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1. runMaybeS :: forall (m :: Type -> Type) a b . (Functor m, Monad m) => Automaton (MaybeT m) a b -> Automaton m a (Maybe b)

   automaton	Data.Automaton.Trans.Maybe

   Remove the MaybeT layer by outputting Nothing when the exception occurs. The current state is then tested again on the next input.

2. runMaybeT :: MaybeT (m :: Type -> Type) a -> m (Maybe a)

   automaton	Data.Automaton.Trans.Maybe

   No documentation available.

3. untilMaybe :: forall (m :: Type -> Type) a b . Monad m => Automaton m a b -> Automaton m b Bool -> Automaton (MaybeT m) a b

   automaton	Data.Automaton.Trans.Maybe

   Run the first automaton until the second one produces True from the output of the first.

4. readMaybe :: Read a => String -> Maybe a

   base-prelude	BasePrelude

   Parse a string using the Read instance. Succeeds if there is exactly one valid result.

   >>> readMaybe "123" :: Maybe Int
   Just 123
   

   >>> readMaybe "hello" :: Maybe Int
   Nothing
   

5. eqMaybeE :: IsSql92ExpressionSyntax expr => expr -> expr -> expr -> expr

   beam-core	Database.Beam.Backend.SQL.SQL92

   Compare the first and second argument for nullable equality, if they are both not null, return the result of the third expression Some backends, like beam-postgres totally ignore the third result, because all equality there is sensible.

6. neqMaybeE :: IsSql92ExpressionSyntax expr => expr -> expr -> expr -> expr

   beam-core	Database.Beam.Backend.SQL.SQL92

   Compare the first and second argument for nullable equality, if they are both not null, return the result of the third expression Some backends, like beam-postgres totally ignore the third result, because all equality there is sensible.

7. type OneToMaybe be (db :: Type -> Type -> Type) s (tbl :: Type -> Type -> Type) (rel :: Type -> Type -> Type) = OneToManyOptional be db s tbl rel

   beam-core	Database.Beam.Query

   Synonym of OneToManyOptional. Useful for giving more meaningful types, when the relationship is meant to be one-to-one.

8. class BeamSqlBackend be => SqlDeconstructMaybe be a nonNullA s | a s -> be, a -> nonNullA, a -> s, nonNullA -> s

   beam-core	Database.Beam.Query

   Type class for anything which can be checked for null-ness. This includes 'QExpr (Maybe a)' as well as Tables or PrimaryKeys over 'Nullable QExpr'.

9. fromMaybe_ :: BeamSqlBackend be => QGenExpr ctxt be s a -> QGenExpr ctxt be s (Maybe a) -> QGenExpr ctxt be s a

   beam-core	Database.Beam.Query

   Convert a Maybe value to a concrete value, by suppling a default

10. limitMaybe_ :: forall s a be (db :: (Type -> Type) -> Type) . (Projectible be a, ThreadRewritable (QNested s) a) => Maybe Integer -> Q be db (QNested s) a -> Q be db s (WithRewrittenThread (QNested s) s a)

    beam-core	Database.Beam.Query

    Conditionally limit the number of results returned by a query.

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