtrPrimMVar mvar fp <- mallocForeignPtr withForeignPtr fp $ \presult -> do - cap <- threadCapability =<< myThreadId + (cap, _) <- threadCapability =<< myThreadId scheduleCallback sp cap presult takeMVar mvar `onException` forkIO (do takeMVar mvar; touchForeignPtr fp)