Safe Haskell | Safe-Inferred |
---|---|
Language | Haskell2010 |
Synopsis
- type ReversedLens s t a b = Optic A_ReversedLens NoIx s t a b
- type ReversedLens' t b = Optic' A_ReversedLens NoIx t b
- data A_ReversedLens :: OpticKind
Formation
type ReversedLens s t a b = Optic A_ReversedLens NoIx s t a b Source #
Type synonym for a type-modifying reversed lens.
type ReversedLens' t b = Optic' A_ReversedLens NoIx t b Source #
Type synonym for a type-preserving reversed lens.
Introduction
There is no canonical introduction form for ReversedLens
, but you can use
re
to construct one from a Lens
:
(\ f g ->re
(lens
f g)) :: (b -> t) -> (b -> s -> a) ->ReversedLens
s t a b
Elimination
A ReversedLens
is a Review
, so you can specialise types to obtain:
review
::ReversedLens'
s a -> a -> s
There is no corresponding optic kind for a backwards
Setter
, but a reversed set
is definable
using re
:
set
.re
::ReversedLens
s t a b -> s -> b -> a
Computation
Subtyping
data A_ReversedLens :: OpticKind Source #
Tag for a reversed lens.