Safe Haskell	None
Language	Haskell2010

Bluefin.Jump

Contents

Handle
Handlers
Effectful operations

Description

This is an old interface and will be deprecated in the future. You are encouraged to use Bluefin.Capability.Jump instead.

Synopsis

type Jump = EarlyReturn ()
withJump :: forall (es :: Effects). (forall (e :: Effects). Jump e -> Eff (e :& es) ()) -> Eff es ()
jumpTo :: forall (e :: Effects) (es :: Effects) a. e <: es => Jump e -> Eff es a

Documentation

Jump allows you to jump back to a previously-set location. A "jump" is equivalent to an untyped early return, or more precisely an early return of type (), which is itself an exception of type ().

Handle

type Jump = EarlyReturn () #

Handlers

withJump #

Arguments

:: forall (es :: Effects). (forall (e :: Effects). Jump e -> Eff (e :& es) ())
-> Eff es ()	͘

runPureEff $ withStateSource $ \source -> do
  n <- newState source 5
  total <- newState source 0

  withJump $ \done -> forever $ do
    n' <- get n
    modify total (+ n')
    when (n' == 0) $ jumpTo done
    modify n (subtract 1)

  get total
15

Effectful operations

jumpTo #

Arguments

:: forall (e :: Effects) (es :: Effects) a. e <: es
=> Jump e
-> Eff es a	͘

runPureEff $ withStateSource $ \source -> do
  n <- newState source 5
  total <- newState source 0

  withJump $ \done -> forever $ do
    n' <- get n
    modify total (+ n')
    when (n' == 0) $ jumpTo done
    modify n (subtract 1)

  get total
15