Safe Haskell	None
Language	GHC2021

Effectful.Environment.Guard.Static

Contents

Effect
- Handler
High level combinators
Low level functions

Synopsis

data EnvGuard (a :: Type -> Type) b
runEnvGuard :: forall (es :: [Effect]) a. IOE :> es => Eff (EnvGuard ': es) a -> Eff es a
data ExpectEnv
- = ExpectEnvSet
- | ExpectEnvEquals String
- | ExpectEnvPredicate (String -> Bool)
withGuard :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> ExpectEnv -> Eff es a -> Eff es (Maybe a)
withGuard_ :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> ExpectEnv -> Eff es a -> Eff es ()
guardOrElse :: forall (es :: [Effect]) a e. (EnvGuard :> es, HasCallStack) => String -> ExpectEnv -> Eff es a -> Eff es e -> Eff es (Either e a)
guardOrElse' :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> ExpectEnv -> Eff es a -> Eff es a -> Eff es a
guardSet :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> Eff es a -> Eff es (Maybe a)
guardSet_ :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> Eff es a -> Eff es ()
guardEquals :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> String -> Eff es a -> Eff es (Maybe a)
guardEquals_ :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> String -> Eff es a -> Eff es ()
guardPredicate :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> (String -> Bool) -> Eff es a -> Eff es (Maybe a)
guardPredicate_ :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> (String -> Bool) -> Eff es a -> Eff es ()

Effect

data EnvGuard (a :: Type -> Type) b Source #

Static effect for EnvGuard.

Since: 0.1

Instances

Instances details

type DispatchOf EnvGuard Source #
Instance details Defined in Effectful.Environment.Guard.Static type DispatchOf EnvGuard = 'Static 'WithSideEffects
data StaticRep EnvGuard Source #
Instance details Defined in Effectful.Environment.Guard.Static data StaticRep EnvGuard = MkEnvGuard

Handler

runEnvGuard :: forall (es :: [Effect]) a. IOE :> es => Eff (EnvGuard ': es) a -> Eff es a Source #

Runs an EnvGuard effect.

Since: 0.1

High level combinators

data ExpectEnv Source #

The expectation for an environment variable lookup.

Since: env-guard-0.1.1

Constructors

ExpectEnvSet

Expect that the environment variable is set (i.e. contents can be anything).

Since: env-guard-0.1.1

ExpectEnvEquals String

Expect that the environment variable is set and the contents equals the string. This is case-insensitive.

Since: env-guard-0.1.1

ExpectEnvPredicate (String -> Bool)

Expect that the environment variable is set and its contents satisfies the predicate.

Since: env-guard-0.1.1

Instances

Instances details

Show ExpectEnv	Since: env-guard-0.1.1
Instance details Defined in System.Environment.Guard.Lifted Methods showsPrec :: Int -> ExpectEnv -> ShowS # show :: ExpectEnv -> String # showList :: [ExpectEnv] -> ShowS #

withGuard :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> ExpectEnv -> Eff es a -> Eff es (Maybe a) Source #

Since: 0.1

withGuard_ :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> ExpectEnv -> Eff es a -> Eff es () Source #

Since: 0.1

guardOrElse Source #

Arguments

:: forall (es :: [Effect]) a e. (EnvGuard :> es, HasCallStack)
=> String	The environment variable.
-> ExpectEnv	The expectation.
-> Eff es a	The action to run if the expectation succeeds.
-> Eff es e	The action to run if the expectation fails.
-> Eff es (Either e a)	The result.

Since: 0.1

guardOrElse' Source #

Arguments

:: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack)
=> String	The environment variable.
-> ExpectEnv	The expectation.
-> Eff es a	The action to run if the expectation succeeds.
-> Eff es a	The action to run if the expectation fails.
-> Eff es a	The result.

Since: 0.1

Low level functions

Checking environment variable is set

guardSet :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> Eff es a -> Eff es (Maybe a) Source #

Since: 0.1

guardSet_ :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> Eff es a -> Eff es () Source #

Since: 0.1

Checking environment variable match

guardEquals :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> String -> Eff es a -> Eff es (Maybe a) Source #

Since: 0.1

guardEquals_ :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> String -> Eff es a -> Eff es () Source #

Since: 0.1

Checking environment variable predicate

guardPredicate :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> (String -> Bool) -> Eff es a -> Eff es (Maybe a) Source #

Since: 0.1

guardPredicate_ :: forall (es :: [Effect]) a. (EnvGuard :> es, HasCallStack) => String -> (String -> Bool) -> Eff es a -> Eff es () Source #

Since: 0.1