Safe Haskell	Safe-Inferred
Language	Haskell2010

Bluefin.Reader

Contents

Synopsis

data Reader r (e :: Effects)
runReader :: forall r (es :: Effects) a. r -> (forall (e :: Effects). Reader r e -> Eff (e :& es) a) -> Eff es a
ask :: forall (e :: Effects) (es :: Effects) r. e :> es => Reader r e -> Eff es r
asks :: forall (e :: Effects) (es :: Effects) r a. e :> es => Reader r e -> (r -> a) -> Eff es a
local :: forall (e1 :: Effects) (es :: Effects) r a. e1 :> es => Reader r e1 -> (r -> r) -> Eff es a -> Eff es a

Documentation

Reader is Bluefin's version of the Control.Monad.Trans.Reader monad.

Handle

data Reader r (e :: Effects) #

Instances details

Handle (Reader r)
Instance details Defined in Bluefin.Internal Methods mapHandle :: forall (e :: Effects) (es :: Effects). e :> es => Reader r e -> Reader r es #

Arguments

:: forall r (es :: Effects) a. r	Initial value for `Reader`.
-> (forall (e :: Effects). Reader r e -> Eff (e :& es) a)
-> Eff es a

Arguments

:: forall (e :: Effects) (es :: Effects) r. e :> es
=> Reader r e	͘
-> Eff es r

Read the value. Note that ask has the property that these two operations are always equivalent:

do
  r1 <- ask re
  r2 <- ask re
  pure (r1, r2)

do
  r <- ask re
  pure (r, r)

Arguments

:: forall (e :: Effects) (es :: Effects) r a. e :> es
=> Reader r e
-> (r -> a)	Read the value modified by this function
-> Eff es a

Read the value modified by a function

Arguments

:: forall (e1 :: Effects) (es :: Effects) r a. e1 :> es
=> Reader r e1
-> (r -> r)	In the body, the reader value is modified by this function.
-> Eff es a	Body
-> Eff es a