Scala Library
scala.Either

class LeftProjection
[source: scala/Either.scala]
case final class LeftProjection[+A, +B](val e : Either[A, B])
extends Product
Projects an Either into a Left.
Author
Tony Morris, Workingmouse
Version
1.0, 11/10/2008
Method Summary
override 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. See Programming in Scala, Chapter 28 for discussion and design.
override def equals (arg0 : Any) : Boolean
The equality method defined in `AnyRef`.
def exists (f : (A) => Boolean) : Boolean
Returns false if Right or returns the result of the application of the given function to the Left value.
def filter [Y](p : (A) => Boolean) : Option[Either[A, Y]]
Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.
def flatMap [BB >: B, X](f : (A) => Either[X, BB]) : Either[X, BB]
Binds the given function across Left.
def forall (f : (A) => Boolean) : Boolean
Returns true if Right or returns the result of the application of the given function to the Left value.
def foreach [U](f : (A) => U) : Any
Executes the given side-effect if this is a Left.
def get : A
Returns the value from this Left or throws Predef.NoSuchElementException if this is a Right.
def getOrElse [AA >: A](or : => AA) : AA
Returns the value from this Left or the given argument if this is a Right.
override def hashCode : Int
Returns a hash code value for the object.
def map [X](f : (A) => X) : Product with Either[X, B]
Maps the function argument through Left.
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.
def toOption : Option[A]
Returns a Some containing the Left value if it exists or a None if this is a Right.
def toSeq : Seq[A]
Returns a Seq containing the Left value if it exists or an empty Seq if this is a Right.
override def toString : java.lang.String
Returns a string representation of the object.
Methods inherited from Product
productIterator, productElements
Methods inherited from AnyRef
getClass, clone, notify, notifyAll, wait, wait, wait, finalize, ==, !=, eq, ne, synchronized
Methods inherited from Any
==, !=, isInstanceOf, asInstanceOf
Method Details
def get : A
Returns the value from this Left or throws Predef.NoSuchElementException if this is a Right.
Throws
Predef.NoSuchElementException - if the option is empty.
def foreach[U](f : (A) => U) : Any
Executes the given side-effect if this is a Left.
Parameters
e - The side-effect to execute.
def getOrElse[AA >: A](or : => AA) : AA
Returns the value from this Left or the given argument if this is a Right.
def forall(f : (A) => Boolean) : Boolean
Returns true if Right or returns the result of the application of the given function to the Left value.
def exists(f : (A) => Boolean) : Boolean
Returns false if Right or returns the result of the application of the given function to the Left value.
def flatMap[BB >: B, X](f : (A) => Either[X, BB]) : Either[X, BB]
Binds the given function across Left.
Parameters
The - function to bind across Left.
def map[X](f : (A) => X) : Product with Either[X, B]
Maps the function argument through Left.
def filter[Y](p : (A) => Boolean) : Option[Either[A, Y]]
Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.
def toSeq : Seq[A]
Returns a Seq containing the Left value if it exists or an empty Seq if this is a Right.
def toOption : Option[A]
Returns a Some containing the Left value if it exists or a None if this is a Right.
override def hashCode : Int
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.

override def toString : java.lang.String
Returns a string representation of the object.

The default representation is platform dependent.

Returns
a string representation of the object.

override def equals(arg0 : Any) : Boolean
The equality method defined in `AnyRef`.
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.
Overrides
Product.productPrefix
override def productArity : Int
return k for a product A(x_1,...,x_k)
Overrides
Product.productArity
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
Overrides
Product.productElement
override 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. See Programming in Scala, Chapter 28 for discussion and design.
Scala Library