scala

object None

[source: scala/None.scala]

case object None
extends Option[Nothing]
This case object represents non-existent values.
Author
Martin Odersky
Version
1.0, 16/07/2003
Method Summary
def get : Nothing
get the value of this option. @requires that the option is nonEmpty.
def isEmpty : Boolean
True if the option is the None value, false otherwise.
override def productArity : Int
return k for a product A(x_1,...,x_k)
override def productElement (arg0 : Int) : Any
for a product A(x_1,...,x_k), returns x_(n+1) for 0 <= n < k
override def productPrefix : java.lang.String
By default the empty string. Implementations may override this method in order to prepend a string prefix to the result of the toString methods.
protected def readResolve : AnyRef
override final def toString : java.lang.String
Methods inherited from Option
isDefined, get, getOrElse, map, flatMap, filter, foreach, orElse, elements, toList, toRight, toLeft
Methods inherited from AnyRef
getClass, hashCode, equals, clone, notify, notifyAll, wait, wait, wait, finalize, ==, !=, eq, ne, synchronized
Methods inherited from Any
==, !=, isInstanceOf, asInstanceOf
Method Details
def isEmpty : Boolean
True if the option is the None value, false otherwise.
Overrides
Option.isEmpty

def get : Nothing
get the value of this option. @requires that the option is nonEmpty.
Throws
Predef.NoSuchElementException - if the option is empty.
Overrides
Option.get

override final def toString : java.lang.String

override def productPrefix : java.lang.String
By default the empty string. Implementations may override this method in order to prepend a string prefix to the result of the toString methods.

override def productArity : Int
return k for a product A(x_1,...,x_k)

override def productElement(arg0 : Int) : Any
for a product A(x_1,...,x_k), returns x_(n+1) for 0 <= n < k
Parameters
n - the index of the element to return
Throws
IndexOutOfBoundsException -
Returns
The element n elements after the first element

protected def readResolve : AnyRef