Control.Monad.Factory.Class

Documentation

class (Monad m, Monad n) => MonadFactory env n m | m -> env n where

Monads which allow to produce component under env, and env can be changed by this procedure.

Methods

getEnv :: m env

Return the environment of the monad.

putEnv :: env -> m ()

Replace the environment inside the monad.

produce

Arguments

:: n component

Open resource

-> (component -> n ())

Close resource

-> m component

Produce a resource component, with open and close.

Instances

MonadMask m => MonadFactory env m (Factory m env)

Defined in Control.Monad.Factory

Methods

getEnv :: Factory m env env

putEnv :: env -> Factory m env ()

produce :: m component -> (component -> m ()) -> Factory m env component

defer :: MonadFactory env n m => n () -> m ()

Defer to run side effect when closeing resource.

asksEnv :: MonadFactory env n m => (env -> a) -> m a

Asks sub value of env.

withEnv :: MonadFactory env n m => (env -> m env) -> m ()

Change environment env.

modifyEnv :: MonadFactory env n m => (env -> env) -> m ()

Modify environment env.

runEnv :: MonadFactory env n m => m c -> m (env, c)

Run factory, return component c and updated environment env.