edu.neu.ccs.demeterf.lib
Class Option<X>

java.lang.Object
  edu.neu.ccs.demeterf.lib.Option<X>

Direct Known Subclasses:

None, Some

public abstract class Option<X>
extends java.lang.Object

Represents an Optional instance, similar to ML/Haskell Option types. Subclasses Some/None should not be used directly, please Option.some(...) and Option.none() to create them.

Constructor Summary

Option()

Method Summary

abstract <Y> Option<Y>	apply(List.Map<X,Y> m) Apply a function to the contained object in this Option if it exists
abstract X	inner() Get the inner instance that this Option contains
abstract boolean	isSome() Does this Option exist?
static <X> Option<X>	none() Create an Option that is not there (nothing)
static <X> Option<X>	some(X x) Create an Option that exists.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Option

public Option()

Method Detail

some

public static <X> Option<X> some(X x)

Create an Option that exists.

none

public static <X> Option<X> none()

Create an Option that is not there (nothing)

isSome

public abstract boolean isSome()

Does this Option exist?

inner

public abstract X inner()

Get the inner instance that this Option contains

apply

public abstract <Y> Option<Y> apply(List.Map<X,Y> m)

Apply a function to the contained object in this Option if it exists