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Type Members

class WithFilter extends AnyRef

We need a whole WithFilter class to honor the "doesn't create a new collection" contract even though it seems unlikely to matter much in a collection with max size 1.

Value Members

def !=(arg0: AnyRef): Boolean

attributes: final
definition classes: AnyRef
def !=(arg0: Any): Boolean

o != arg0 is the same as !(o == (arg0)).

o != arg0 is the same as !(o == (arg0)).
arg0
the object to compare against this object for dis-equality.
returns
false if the receiver object is equivalent to the argument; true otherwise.
attributes: final
definition classes: Any
def ##(): Int

attributes: final
definition classes: AnyRef → Any
def $asInstanceOf[T0](): T0

attributes: final
definition classes: AnyRef
def $isInstanceOf[T0](): Boolean

attributes: final
definition classes: AnyRef
def ==(arg0: AnyRef): Boolean

o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).

o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).
arg0
the object to compare against this object for equality.
returns
true if the receiver object is equivalent to the argument; false otherwise.
attributes: final
definition classes: AnyRef
def ==(arg0: Any): Boolean

o == arg0 is the same as o.equals(arg0).

o == arg0 is the same as o.equals(arg0).
arg0
the object to compare against this object for equality.
returns
true if the receiver object is equivalent to the argument; false otherwise.
attributes: final
definition classes: Any
def asInstanceOf[T0]: T0

This method is used to cast the receiver object to be of type T0.

This method is used to cast the receiver object to be of type T0.
Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expressionList(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested typed.
returns
the receiver object.
attributes: final
definition classes: Any
def canEqual(arg0: Any): Boolean

A method that should be called from every well-designed equals method that is open to be overridden in a subclass.

A method that should be called from every well-designed equals method that is open to be overridden in a subclass. See Programming in Scala, Chapter 28 for discussion and design.
definition classes: None → Equals
def clone(): AnyRef

This method creates and returns a copy of the receiver object.

This method creates and returns a copy of the receiver object.
The default implementation of the clone method is platform dependent.
returns
a copy of the receiver object.
attributes: protected
definition classes: AnyRef
def collect[B](pf: PartialFunction[A, B]): Option[B]

If the given partial function pf is defined for the option's value, apply it to the value.

If the given partial function pf is defined for the option's value, apply it to the value. Otherwise, None.
pf
the partial function.
definition classes: Option
def eq(arg0: AnyRef): Boolean

This method is used to test whether the argument (arg0) is a reference to the receiver object (this).

This method is used to test whether the argument (arg0) is a reference to the receiver object (this).
The eq method implements an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation] on non-null instances of AnyRef: * It is reflexive: for any non-null instance x of type AnyRef, x.eq(x) returns true. * It is symmetric: for any non-null instances x and y of type AnyRef, x.eq(y) returns true if and only if y.eq(x) returns true. * It is transitive: for any non-null instances x, y, and z of type AnyRef if x.eq(y) returns true and y.eq(z) returns true, then x.eq(z) returns true.
Additionally, the eq method has three other properties. * It is consistent: for any non-null instances x and y of type AnyRef, multiple invocations of x.eq(y) consistently returns true or consistently returns false. * For any non-null instance x of type AnyRef, x.eq(null) and null.eq(x) returns false. * null.eq(null) returns true.
When overriding the equals or hashCode methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2), they should be equal to each other (o1 == o2) and they should hash to the same value (o1.hashCode == o2.hashCode).
arg0
the object to compare against this object for reference equality.
returns
true if the argument is a reference to the receiver object; false otherwise.
attributes: final
definition classes: AnyRef
def equals(arg0: Any): Boolean

This method is used to compare the receiver object (this) with the argument object (arg0) for equivalence.

This method is used to compare the receiver object (this) with the argument object (arg0) for equivalence.
The default implementations of this method is an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation]: * It is reflexive: for any instance x of type Any, x.equals(x) should return true. * It is symmetric: for any instances x and y of type Any, x.equals(y) should return true if and only if y.equals(x) returns true. * It is transitive: for any instances x, y, and z of type AnyRef if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
If you override this method, you should verify that your implementation remains an equivalence relation. Additionally, when overriding this method it is often necessary to override hashCode to ensure that objects that are "equal" (o1.equals(o2) returns true) hash to the same scala.Int (o1.hashCode.equals(o2.hashCode)).
arg0
the object to compare against this object for equality.
returns
true if the receiver object is equivalent to the argument; false otherwise.
definition classes: AnyRef → Any
def exists(p: (A) ⇒ Boolean): Boolean

If the option is nonempty, p(value), otherwise false.

If the option is nonempty, p(value), otherwise false.
p
the predicate to test
definition classes: Option
def filter(p: (A) ⇒ Boolean): Option[A]

If the option is nonempty and the given predicate p yields false on its value, return None.

If the option is nonempty and the given predicate p yields false on its value, return None. Otherwise return the option value itself.
p
the predicate used for testing.
definition classes: Option
def finalize(): Unit

This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.

This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.
The details of when and if the finalize method are invoked, as well as the interaction between finalizeand non-local returns and exceptions, are all platform dependent.
attributes: protected
definition classes: AnyRef
def flatMap[B](f: (A) ⇒ Option[B]): Option[B]

If the option is nonempty, return a function applied to its value.

If the option is nonempty, return a function applied to its value. Otherwise return None.
f
the function to apply
definition classes: Option
def foreach[U](f: (A) ⇒ U): Unit

Apply the given procedure f to the option's value, if it is nonempty.

Apply the given procedure f to the option's value, if it is nonempty. Do nothing if it is empty.
f
the procedure to apply.
definition classes: Option
def get: Nothing

get the value of this option.

get the value of this option.
definition classes: None → Option
def getClass(): java.lang.Class[_ <: java.lang.Object]

Returns a representation that corresponds to the dynamic class of the receiver object.

Returns a representation that corresponds to the dynamic class of the receiver object.
The nature of the representation is platform dependent.
returns
a representation that corresponds to the dynamic class of the receiver object.
attributes: final
definition classes: AnyRef
def getOrElse[B >: A](default: ⇒ B): B

If the option is nonempty return its value, otherwise return the result of evaluating a default expression.

If the option is nonempty return its value, otherwise return the result of evaluating a default expression.
default
the default expression.
definition classes: Option
def hashCode(): Int

Returns a hash code value for the object.

Returns a hash code value for the object.
The default hashing algorithm is platform dependent.
Note that it is allowed for two objects to have identical hash codes (o1.hashCode.equals(o2.hashCode)) yet not be equal (o1.equals(o2) returns false). A degenerate implementation could always return 0. However, it is required that if two objects are equal (o1.equals(o2) returns true) that they have identical hash codes (o1.hashCode.equals(o2.hashCode)). Therefore, when overriding this method, be sure to verify that the behavior is consistent with the equals method.
returns
the hash code value for the object.
definition classes: AnyRef → Any
def isDefined: Boolean

True if the option is a Some(.

True if the option is a Some(...) false otherwise.
definition classes: Option
def isEmpty: Boolean

True if the option is the None value, false otherwise.

True if the option is the None value, false otherwise.
definition classes: None → Option
def isInstanceOf[T0]: Boolean

This method is used to test whether the dynamic type of the receiver object is T0.

This method is used to test whether the dynamic type of the receiver object is T0.
Note that the test result of the test is modulo Scala's erasure semantics. Therefore the expression1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested typed.
returns
true if the receiver object is an instance of erasure of type T0; false otherwise.
attributes: final
definition classes: Any
def iterator: Iterator[A]

An singleton iterator returning the option's value if it is nonempty or the empty iterator if the option is empty.

An singleton iterator returning the option's value if it is nonempty or the empty iterator if the option is empty.
definition classes: Option
def map[B](f: (A) ⇒ B): Option[B]

If the option is nonempty, return a function applied to its value, wrapped in a Some i.

If the option is nonempty, return a function applied to its value, wrapped in a Some i.e. Some(f(this.get)). Otherwise return None.
f
the function to apply
definition classes: Option
def ne(arg0: AnyRef): Boolean

o.ne(arg0) is the same as !(o.eq(arg0)).

o.ne(arg0) is the same as !(o.eq(arg0)).
arg0
the object to compare against this object for reference dis-equality.
returns
false if the argument is not a reference to the receiver object; true otherwise.
attributes: final
definition classes: AnyRef
def notify(): Unit

Wakes up a single thread that is waiting on the receiver object's monitor.

Wakes up a single thread that is waiting on the receiver object's monitor.
attributes: final
definition classes: AnyRef
def notifyAll(): Unit

Wakes up all threads that are waiting on the receiver object's monitor.

Wakes up all threads that are waiting on the receiver object's monitor.
attributes: final
definition classes: AnyRef
def orElse[B >: A](alternative: ⇒ Option[B]): Option[B]

If the option is nonempty return it, otherwise return the result of evaluating an alternative expression.

If the option is nonempty return it, otherwise return the result of evaluating an alternative expression.
alternative
the alternative expression.
definition classes: Option
def orNull[A1 >: A](implicit ev: <:<[Null, A1]): A1

The option's value if it is nonempty, or null if it is empty.

The option's value if it is nonempty, or null if it is empty. The use of null of course is discouraged, but code written to use Options often must interface with code which expects and returns nulls.
definition classes: Option
def productArity: Int

return k for a product A(x_1,.
return k for a product A(x_1,...,x_k) definition classes: None → Product
def productElement(arg0: Int): Any For a product A(x_1,. For a product A(x_1,...,x_k), returns x_(n+1) for 0 <= n < k returns The element n elements after the first element definition classes: None → Product
def productElements: Iterator[Any] definition classes: Product deprecated: use productIterator instead
def productIterator: Iterator[Any] An iterator that returns all fields of this product An iterator that returns all fields of this product definition classes: Product
def productPrefix: String By default the empty 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. definition classes: None → Product
def readResolve(): AnyRef attributes: protected
def synchronized[T0](arg0: T0): T0 attributes: final definition classes: AnyRef
def toLeft[X](right: ⇒ X): Product with Either[A, X] An Either that is a Right with the given argumentright if this is empty, or a Left if this is nonempty with the option's value. An Either that is a Right with the given argumentright if this is empty, or a Left if this is nonempty with the option's value. definition classes: Option
def toList: List[A] A singleton list containing the option's value if it is nonempty or the empty list if the option is empty. A singleton list containing the option's value if it is nonempty or the empty list if the option is empty. definition classes: Option
def toRight[X](left: ⇒ X): Product with Either[X, A] An Either that is a Left with the given argumentleft if this is empty, or a Right if this is nonempty with the option's value. An Either that is a Left with the given argumentleft if this is empty, or a Right if this is nonempty with the option's value. definition classes: Option
def toString(): String Returns a string representation of the object. Returns a string representation of the object. The default representation is platform dependent. returns a string representation of the object. attributes: final definition classes: None → AnyRef → Any
def wait(): Unit attributes: final definition classes: AnyRef
def wait(arg0: Long, arg1: Int): Unit attributes: final definition classes: AnyRef
def wait(arg0: Long): Unit attributes: final definition classes: AnyRef
def withFilter(p: (A) ⇒ Boolean): WithFilter Necessary to keep Option from being implicitly converted to Iterable in for comprehensions. Necessary to keep Option from being implicitly converted to Iterable in for comprehensions. definition classes: Option

None

object None extends Option[Nothing] with Product

Type Members

class WithFilter extends AnyRef

Value Members

def !=(arg0: AnyRef): Boolean

def !=(arg0: Any): Boolean

def ##(): Int

def $asInstanceOf[T0](): T0

def $isInstanceOf[T0](): Boolean

def ==(arg0: AnyRef): Boolean

def ==(arg0: Any): Boolean

def asInstanceOf[T0]: T0

def canEqual(arg0: Any): Boolean

def clone(): AnyRef

def collect[B](pf: PartialFunction[A, B]): Option[B]

def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def exists(p: (A) ⇒ Boolean): Boolean

def filter(p: (A) ⇒ Boolean): Option[A]

def finalize(): Unit

def flatMap[B](f: (A) ⇒ Option[B]): Option[B]

def foreach[U](f: (A) ⇒ U): Unit

def get: Nothing

def getClass(): java.lang.Class[_ <: java.lang.Object]

def getOrElse[B >: A](default: ⇒ B): B

def hashCode(): Int

def isDefined: Boolean

def isEmpty: Boolean

def isInstanceOf[T0]: Boolean

def iterator: Iterator[A]

def map[B](f: (A) ⇒ B): Option[B]

def ne(arg0: AnyRef): Boolean

def notify(): Unit

def notifyAll(): Unit

def orElse[B >: A](alternative: ⇒ Option[B]): Option[B]

def orNull[A1 >: A](implicit ev: <:<[Null, A1]): A1

def productArity: Int

def productElement(arg0: Int): Any

def productElements: Iterator[Any]

def productIterator: Iterator[Any]

def productPrefix: String

def readResolve(): AnyRef

def synchronized[T0](arg0: T0): T0

def toLeft[X](right: ⇒ X): Product with Either[A, X]

def toList: List[A]

def toRight[X](left: ⇒ X): Product with Either[X, A]

def toString(): String

def wait(): Unit

def wait(arg0: Long, arg1: Int): Unit

def wait(arg0: Long): Unit

def withFilter(p: (A) ⇒ Boolean): WithFilter