Control.Concurrent.Capataz.Lens

Documentation

(&) :: a -> (a -> b) -> b infixl 1

& is a reverse application operator. This provides notational convenience. Its precedence is one higher than that of the forward application operator $, which allows & to be nested in $.

>>> 5 & (+1) & show
"6"

Since: base-4.8.0.0

(^.) :: s -> Getting a s a -> a infixl 8

(^.) applies a getter to a value; in other words, it gets a value out of a structure using a getter (which can be a lens, traversal, fold, etc.).

Getting 1st field of a tuple:

(^. _1) :: (a, b) -> a
(^. _1) = fst

When (^.) is used with a traversal, it combines all results using the Monoid instance for the resulting type. For instance, for lists it would be simple concatenation:

>>> ("str","ing") ^. each
"string"

The reason for this is that traversals use Applicative, and the Applicative instance for Const uses monoid concatenation to combine “effects” of Const.

A non-operator version of (^.) is called view, and it's a bit more general than (^.) (it works in MonadReader). If you need the general version, you can get it from microlens-mtl; otherwise there's view available in Lens.Micro.Extras.

set :: ASetter s t a b -> b -> s -> t

set is a synonym for (.~).

Setting the 1st component of a pair:

set _1 :: x -> (a, b) -> (x, b)
set _1 = \x t -> (x, snd t)

Using it to rewrite (<$):

set mapped :: Functor f => a -> f b -> f a
set mapped = (<$)

view :: MonadReader s m => Getting a s a -> m a

supervisorOnFailureL :: (HasSupervisorFailureCallback s, Functor f) => ((SomeException -> m ()) -> f (SomeException -> m ())) -> s m -> f (s m)

Specifies callback sub-routine that gets executed when a supervisor fails.

supervisorOnIntensityReachedL :: (HasSupervisorIntensityReachedCallback s, Functor f) => (m () -> f (m ())) -> s m -> f (s m)

Specifies a callback sub-routine that gets executed when there is a breach in a supervisor's error intensity.

supervisorProcessTerminationOrderL :: (HasSupervisorProcessTerminationOrder s, Functor f) => (ProcessTerminationOrder -> f ProcessTerminationOrder) -> s -> f s

Specifies order in which a supervisor is going to terminate its supervised processes.

supervisorProcessSpecListL :: (HasSupervisorProcessSpecList s, Functor f) => ([ProcessSpec m] -> f [ProcessSpec m]) -> s m -> f (s m)

Specifies a static list of processes that start automatically with a supervisor.

supervisorRestartStrategyL :: (HasSupervisorRestartStrategy s, Functor f) => (SupervisorRestartStrategy -> f SupervisorRestartStrategy) -> s -> f s

Specifies the SupervisorRestartStrategy for a root supervisor.

supervisorPeriodSecondsL :: (HasSupervisorPeriodSeconds s, Functor f) => (NominalDiffTime -> f NominalDiffTime) -> s -> f s

Specifies period of time in which a supervisor can receive a number of errors specified in "supervisorIntensityL".

supervisorIntensityL :: (HasSupervisorIntensity s, Functor f) => (Int -> f Int) -> s -> f s

Specifies how many errors is a supervisor able to handle; check: http://erlang.org/doc/design_principles/sup_princ.html#max_intensity.

onSystemEventL :: Functor f => ((CapatazEvent -> m ()) -> f (CapatazEvent -> m ())) -> CapatazOptions m -> f (CapatazOptions m)

workerOnFailureL :: Functor f => ((SomeException -> m ()) -> f (SomeException -> m ())) -> WorkerOptions m -> f (WorkerOptions m)

Specifies callback that gets executed when worker sub-routine has runtime error.

NOTE: the given sub-routine execution may be interrupted depending on the worker WorkerTerminationPolicy.

workerOnCompletionL :: Functor f => (m () -> f (m ())) -> WorkerOptions m -> f (WorkerOptions m)

Specifies callback that gets executed when worker sub-routine completes with no errors.

NOTE: the given sub-routine execution may be interrupted depending on the worker WorkerTerminationPolicy.

workerOnTerminationL :: Functor f => (m () -> f (m ())) -> WorkerOptions m -> f (WorkerOptions m)

Specifies callback that gets executed when worker sub-routine is terminated by its supervisor; this may happen in case of a capataz system shutdown or when there is an AllForOne restart policy in place.

NOTE: the given sub-routine execution may be interrupted depending on the worker WorkerTerminationPolicy.

workerTerminationPolicyL :: Functor f => (WorkerTerminationPolicy -> f WorkerTerminationPolicy) -> WorkerOptions m -> f (WorkerOptions m)

Specifies how to handle a worker termination. See WorkerTerminationPolicy documentation for more details.

workerRestartStrategyL :: Functor f => (WorkerRestartStrategy -> f WorkerRestartStrategy) -> WorkerOptions m -> f (WorkerOptions m)

Specifies how supervisor should deal with an error when worker fails or completes. See WorkerRestartStrategy documentation for more details.