public Maybe <Pair <A, B> > Zip <A, B>(Maybe <A> maybe, Maybe <B> other)
{
return(maybe.Cata(
Maybe.Nothing <Pair <A, B> >,
a => other.Cata(
Maybe.Nothing <Pair <A, B> >,
b => Maybe.Just(Pair.Create(a, b)))));
}
public static IEnumerable <A> Enumerable <A>(this Maybe <A> maybe)
{
return(maybe.Cata(System.Linq.Enumerable.Empty <A>, a => a.PureEnumerable()));
}
public static Validation <X, A> Validation <X, A>(this Maybe <A> maybe, Func <X> fail)
{
return(maybe.Cata(() => Jib.Validation.Failure <X, A>(fail()), Jib.Validation.Success <X, A>));
}
public static bool JustTest <A>(this Maybe <A> maybe, Func <A, bool> predicate)
{
return(maybe.Cata(() => false, predicate));
}
public bool Eq(Maybe <A> t1, Maybe <A> t2)
{
return(t1.Cata(() => t2.Cata(() => true, a2 => false), a1 => t2.Cata(() => false, a2 => teq.Eq(a1, a2))));
}
public static Either <X, A> Either <X, A>(this Maybe <A> maybe, Func <X> left)
{
return(maybe.Cata(() => Jib.Either.Left <X, A>((left())), Jib.Either.Right <X, A>));
}
public static Maybe <A> Where <A>(this Maybe <A> maybe, Func <A, bool> predicate)
{
return(maybe.Cata(Maybe.Nothing <A>, a => predicate(a) ? maybe : Maybe.Nothing <A>()));
}
public static Maybe <B> Bind <A, B>(this Maybe <A> maybe, Func <A, Maybe <B> > f)
{
return(maybe.Cata(Maybe.Nothing <B>, f));
}
public static void CataVoid <A>(this Maybe <A> maybe, Action nothing, Action <A> just)
{
maybe.Cata(Unit.Func(nothing), Unit.Func(just));
}
public Maybe <B> Map <A, B>(Maybe <A> maybe, Func <A, B> f)
{
return(maybe.Cata(Maybe.Nothing <B>, a => Maybe.Just(f(a))));
}
public static IEnumerable <Maybe <B> > TraverseEnumerable <A, B>(this Maybe <A> maybe, Func <A, IEnumerable <B> > f)
{
return(maybe.Cata(() => Maybe.Nothing <B>().PureEnumerable(), a => f(a).Select(Maybe.Just)));
}
public static Future <Maybe <A> > SequenceFuture <A>(this Maybe <Future <A> > maybe)
{
return(maybe.Cata(() => Maybe.Nothing <A>().PureFuture(), a => a.Map(Maybe.Just)));
}
public static IEnumerable <Maybe <A> > SequenceEnumerable <A>(this Maybe <IEnumerable <A> > maybe)
{
return(maybe.Cata(() => Maybe.Nothing <A>().PureEnumerable(), a => a.Select(Maybe.Just)));
}
