Class Choice3<A,B,C>

java.lang.Object
com.jnape.palatable.lambda.adt.choice.Choice3<A,B,C>
Type Parameters:
A - the first possible type
B - the second possible type
C - the third possible type
All Implemented Interfaces:
CoProduct3<A, B, C, Choice3<A,B,C>>, Applicative<C, Choice3<A,B,?>>, Bifunctor<B, C, Choice3<A,?,?>>, BoundedBifunctor<B, C, Object, Object, Choice3<A,?,?>>, Functor<C, Choice3<A,B,?>>, Monad<C, Choice3<A,B,?>>, MonadRec<C, Choice3<A,B,?>>, Traversable<C, Choice3<A,B,?>>
Direct Known Subclasses:
Choice3._A, Choice3._B, Choice3._C
public abstract class Choice3<A,B,C> extends Object implements CoProduct3<A, B, C, Choice3<A,B,C>>, MonadRec<C, Choice3<A,B,?>>, Bifunctor<B, C, Choice3<A,?,?>>, Traversable<C, Choice3<A,B,?>>
Canonical ADT representation of CoProduct3.
See Also:

  • Constructor Details

    • Choice3

      private Choice3()

  • Method Details

    • project

      public Tuple3<Maybe<A>,Maybe<B>,Maybe<C>> project()
      Specialize this choice's projection to a Tuple3.
      Specified by:
      project in interface CoProduct3<A, B, C, Choice3<A,B,C>>
      Returns:
      a Tuple3
      See Also:

    • diverge

      public final <D> Choice4<A,B,C,D> diverge()
      Diverge this coproduct by introducing another possible type that it could represent.
      Specified by:
      diverge in interface CoProduct3<A, B, C, Choice3<A,B,C>>
      Type Parameters:
      D - the additional possible type of this coproduct
      Returns:
      a CoProduct4<A, B, C, D>
      See Also:

    • converge

      public final Choice2<A,B> converge(Fn1<? super C, ? extends CoProduct2<A,B,?>> convergenceFn)
      Converge this coproduct down to a lower order coproduct by mapping the last possible type into an earlier possible type. This is the categorical dual of CoProduct2.diverge(), which introduces the type C and raises the order from 2 to 3.

      The following laws hold for any two coproducts of single order difference:

      • Cancellation: coProductN.diverge().converge(CoProductN::a) == coProductN
      Specified by:
      converge in interface CoProduct3<A, B, C, Choice3<A,B,C>>
      Parameters:
      convergenceFn - function from last possible type to earlier type
      Returns:
      a CoProduct2<A, B>

    • fmap

      public final <D> Choice3<A,B,D> fmap(Fn1<? super C, ? extends D> 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,B>
      Specified by:
      fmap in interface Functor<A,B>
      Specified by:
      fmap in interface Monad<A,B>
      Specified by:
      fmap in interface MonadRec<A,B>
      Specified by:
      fmap in interface Traversable<A,B>
      Type Parameters:
      D - the new parameter type
      Parameters:
      fn - the mapping function
      Returns:
      a functor over B (the new parameter type)

    • biMapL

      public final <D> Choice3<A,D,C> biMapL(Fn1<? super B, ? extends D> fn)
      Covariantly map over the left parameter.
      Specified by:
      biMapL in interface Bifunctor<A,B,C>
      Specified by:
      biMapL in interface BoundedBifunctor<B, C, Object, Object, Choice3<A,?,?>>
      Type Parameters:
      D - the new left parameter type
      Parameters:
      fn - the mapping function
      Returns:
      a bifunctor over C (the new left parameter) and B (the same right parameter)

    • biMapR

      public final <D> Choice3<A,B,D> biMapR(Fn1<? super C, ? extends D> fn)
      Covariantly map over the right parameter. For all bifunctors that are also functors, it should hold that biMapR(f) == fmap(f).
      Specified by:
      biMapR in interface Bifunctor<A,B,C>
      Specified by:
      biMapR in interface BoundedBifunctor<B, C, Object, Object, Choice3<A,?,?>>
      Type Parameters:
      D - the new right parameter type
      Parameters:
      fn - the mapping function
      Returns:
      a bifunctor over A (the same left parameter) and C (the new right parameter)

    • biMap

      public final <D,E> Choice3<A,D,E> biMap(Fn1<? super B, ? extends D> lFn, Fn1<? super C, ? extends E> rFn)
      Dually map covariantly over both the left and right parameters. This is isomorphic to biMapL(lFn).biMapR(rFn).
      Specified by:
      biMap in interface Bifunctor<A,B,C>
      Specified by:
      biMap in interface BoundedBifunctor<B, C, Object, Object, Choice3<A,?,?>>
      Type Parameters:
      D - the new left parameter type
      E - the new right parameter type
      Parameters:
      lFn - the left parameter mapping function
      rFn - the right parameter mapping function
      Returns:
      a bifunctor over C (the new left parameter type) and D (the new right parameter type)

    • pure

      public <D> Choice3<A,B,D> pure(D d)
      Lift the value b into this applicative functor.
      Specified by:
      pure in interface Applicative<A,B>
      Specified by:
      pure in interface Monad<A,B>
      Specified by:
      pure in interface MonadRec<A,B>
      Type Parameters:
      D - the type of the returned applicative's parameter
      Parameters:
      d - the value
      Returns:
      an instance of this applicative over b

    • zip

      public <D> Choice3<A,B,D> zip(Applicative<Fn1<? super C, ? extends D>, Choice3<A,B,?>> 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,B>
      Specified by:
      zip in interface Monad<A,B>
      Specified by:
      zip in interface MonadRec<A,B>
      Type Parameters:
      D - the resulting applicative parameter type
      Parameters:
      appFn - the other applicative instance
      Returns:
      the mapped applicative

    • lazyZip

      public <D> Lazy<Choice3<A,B,D>> lazyZip(Lazy<? extends Applicative<Fn1<? super C, ? extends D>, Choice3<A,B,?>>> 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,B>
      Specified by:
      lazyZip in interface Monad<A,B>
      Specified by:
      lazyZip in interface MonadRec<A,B>
      Type Parameters:
      D - the resulting applicative parameter type
      Parameters:
      lazyAppFn - the lazy other applicative instance
      Returns:
      the mapped applicative
      See Also:

    • discardL

      public <D> Choice3<A,B,D> discardL(Applicative<D, Choice3<A,B,?>> 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,B>
      Specified by:
      discardL in interface Monad<A,B>
      Specified by:
      discardL in interface MonadRec<A,B>
      Type Parameters:
      D - the type of the returned Applicative's parameter
      Parameters:
      appB - the other Applicative
      Returns:
      appB

    • discardR

      public <D> Choice3<A,B,C> discardR(Applicative<D, Choice3<A,B,?>> 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,B>
      Specified by:
      discardR in interface Monad<A,B>
      Specified by:
      discardR in interface MonadRec<A,B>
      Type Parameters:
      D - the type of appB's parameter
      Parameters:
      appB - the other Applicative
      Returns:
      this Applicative

    • flatMap

      public <D> Choice3<A,B,D> flatMap(Fn1<? super C, ? extends Monad<D, Choice3<A,B,?>>> f)
      Chain dependent computations that may continue or short-circuit based on previous results.
      Specified by:
      flatMap in interface Monad<A,B>
      Specified by:
      flatMap in interface MonadRec<A,B>
      Type Parameters:
      D - the resulting monad parameter type
      Parameters:
      f - the dependent computation over A
      Returns:
      the new monad instance

    • trampolineM

      public <D> Choice3<A,B,D> trampolineM(Fn1<? super C, ? extends MonadRec<RecursiveResult<C,D>, Choice3<A,B,?>>> fn)
      Given some operation yielding a RecursiveResult inside this MonadRec, internally trampoline the operation until it yields a termination instruction.

      Stack-safety depends on implementations guaranteeing that the growth of the call stack is a constant factor independent of the number of invocations of the operation. For various examples of how this can be achieved in stereotypical circumstances, see the referenced types.

      Specified by:
      trampolineM in interface MonadRec<A,B>
      Type Parameters:
      D - the ultimate resulting carrier type
      Parameters:
      fn - the function to internally trampoline
      Returns:
      the trampolined MonadRec
      See Also:

    • traverse

      public <D, App extends Applicative<?,App>, TravB extends Traversable<D, Choice3<A,B,?>>, AppTrav extends Applicative<TravB,App>> AppTrav traverse(Fn1<? super C, ? extends Applicative<D,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,B>
      Type Parameters:
      D - 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

    • a

      public static <A,B,C> Choice3<A,B,C> a(A a)
      Static factory method for wrapping a value of type A in a Choice3.
      Type Parameters:
      A - the first possible type
      B - the second possible type
      C - the third possible type
      Parameters:
      a - the value
      Returns:
      the wrapped value as a Choice3<A, B, C>

    • b

      public static <A,B,C> Choice3<A,B,C> b(B b)
      Static factory method for wrapping a value of type A in a Choice3.
      Type Parameters:
      A - the first possible type
      B - the second possible type
      C - the third possible type
      Parameters:
      b - the value
      Returns:
      the wrapped value as a Choice3<A, B, C>

    • c

      public static <A,B,C> Choice3<A,B,C> c(C c)
      Static factory method for wrapping a value of type A in a Choice3.
      Type Parameters:
      A - the first possible type
      B - the second possible type
      C - the third possible type
      Parameters:
      c - the value
      Returns:
      the wrapped value as a Choice3<A, B, C>

    • pureChoice

      public static <A,B> Pure<Choice3<A,B,?>> pureChoice()
      The canonical Pure instance for Choice3.
      Type Parameters:
      A - the first possible type
      B - the second possible type
      Returns:
      the Pure instance