Run the Reader effect with the given initial environment (via Effectful.Reader.Static).

Fetch the value of the environment.

Retrieve a function of the current environment.

asks f ≡ f <$> ask

Execute a computation in a modified environment.

runReader r (local f m) ≡ runReader (f r) m

Assign a label to an effect.

Note: labeled effects are best used together with the effectful-plugin package, as it significantly improves their usability.

The constructor is for sending labeled operations of a dynamically dispatched effect to the handler:

>>> import Effectful.Dispatch.Dynamic

>>> :{
  data X :: Effect where
    X :: X m Int
  type instance DispatchOf X = Dynamic
:}

>>> :{
  runPureEff . runLabeled @"x" (interpret_ $ \X -> pure 333) $ do
    send $ Labeled @"x" X
:}
333