Trait garfield::applicative::Applicative

pub trait Applicative: Functor {
    fn pure(a: Self::Inner) -> Self::Wrapped<Self::Inner>;
    fn seq<F: Fn(Self::Inner) -> B, B>(
        f: F,
        fa: Self::Wrapped<Self::Inner>
    ) -> Self::Wrapped<B>;
    fn lift_a2<F: Fn(Self::Inner, B) -> C, B, C>(
        f: F,
        fa: Self::Wrapped<Self::Inner>,
        fb: Self::Wrapped<B>
    ) -> Self::Wrapped<C>;
}

A functor with application, providing operations to

• Embed pure expressions using Applicative::pure
• Sequence computations and combine their results using Applicative::lift_a2

Required Methods

fn pure(a: Self::Inner) -> Self::Wrapped<Self::Inner>

Lift a value into a functor

In Haskell speak this translates to, pure :: (Functor f) => a -> f a

fn seq<F: Fn(Self::Inner) -> B, B>(
    f: F,
    fa: Self::Wrapped<Self::Inner>
) -> Self::Wrapped<B>

Run a computation inside a functor.

In Haskell speak this translates to, (<*>) :: (Functor f) => f (a -> b) -> f a -> f b

fn lift_a2<F: Fn(Self::Inner, B) -> C, B, C>(
    f: F,
    fa: Self::Wrapped<Self::Inner>,
    fb: Self::Wrapped<B>
) -> Self::Wrapped<C>

Lift a binary function into actions

lift_a2 :: (a -> b -> c) -> f a -> f b -> f c

Implementations on Foreign Types

impl<A> Applicative for Option<A>

fn pure(val: Self::Inner) -> Self::Wrapped<A>

fn seq<F: Fn(Self::Inner) -> B, B>(
    f: F,
    fa: Self::Wrapped<Self::Inner>
) -> Self::Wrapped<B>

fn lift_a2<F: Fn(Self::Inner, B) -> C, B, C>(
    f: F,
    fa: Self::Wrapped<Self::Inner>,
    fb: Self::Wrapped<B>
) -> Self::Wrapped<C>

impl<T, E> Applicative for Result<T, E>

fn pure(val: Self::Inner) -> Self::Wrapped<Self::Inner>

fn lift_a2<F: Fn(Self::Inner, B) -> C, B, C>(
    f: F,
    fa: Self::Wrapped<Self::Inner>,
    fb: Self::Wrapped<B>
) -> Self::Wrapped<C>

fn seq<F: Fn(Self::Inner) -> B, B>(
    f: F,
    fa: Self::Wrapped<Self::Inner>
) -> Self::Wrapped<B>

Implementors