lens-5.2.3: Lenses, Folds and Traversals

Copyright | (C) 2012-16 Edward Kmett
License | BSD-style (see the file LICENSE)
Maintainer | Edward Kmett <ekmett@gmail.com>
Stability | provisional
Portability | non-portable
Safe Haskell | Trustworthy
Language | Haskell2010

Control.Lens.Empty

Description

# Documentation

class AsEmpty a where #

Minimal complete definition

Nothing

Methods

_Empty :: Prism' a () #

    >>> isn't _Empty [1,2,3]
    True

default _Empty :: (Monoid a, Eq a) => Prism' a () #

#### Instances

Instances details

AsEmpty All # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' All () #
AsEmpty Any # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' Any () #
AsEmpty Event # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' Event () #
AsEmpty ByteString # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' ByteString () #
AsEmpty ByteString # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' ByteString () #
AsEmpty IntSet # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' IntSet () #
AsEmpty Ordering # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' Ordering () #
AsEmpty Text # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' Text () #
AsEmpty Text # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' Text () #
AsEmpty () # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' () () #
AsEmpty (ZipList a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (ZipList a) () #
AsEmpty (First a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (First a) () #
AsEmpty (Last a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Last a) () #
AsEmpty a => AsEmpty (Dual a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Dual a) () #
(Eq a, Num a) => AsEmpty (Product a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Product a) () #
(Eq a, Num a) => AsEmpty (Sum a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Sum a) () #
AsEmpty (IntMap a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (IntMap a) () #
AsEmpty (Seq a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Seq a) () #
AsEmpty (Set a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Set a) () #
AsEmpty (HashSet a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (HashSet a) () #
AsEmpty (Vector a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Vector a) () #
Storable a => AsEmpty (Vector a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Vector a) () #
Unbox a => AsEmpty (Vector a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Vector a) () #
AsEmpty (Maybe a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Maybe a) () #
AsEmpty [a] # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' [a] () #
AsEmpty (Map k a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (Map k a) () #
AsEmpty (HashMap k a) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (HashMap k a) () #
(AsEmpty a, AsEmpty b) => AsEmpty (a, b) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (a, b) () #
(AsEmpty a, AsEmpty b, AsEmpty c) => AsEmpty (a, b, c) # |
Instance details Defined in Control.Lens.Empty Methods _Empty :: Prism' (a, b, c) () #

pattern Empty :: AsEmpty s => s #