Class Identity<A>

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private A a  
    • Constructor Summary

      Constructors 
      Constructor Description
      Identity​(A a)  
    • Field Detail

      • a

        private final A a
    • Constructor Detail

      • Identity

        public Identity​(A a)
    • Method Detail

      • runIdentity

        public A runIdentity()
        Retrieve the value.
        Returns:
        the value
      • flatMap

        public <B> Identity<B> flatMap​(Fn1<? super A,​? extends Monad<B,​Identity<?>>> f)
        Chain dependent computations that may continue or short-circuit based on previous results.
        Specified by:
        flatMap in interface Monad<A,​Identity<?>>
        Specified by:
        flatMap in interface MonadRec<A,​Identity<?>>
        Type Parameters:
        B - the resulting monad parameter type
        Parameters:
        f - the dependent computation over A
        Returns:
        the new monad instance
      • fmap

        public <B> Identity<B> fmap​(Fn1<? super A,​? extends B> fn)
        Covariantly transmute this functor's parameter using the given mapping function. Generally this method is specialized to return an instance of the class implementing Functor.
        Specified by:
        fmap in interface Applicative<A,​Identity<?>>
        Specified by:
        fmap in interface Functor<A,​Identity<?>>
        Specified by:
        fmap in interface Monad<A,​Identity<?>>
        Specified by:
        fmap in interface MonadRec<A,​Identity<?>>
        Specified by:
        fmap in interface Traversable<A,​Identity<?>>
        Type Parameters:
        B - the new parameter type
        Parameters:
        fn - the mapping function
        Returns:
        a functor over B (the new parameter type)
      • pure

        public <B> Identity<B> pure​(B b)
        Lift the value b into this applicative functor.
        Specified by:
        pure in interface Applicative<A,​Identity<?>>
        Specified by:
        pure in interface Monad<A,​Identity<?>>
        Specified by:
        pure in interface MonadRec<A,​Identity<?>>
        Type Parameters:
        B - the type of the returned applicative's parameter
        Parameters:
        b - the value
        Returns:
        an instance of this applicative over b
      • zip

        public <B> Identity<B> zip​(Applicative<Fn1<? super A,​? extends B>,​Identity<?>> appFn)
        Given another instance of this applicative over a mapping function, "zip" the two instances together using whatever application semantics the current applicative supports.
        Specified by:
        zip in interface Applicative<A,​Identity<?>>
        Specified by:
        zip in interface Monad<A,​Identity<?>>
        Specified by:
        zip in interface MonadRec<A,​Identity<?>>
        Type Parameters:
        B - the resulting applicative parameter type
        Parameters:
        appFn - the other applicative instance
        Returns:
        the mapped applicative
      • lazyZip

        public <B> Lazy<Identity<B>> lazyZip​(Lazy<? extends Applicative<Fn1<? super A,​? extends B>,​Identity<?>>> lazyAppFn)
        Given a lazy instance of this applicative over a mapping function, "zip" the two instances together using whatever application semantics the current applicative supports. This is useful for applicatives that support lazy evaluation and early termination.
        Specified by:
        lazyZip in interface Applicative<A,​Identity<?>>
        Specified by:
        lazyZip in interface Monad<A,​Identity<?>>
        Specified by:
        lazyZip in interface MonadRec<A,​Identity<?>>
        Type Parameters:
        B - the resulting applicative parameter type
        Parameters:
        lazyAppFn - the lazy other applicative instance
        Returns:
        the mapped applicative
        See Also:
        Maybe, Either
      • discardL

        public <B> Identity<B> discardL​(Applicative<B,​Identity<?>> appB)
        Sequence both this Applicative and appB, discarding this Applicative's result and returning appB. This is generally useful for sequentially performing side-effects.
        Specified by:
        discardL in interface Applicative<A,​Identity<?>>
        Specified by:
        discardL in interface Monad<A,​Identity<?>>
        Specified by:
        discardL in interface MonadRec<A,​Identity<?>>
        Type Parameters:
        B - the type of the returned Applicative's parameter
        Parameters:
        appB - the other Applicative
        Returns:
        appB
      • discardR

        public <B> Identity<A> discardR​(Applicative<B,​Identity<?>> appB)
        Sequence both this Applicative and appB, discarding appB's result and returning this Applicative. This is generally useful for sequentially performing side-effects.
        Specified by:
        discardR in interface Applicative<A,​Identity<?>>
        Specified by:
        discardR in interface Monad<A,​Identity<?>>
        Specified by:
        discardR in interface MonadRec<A,​Identity<?>>
        Type Parameters:
        B - the type of appB's parameter
        Parameters:
        appB - the other Applicative
        Returns:
        this Applicative
      • traverse

        public <B,​App extends Applicative<?,​App>,​TravB extends Traversable<B,​Identity<?>>,​AppTrav extends Applicative<TravB,​App>> AppTrav traverse​(Fn1<? super A,​? extends Applicative<B,​App>> fn,
                                                                                                                                                                                       Fn1<? super TravB,​? extends AppTrav> pure)
        Apply fn to each element of this traversable from left to right, and collapse the results into a single resulting applicative, potentially with the assistance of the applicative's pure function.
        Specified by:
        traverse in interface Traversable<A,​Identity<?>>
        Type Parameters:
        B - the resulting element type
        App - the result applicative type
        TravB - this Traversable instance over B
        AppTrav - the full inferred resulting type from the traversal
        Parameters:
        fn - the function to apply
        pure - the applicative pure function
        Returns:
        the traversed Traversable, wrapped inside an applicative
      • equals

        public boolean equals​(java.lang.Object other)
        Overrides:
        equals in class java.lang.Object
      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class java.lang.Object
      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object