nothing -package:gi-gtk
Analogous to
Nothing and equivalent to
mzero
nothing :: Prism' (Maybe a) ()
A prism on the
Nothing element of a
Maybe.
Match nothing, universal rejector.
>>> prove $ \(s :: SString) -> sNot (s `match` nothing)
Q.E.D.
Record with polymorphic phantom type of SQL null value. Semantics of
comparing is unsafe.
Assert that some value is Nothing.
A predicate checking if the input is Nothing
>>> Nothing `shouldSatisfy` P.nothing
This doesn't modify the config in any way. It's just here for your
initial config because Haskell doesn't allow empty do-blocks. Feel
free to delete it once you've added other stuff.
A Predicate that accepts
Maybe values of
Nothing. Unlike
eq, this doesn't require
Eq or
Show instances.
>>> accept nothing Nothing
True
>>> accept nothing (Just "something")
False
base Prelude Data.Maybe GHC.Maybe,
hedgehog Hedgehog.Internal.Prelude,
ghc GHC.Data.Strict GHC.Prelude.Basic,
base-compat Prelude.Compat,
strict Data.Strict.Maybe,
protolude Protolude,
haskell-gi-base Data.GI.Base.ShortPrelude,
relude Relude.Monad.Reexport,
rio RIO.Prelude.Types,
base-prelude BasePrelude BasePrelude.DataTypes,
classy-prelude ClassyPrelude,
numeric-prelude NumericPrelude NumericPrelude.Base,
Cabal-syntax Distribution.Compat.Prelude,
basic-prelude CorePrelude,
universum Universum.Monad.Reexport,
ihaskell IHaskellPrelude,
basement Basement.Compat.Base Basement.Imports,
numhask NumHask.Prelude,
clash-prelude Clash.HaskellPrelude,
foundation Foundation,
ghc-lib-parser GHC.Data.Strict GHC.Prelude.Basic,
prelude-compat Prelude2010,
ghc-internal GHC.Internal.Data.Maybe GHC.Internal.Maybe,
dimensional Numeric.Units.Dimensional.Prelude,
rebase Rebase.Prelude,
quaalude Essentials,
mixed-types-num Numeric.MixedTypes.PreludeHiding,
xmonad-contrib XMonad.Config.Prime,
yaya Yaya.Pattern,
constrained-categories Control.Category.Constrained.Prelude Control.Category.Hask,
copilot-language Copilot.Language.Prelude,
incipit-base Incipit.Base,
LambdaHack Game.LambdaHack.Core.Prelude,
cabal-install-solver Distribution.Solver.Compat.Prelude,
faktory Faktory.Prelude,
protobuf-simple Data.ProtoBufInt,
strict-base-types Data.Maybe.Strict,
vcr Imports,
verset Verset,
yesod-paginator Yesod.Paginator.Prelude,
distribution-opensuse OpenSuse.Prelude,
termonad Termonad.Prelude
nothing_ :: Traversal' (Maybe a) ()
Traversal on the
Nothing element of a
Maybe.
Throw an exception with an error string associated with an
unsuccessful return code, otherwise return unit.
Return the error string associated with an unsuccessful return code,
otherwise Nothing