nothing -package:lens-family-core

Analogous to Nothing and equivalent to mzero

A prism on the Nothing element of a Maybe.

NULL value.

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.

Nothing bound to the Maybe Int type encoded as an Expr. This is an alias to nothingInt.

Traversal on the Nothing element of a Maybe.

Gets the nothing action. This is an action that does nothing and where activating it always fails.

Return either a 'QExpr (Maybe x)' representing Nothing or a nullable Table or PrimaryKey filled with Nothing.

>>> runTP nothingBetweenZeroAndOne
Lemma: nothingBetweenZeroAndOne         Q.E.D.
[Proven] nothingBetweenZeroAndOne :: Ɐm ∷ Nat → Bool

The Opaleye analogue of Nothing.

The Opaleye analogue of const Nothing. Can be useful to avoid type inference problems, because it doesn't pick up a type class constraint.