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{-# LANGUAGE Rank2Types #-}
{-# LANGUAGE LiberalTypeSynonyms #-}
-----------------------------------------------------------------------------
-- |
-- Module : Control.Lens.Setter
-- Copyright : (C) 2012 Edward Kmett
-- License : BSD-style (see the file LICENSE)
-- Maintainer : Edward Kmett <ekmett@gmail.com>
-- Stability : provisional
-- Portability : Rank2Types
--
-- A @'Setter' a b c d@ is a generalization of 'fmap' from 'Functor'. It allows you to map into a
-- structure and change out the contents, but it isn't strong enough to allow you to
-- enumerate those contents. Starting with @fmap :: 'Functor' f => (c -> d) -> f c -> f d@
-- we monomorphize the type to obtain @(c -> d) -> a -> b@ and then decorate it with 'Identity' to obtain
--
-- @type 'Setter' a b c d = (c -> 'Identity' d) -> a -> 'Identity' b@
--
-- Every 'Control.Lens.Traversal.Traversal' is a valid 'Setter', since 'Identity' is 'Applicative'.
--
-- Everything you can do with a 'Functor', you can do with a 'Setter'. There
-- are combinators that generalize 'fmap' and ('<$').
----------------------------------------------------------------------------
module Control.Lens.Setter
(
-- * Setters
Setter
-- * Building Setters
, sets
-- * Common Setters
, mapped
-- * Functional Combinators
, over
, mapOf
, set
, (.~), (%~)
, (+~), (-~), (*~), (//~), (^~), (^^~), (**~), (||~), (&&~), (<.~)
-- * State Combinators
, (.=), (%=)
, (+=), (-=), (*=), (//=), (^=), (^^=), (**=), (||=), (&&=), (<.=)
, (<~)
-- * Setter Internals
, Setting
, SimpleSetting
-- * Simplicity
, SimpleSetter
) where
import Control.Applicative
import Control.Lens.Internal
import Control.Monad.State.Class as State
infixr 4 .~, +~, *~, -~, //~, ^~, ^^~, **~, &&~, ||~, %~, <.~
infix 4 .=, +=, *=, -=, //=, ^=, ^^=, **=, &&=, ||=, %=, <.=
infixr 2 <~
------------------------------------------------------------------------------
-- Setters
------------------------------------------------------------------------------
-- |
-- The only 'Control.Lens.Type.Lens'-like law that can apply to a 'Setter' @l@ is that
--
-- @'set' l c ('set' l b a) = 'set' l c a@
--
-- You can't 'view' a 'Setter' in general, so the other two laws are irrelevant.
--
-- However, two 'Functor' laws apply to a 'Setter':
--
-- @
-- 'over' l 'id' = 'id'
-- 'over' l f . 'over' l g = 'over' l (f . g)
-- @
--
-- These an be stated more directly:
--
-- @
-- l 'pure' = 'pure'
-- l f . 'untainted' . l g = l (f . 'untainted' . g)
-- @
--
-- You can compose a 'Setter' with a 'Control.Lens.Type.Lens' or a 'Control.Lens.Traversal.Traversal' using ('.') from the Prelude
-- and the result is always only a 'Setter' and nothing more.
type Setter a b c d = forall f. Settable f => (c -> f d) -> a -> f b
-- |
-- Running a 'Setter' instantiates it to a concrete type.
--
-- When consuming a setter directly to perform a mapping, you can use this type, but most
-- user code will not need to use this type.
--
-- By choosing 'Mutator' rather than 'Identity', we get nicer error messages.
type Setting a b c d = (c -> Mutator d) -> a -> Mutator b
-- |
--
-- A Simple Setter is just a 'Setter' that doesn't change the types.
--
-- These are particularly common when talking about monomorphic containers. e.g.
--
-- @'sets' Data.Text.map :: 'SimpleSetter' 'Data.Text.Internal.Text' 'Char'@
--
-- @type 'SimpleSetter' = 'Control.Lens.Type.Simple' 'Setter'@
type SimpleSetter a b = Setter a a b b
-- |
-- This is a useful alias for use when consuming a 'SimpleSetter'.
--
-- Most user code will never have to use this type.
--
-- @type 'SimpleSetting' m = 'Control.Lens.Type.Simple' 'Setting'@
type SimpleSetting a b = Setting a a b b
-----------------------------------------------------------------------------
-- Setters
-----------------------------------------------------------------------------
-- | This setter can be used to map over all of the values in a 'Functor'.
--
-- @
-- 'fmap' = 'over' 'mapped'
-- 'Data.Traversable.fmapDefault' = 'over' 'Data.Traversable.traverse'
-- ('<$') = 'set' 'mapped'
-- @
mapped :: Functor f => Setter (f a) (f b) a b
mapped = sets fmap
{-# INLINE mapped #-}
-- | Build a Setter from a map-like function.
--
-- Your supplied function @f@ is required to satisfy:
--
-- @
-- f 'id' = 'id'
-- f g '.' f h = f (g '.' h)
-- @
--
-- Equational reasoning:
--
-- @
-- 'sets' . 'over' = 'id'
-- 'over' . 'sets' = 'id'
-- @
--
-- Another way to view 'sets' is that it takes a \"semantic editor combinator\"
-- and transforms it into a 'Setter'.
sets :: ((c -> d) -> a -> b) -> Setter a b c d
sets f g = pure . f (untainted . g)
{-# INLINE sets #-}
-----------------------------------------------------------------------------
-- Using Setters
-----------------------------------------------------------------------------
-- | Modify the target of a 'Control.Lens.Type.Lens' or all the targets of a 'Setter' or 'Control.Lens.Traversal.Traversal'
-- with a function.
--
-- @
-- 'fmap' = 'over' 'mapped'
-- 'Data.Traversable.fmapDefault' = 'over' 'Data.Traversable.traverse'
-- 'sets' . 'over' = 'id'
-- 'over' . 'sets' = 'id'
-- @
--
-- Another way to view 'over' is to say that it transformers a 'Setter' into a
-- \"semantic editor combinator\".
--
-- @'over' :: 'Setter' a b c d -> (c -> d) -> a -> b@
over :: Setting a b c d -> (c -> d) -> a -> b
over l f = runMutator . l (Mutator . f)
{-# INLINE over #-}
-- | Modify the target of a 'Control.Lens.Type.Lens' or all the targets of a 'Setter' or 'Control.Lens.Traversal.Traversal'
-- with a function. This is an alias for 'over' that is provided for consistency.
--
-- @
-- 'mapOf' = 'over'
-- 'fmap' = 'mapOf' 'mapped'
-- 'fmapDefault' = 'mapOf' 'traverse'
-- 'sets' . 'mapOf' = 'id'
-- 'mapOf' . 'sets' = 'id'
-- @
--
-- @
-- mapOf :: 'Setter' a b c d -> (c -> d) -> a -> b
-- mapOf :: 'Control.Lens.Iso.Iso' a b c d -> (c -> d) -> a -> b
-- mapOf :: 'Control.Lens.Type.Lens' a b c d -> (c -> d) -> a -> b
-- mapOf :: 'Control.Lens.Traversal.Traversal' a b c d -> (c -> d) -> a -> b
-- @
mapOf :: Setting a b c d -> (c -> d) -> a -> b
mapOf = over
{-# INLINE mapOf #-}
-- | Replace the target of a 'Control.Lens.Type.Lens' or all of the targets of a 'Setter'
-- or 'Control.Lens.Traversal.Traversal' with a constant value.
--
-- @('<$') = 'set' 'mapped'@
--
-- >>> import Control.Lens
-- >>> set _2 "hello" (1,())
-- (1,"hello")
--
-- >>> set mapped () [1,2,3,4]
-- [(),(),(),()]
--
-- Note: Attempting to 'set' a 'Fold' or 'Getter' will fail at compile time with an
-- relatively nice error message.
--
-- @
-- set :: 'Setter' a b c d -> d -> a -> b
-- set :: 'Control.Lens.Iso.Iso' a b c d -> d -> a -> b
-- set :: 'Control.Lens.Type.Lens' a b c d -> d -> a -> b
-- set :: 'Control.Lens.Traversal.Traversal' a b c d -> d -> a -> b
-- @
set :: Setting a b c d -> d -> a -> b
set l d = runMutator . l (\_ -> Mutator d)
{-# INLINE set #-}
-- | Modifies the target of a 'Control.Lens.Type.Lens' or all of the targets of a 'Setter' or
-- 'Control.Lens.Traversal.Traversal' with a user supplied function.
--
-- This is an infix version of 'over'
--
-- @
-- 'fmap' f = 'mapped' '%~' f
-- 'Data.Traversable.fmapDefault' f = 'traverse' '%~' f
-- @
--
-- >>> import Control.Lens
-- >>> _2 %~ length $ (1,"hello")
-- (1,5)
--
-- @
-- (%~) :: 'Setter' a b c d -> (c -> d) -> a -> b
-- (%~) :: 'Control.Lens.Iso.Iso' a b c d -> (c -> d) -> a -> b
-- (%~) :: 'Control.Lens.Type.Lens' a b c d -> (c -> d) -> a -> b
-- (%~) :: 'Control.Lens.Traversal.Traversal' a b c d -> (c -> d) -> a -> b
-- @
(%~) :: Setting a b c d -> (c -> d) -> a -> b
(%~) = over
{-# INLINE (%~) #-}
-- | Replace the target of a 'Control.Lens.Type.Lens' or all of the targets of a 'Setter'
-- or 'Control.Lens.Traversal.Traversal' with a constant value.
--
-- This is an infix version of 'set', provided for consistency with ('.=')
--
-- @f '<$' a = 'mapped' '.~' f '$' a@
--
-- >>> import Control.Lens
-- >>> _1 .~ "hello" $ (42,"world")
-- ("hello","world")
--
-- @
-- (.~) :: 'Setter' a b c d -> d -> a -> b
-- (.~) :: 'Control.Lens.Iso.Iso' a b c d -> d -> a -> b
-- (.~) :: 'Control.Lens.Type.Lens' a b c d -> d -> a -> b
-- (.~) :: 'Control.Lens.Traversal.Traversal' a b c d -> d -> a -> b
-- @
(.~) :: Setting a b c d -> d -> a -> b
(.~) = set
{-# INLINE (.~) #-}
-- | Set with pass-through
--
-- This is mostly present for consistency, but may be useful for for chaining assignments
--
-- If you do not need a copy of the intermediate result, then using @l '.~' d@ directly is a good idea.
--
-- @
-- (\<.~) :: 'Setter' a b c d -> d -> a -> (d, b)
-- (\<.~) :: 'Control.Lens.Iso.Iso' a b c d -> d -> a -> (d, b)
-- (\<.~) :: 'Control.Lens.Type.Lens' a b c d -> d -> a -> (d, b)
-- (\<.~) :: 'Control.Lens.Traversal.Traversal' a b c d -> d -> a -> (d, b)
-- @
(<.~) :: Setting a b c d -> d -> a -> (d, b)
l <.~ d = \a -> (d, l .~ d $ a)
{-# INLINE (<.~) #-}
-- | Increment the target(s) of a numerically valued 'Control.Lens.Type.Lens', 'Setter' or 'Control.Lens.Traversal.Traversal'
--
-- >>> import Control.Lens
-- >>> _1 +~ 1 $ (1,2)
-- (2,2)
--
-- @
-- (+~) :: Num c => 'Setter' a b c c -> c -> a -> b
-- (+~) :: Num c => 'Control.Lens.Iso.Iso' a b c c -> c -> a -> b
-- (+~) :: Num c => 'Control.Lens.Type.Lens' a b c c -> c -> a -> b
-- (+~) :: Num c => 'Control.Lens.Traversal.Traversal' a b c c -> c -> a -> b
-- @
(+~) :: Num c => Setting a b c c -> c -> a -> b
l +~ n = over l (+ n)
{-# INLINE (+~) #-}
-- | Multiply the target(s) of a numerically valued 'Control.Lens.Type.Lens', 'Control.Lens.Iso.Iso', 'Setter' or 'Control.Lens.Traversal.Traversal'
--
-- >>> import Control.Lens
-- >>> _2 *~ 4 $ (1,2)
-- (1,8)
--
-- @
-- (*~) :: 'Num' c => 'Setter' a b c c -> c -> a -> b
-- (*~) :: 'Num' c => 'Control.Lens.Iso.Iso' a b c c -> c -> a -> b
-- (*~) :: 'Num' c => 'Control.Lens.Type.Lens' a b c c -> c -> a -> b
-- (*~) :: 'Num' c => 'Control.Lens.Traversal.Traversal' a b c c -> c -> a -> b
-- @
(*~) :: Num c => Setting a b c c -> c -> a -> b
l *~ n = over l (* n)
{-# INLINE (*~) #-}
-- | Decrement the target(s) of a numerically valued 'Control.Lens.Type.Lens', 'Control.Lens.Iso.Iso', 'Setter' or 'Control.Lens.Traversal.Traversal'
--
-- >>> import Control.Lens
-- >>> _1 -~ 2 $ (1,2)
-- (-1,2)
--
-- @
-- (-~) :: 'Num' c => 'Setter' a b c c -> c -> a -> b
-- (-~) :: 'Num' c => 'Control.Lens.Iso.Iso' a b c c -> c -> a -> b
-- (-~) :: 'Num' c => 'Control.Lens.Type.Lens' a b c c -> c -> a -> b
-- (-~) :: 'Num' c => 'Control.Lens.Traversal.Traversal' a b c c -> c -> a -> b
-- @
(-~) :: Num c => Setting a b c c -> c -> a -> b
l -~ n = over l (subtract n)
{-# INLINE (-~) #-}
-- | Divide the target(s) of a numerically valued 'Control.Lens.Type.Lens', 'Control.Lens.Iso.Iso', 'Setter' or 'Control.Lens.Traversal.Traversal'
--
-- @
-- (//~) :: 'Fractional' c => 'Setter' a b c c -> c -> a -> b
-- (//~) :: 'Fractional' c => 'Control.Lens.Iso.Iso' a b c c -> c -> a -> b
-- (//~) :: 'Fractional' c => 'Control.Lens.Type.Lens' a b c c -> c -> a -> b
-- (//~) :: 'Fractional' c => 'Control.Lens.Traversal.Traversal' a b c c -> c -> a -> b
-- @
(//~) :: Fractional c => Setting a b c c -> c -> a -> b
l //~ n = over l (/ n)
-- | Raise the target(s) of a numerically valued 'Control.Lens.Type.Lens', 'Setter' or 'Control.Lens.Traversal.Traversal' to a non-negative integral power
--
-- >>> import Control.Lens
-- >>> _2 ^~ 2 $ (1,3)
-- (1,9)
(^~) :: (Num c, Integral e) => Setting a b c c -> e -> a -> b
l ^~ n = over l (^ n)
{-# INLINE (^~) #-}
-- | Raise the target(s) of a fractionally valued 'Control.Lens.Type.Lens', 'Setter' or 'Control.Lens.Traversal.Traversal' to an integral power
--
-- >>> import Control.Lens
-- >>> _2 ^^~ (-1) $ (1,2)
-- (1,0.5)
--
-- @
-- (^^~) :: ('Fractional' c, 'Integral' e) => 'Setter' a b c c -> e -> a -> b
-- (^^~) :: ('Fractional' c, 'Integral' e) => 'Control.Lens.Iso.Iso' a b c c -> e -> a -> b
-- (^^~) :: ('Fractional' c, 'Integral' e) => 'Control.Lens.Type.Lens' a b c c -> e -> a -> b
-- (^^~) :: ('Fractional' c, 'Integral' e) => 'Control.Lens.Traversal.Traversal' a b c c -> e -> a -> b
-- @
--
(^^~) :: (Fractional c, Integral e) => Setting a b c c -> e -> a -> b
l ^^~ n = over l (^^ n)
{-# INLINE (^^~) #-}
-- | Raise the target(s) of a floating-point valued 'Control.Lens.Type.Lens', 'Setter' or 'Control.Lens.Traversal.Traversal' to an arbitrary power.
--
-- >>> import Control.Lens
-- >>> _2 **~ pi $ (1,3)
-- (1,31.54428070019754)
--
-- @
-- (**~) :: 'Floating' c => 'Setter' a b c c -> c -> a -> b
-- (**~) :: 'Floating' c => 'Control.Lens.Iso.Iso' a b c c -> c -> a -> b
-- (**~) :: 'Floating' c => 'Control.Lens.Type.Lens' a b c c -> c -> a -> b
-- (**~) :: 'Floating' c => 'Control.Lens.Traversal.Traversal' a b c c -> c -> a -> b
-- @
(**~) :: Floating c => Setting a b c c -> c -> a -> b
l **~ n = over l (** n)
{-# INLINE (**~) #-}
-- | Logically '||' the target(s) of a 'Bool'-valued 'Control.Lens.Type.Lens' or 'Setter'
--
-- >>> :m + Control.Lens Data.Pair.Lens
--
-- >>> both ||~ True $ (False,True)
-- (True,True)
--
-- >>> both ||~ False $ (False,True)
-- (False,True)
--
-- @
-- (||~):: 'Setter' a b 'Bool' 'Bool' -> 'Bool' -> a -> b
-- (||~):: 'Control.Lens.Iso.Iso' a b 'Bool' 'Bool' -> 'Bool' -> a -> b
-- (||~):: 'Control.Lens.Type.Lens' a b 'Bool' 'Bool' -> 'Bool' -> a -> b
-- (||~):: 'Control.Lens.Traversal.Traversal' a b 'Bool' 'Bool' -> 'Bool' -> a -> b
-- @
(||~):: Setting a b Bool Bool -> Bool -> a -> b
l ||~ n = over l (|| n)
{-# INLINE (||~) #-}
-- | Logically '&&' the target(s) of a 'Bool'-valued 'Control.Lens.Type.Lens' or 'Setter'
--
-- >>> :m + Control.Lens Data.Pair.Lens
--
-- >>> both &&~ True $ (False, True)
-- (False,True)
--
-- >>> both &&~ False $ (False, True)
-- (False,False)
--
-- @
-- (&&~):: 'Setter' a b 'Bool' 'Bool' -> 'Bool' -> a -> b
-- (&&~):: 'Control.Lens.Iso.Iso' a b 'Bool' 'Bool' -> 'Bool' -> a -> b
-- (&&~):: 'Control.Lens.Type.Lens' a b 'Bool' 'Bool' -> 'Bool' -> a -> b
-- (&&~):: 'Control.Lens.Traversal.Traversal' a b 'Bool' 'Bool' -> 'Bool' -> a -> b
-- @
(&&~) :: Setting a b Bool Bool -> Bool -> a -> b
l &&~ n = over l (&& n)
{-# INLINE (&&~) #-}
------------------------------------------------------------------------------
-- Using Setters with State
------------------------------------------------------------------------------
-- | Replace the target of a 'Control.Lens.Type.Lens' or all of the targets of a 'Setter' or 'Control.Lens.Traversal.Traversal' in our monadic
-- state with a new value, irrespective of the old.
--
-- @
-- (.=) :: 'MonadState' a m => 'Control.Lens.Iso.Iso' a a c d -> d -> m ()
-- (.=) :: 'MonadState' a m => 'Control.Lens.Type.Lens' a a c d -> d -> m ()
-- (.=) :: 'MonadState' a m => 'Control.Lens.Traversal.Traversal' a a c d -> d -> m ()
-- (.=) :: 'MonadState' a m => 'Setter' a a c d -> d -> m ()
-- @
--
-- "It puts the state in the monad or it gets the hose again."
(.=) :: MonadState a m => Setting a a c d -> d -> m ()
l .= b = State.modify (l .~ b)
{-# INLINE (.=) #-}
-- | Map over the target of a 'Control.Lens.Type.Lens' or all of the targets of a 'Setter' or 'Control.Lens.Traversal.Traversal' in our monadic state.
--
-- @
-- (%=) :: 'MonadState' a m => 'Control.Lens.Iso.Iso' a a c d -> (c -> d) -> m ()
-- (%=) :: 'MonadState' a m => 'Control.Lens.Type.Lens' a a c d -> (c -> d) -> m ()
-- (%=) :: 'MonadState' a m => 'Control.Lens.Traversal.Traversal' a a c d -> (c -> d) -> m ()
-- (%=) :: 'MonadState' a m => 'Setter' a a c d -> (c -> d) -> m ()
-- @
(%=) :: MonadState a m => Setting a a c d -> (c -> d) -> m ()
l %= f = State.modify (l %~ f)
{-# INLINE (%=) #-}
-- | Modify the target(s) of a 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens', 'Control.Lens.Iso.Iso', 'Setter' or 'Control.Lens.Traversal.Traversal' by adding a value
--
-- Example:
--
-- @
-- fresh :: MonadState Int m => m Int
-- fresh = do
-- 'id' '+=' 1
-- 'use' 'id'
-- @
--
-- @
-- (+=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Setter' a b -> b -> m ()
-- (+=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Iso.Iso' a b -> b -> m ()
-- (+=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens' a b -> b -> m ()
-- (+=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Traversal.Traversal' a b -> b -> m ()
-- @
(+=) :: (MonadState a m, Num b) => SimpleSetting a b -> b -> m ()
l += b = State.modify (l +~ b)
{-# INLINE (+=) #-}
-- | Modify the target(s) of a 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens', 'Control.Lens.Iso.Iso', 'Setter' or 'Control.Lens.Traversal.Traversal' by subtracting a value
--
-- @
-- (-=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Setter' a b -> b -> m ()
-- (-=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Iso.Iso' a b -> b -> m ()
-- (-=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens' a b -> b -> m ()
-- (-=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Traversal.Traversal' a b -> b -> m ()
-- @
(-=) :: (MonadState a m, Num b) => SimpleSetting a b -> b -> m ()
l -= b = State.modify (l -~ b)
{-# INLINE (-=) #-}
-- | Modify the target(s) of a 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens', 'Control.Lens.Iso.Iso', 'Setter' or 'Control.Lens.Traversal.Traversal' by multiplying by value.
--
-- @ballSpeed '.' 'Data.Pair.Lens.both' '*=' speedMultiplier@
--
-- @
-- (*=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Setter' a b -> b -> m ()
-- (*=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Iso.Iso' a b -> b -> m ()
-- (*=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens' a b -> b -> m ()
-- (*=) :: ('MonadState' a m, 'Num' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Traversal.Traversal' a b -> b -> m ()
-- @
(*=) :: (MonadState a m, Num b) => SimpleSetting a b -> b -> m ()
l *= b = State.modify (l *~ b)
{-# INLINE (*=) #-}
-- | Modify the target(s) of a 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens', 'Control.Lens.Iso.Iso', 'Setter' or 'Control.Lens.Traversal.Traversal' by dividing by a value.
--
-- @
-- (//=) :: ('MonadState' a m, 'Fractional' b) => 'Control.Lens.Type.Simple' 'Setter' a b -> b -> m ()
-- (//=) :: ('MonadState' a m, 'Fractional' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Iso.Iso' a b -> b -> m ()
-- (//=) :: ('MonadState' a m, 'Fractional' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens' a b -> b -> m ()
-- (//=) :: ('MonadState' a m, 'Fractional' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Traversal.Traversal' a b -> b -> m ()
-- @
(//=) :: (MonadState a m, Fractional b) => SimpleSetting a b -> b -> m ()
l //= b = State.modify (l //~ b)
{-# INLINE (//=) #-}
-- | Raise the target(s) of a numerically valued 'Control.Lens.Type.Lens', 'Setter' or 'Control.Lens.Traversal.Traversal' to a non-negative integral power.
--
-- @
-- (^=) :: ('MonadState' a m, 'Fractional' b, 'Integral' c) => 'Control.Lens.Type.Simple' 'Setter' a b -> c -> m ()
-- (^=) :: ('MonadState' a m, 'Fractional' b, 'Integral' c) => 'Control.Lens.Type.Simple' 'Control.Lens.Iso.Iso' a b -> c -> m ()
-- (^=) :: ('MonadState' a m, 'Fractional' b, 'Integral' c) => 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens' a b -> c -> m ()
-- (^=) :: ('MonadState' a m, 'Fractional' b, 'Integral' c) => 'Control.Lens.Type.Simple' 'Control.Lens.Traversal.Traversal' a b -> c -> m ()
-- @
(^=) :: (MonadState a m, Fractional b, Integral c) => SimpleSetting a b -> c -> m ()
l ^= c = State.modify (l ^~ c)
{-# INLINE (^=) #-}
-- | Raise the target(s) of a numerically valued 'Control.Lens.Type.Lens', 'Setter' or 'Control.Lens.Traversal.Traversal' to an integral power.
--
-- @
-- (^^=) :: ('MonadState' a m, 'Fractional' b, 'Integral' c) => 'Control.Lens.Type.Simple' 'Setter' a b -> c -> m ()
-- (^^=) :: ('MonadState' a m, 'Fractional' b, 'Integral' c) => 'Control.Lens.Type.Simple' 'Control.Lens.Iso.Iso' a b -> c -> m ()
-- (^^=) :: ('MonadState' a m, 'Fractional' b, 'Integral' c) => 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens' a b -> c -> m ()
-- (^^=) :: ('MonadState' a m, 'Fractional' b, 'Integral' c) => 'Control.Lens.Type.Simple' 'Control.Lens.Traversal.Traversal' a b -> c -> m ()
-- @
(^^=) :: (MonadState a m, Fractional b, Integral c) => SimpleSetting a b -> c -> m ()
l ^^= c = State.modify (l ^^~ c)
{-# INLINE (^^=) #-}
-- | Raise the target(s) of a numerically valued 'Control.Lens.Type.Lens', 'Setter' or 'Control.Lens.Traversal.Traversal' to an arbitrary power
--
-- @
-- (**=) :: ('MonadState' a m, 'Floating' b) => 'Control.Lens.Type.Simple' 'Setter' a b -> b -> m ()
-- (**=) :: ('MonadState' a m, 'Floating' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Iso.Iso' a b -> b -> m ()
-- (**=) :: ('MonadState' a m, 'Floating' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens' a b -> b -> m ()
-- (**=) :: ('MonadState' a m, 'Floating' b) => 'Control.Lens.Type.Simple' 'Control.Lens.Traversal.Traversal' a b -> b -> m ()
-- @
(**=) :: (MonadState a m, Floating b) => SimpleSetting a b -> b -> m ()
l **= b = State.modify (l **~ b)
{-# INLINE (**=) #-}
-- | Modify the target(s) of a 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens', 'Control.Lens.Iso.Iso', 'Setter' or 'Control.Lens.Traversal.Traversal' by taking their logical '&&' with a value
--
-- @
-- (&&=):: 'MonadState' a m => 'Control.Lens.Type.Simple' 'Setter' a 'Bool' -> 'Bool' -> m ()
-- (&&=):: 'MonadState' a m => 'Control.Lens.Type.Simple' 'Control.Lens.Iso.Iso' a 'Bool' -> 'Bool' -> m ()
-- (&&=):: 'MonadState' a m => 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens' a 'Bool' -> 'Bool' -> m ()
-- (&&=):: 'MonadState' a m => 'Control.Lens.Type.Simple' 'Control.Lens.Traversal.Traversal' a 'Bool' -> 'Bool' -> m ()
-- @
(&&=):: MonadState a m => SimpleSetting a Bool -> Bool -> m ()
l &&= b = State.modify (l &&~ b)
{-# INLINE (&&=) #-}
-- | Modify the target(s) of a 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens', 'Iso, 'Setter' or 'Control.Lens.Traversal.Traversal' by taking their logical '||' with a value
--
-- @
-- (||=):: 'MonadState' a m => 'Control.Lens.Type.Simple' 'Setter' a 'Bool' -> 'Bool' -> m ()
-- (||=):: 'MonadState' a m => 'Control.Lens.Type.Simple' 'Control.Lens.Iso.Iso' a 'Bool' -> 'Bool' -> m ()
-- (||=):: 'MonadState' a m => 'Control.Lens.Type.Simple' 'Control.Lens.Type.Lens' a 'Bool' -> 'Bool' -> m ()
-- (||=):: 'MonadState' a m => 'Control.Lens.Type.Simple' 'Control.Lens.Traversal.Traversal' a 'Bool' -> 'Bool' -> m ()
-- @
(||=) :: MonadState a m => SimpleSetting a Bool -> Bool -> m ()
l ||= b = State.modify (l ||~ b)
{-# INLINE (||=) #-}
-- | Run a monadic action, and set all of the targets of a 'Control.Lens.Type.Lens', 'Setter' or 'Control.Lens.Traversal.Traversal' to its result.
--
-- @
-- (\<~) :: 'MonadState' a m => 'Control.Lens.Iso.Iso' a a c d -> m d -> m ()
-- (\<~) :: 'MonadState' a m => 'Control.Lens.Type.Lens' a a c d -> m d -> m ()
-- (\<~) :: 'MonadState' a m => 'Control.Lens.Traversal.Traversal' a a c d -> m d -> m ()
-- (\<~) :: 'MonadState' a m => 'Setter' a a c d -> m d -> m ()
-- @
--
-- As a reasonable mnemonic, this lets you store the result of a monadic action in a lens rather than
-- in a local variable.
--
-- > do foo <- bar
-- > ...
--
-- will store the result in a variable, while
--
-- > do foo <~ bar
-- > ...
--
-- will store the result in a 'Control.Lens.Type.Lens', 'Setter', or 'Control.Lens.Traversal.Traversal'.
(<~) :: MonadState a m => Setting a a c d -> m d -> m ()
l <~ md = md >>= (l .=)
{-# INLINE (<~) #-}
-- | Set with pass-through
--
-- This is useful for chaining assignment without round-tripping through your monad stack.
--
-- @do x <- '_2' <.= ninety_nine_bottles_of_beer_on_the_wall@
--
-- If you do not need a copy of the intermediate result, then using @l .= d@ will avoid unused binding warnings
--
-- @
-- (\<.=) :: 'MonadState' a m => 'Setter' a a c d -> d -> m d
-- (\<.=) :: 'MonadState' a m => 'Control.Lens.Iso.Iso' a a c d -> d -> m d
-- (\<.=) :: 'MonadState' a m => 'Control.Lens.Type.Lens' a a c d -> d -> m d
-- (\<.=) :: 'MonadState' a m => 'Control.Lens.Traversal.Traversal' a a c d -> d -> m d
-- @
(<.=) :: MonadState a m => Setting a a c d -> d -> m d
l <.= d = do
l .= d
return d
{-# INLINE (<.=) #-}
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