LeftProjection
Related Doc:
package Either
Test two objects for inequality.
Test two objects for inequality.
true if !(this == that), false otherwise.
Equivalent to x.hashCode except for boxed numeric types and null.
Equivalent to x.hashCode except for boxed numeric types and null.
For numerics, it returns a hash value which is consistent
with value equality: if two value type instances compare
as true, then ## will produce the same hash value for each
of them.
For null returns a hashcode where null.hashCode throws a
NullPointerException.
a hash value consistent with ==
The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).
The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).
true if the receiver object is equivalent to the argument; false otherwise.
Cast the receiver object to be of type T0.
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 expression 1.asInstanceOf[String] will throw a ClassCastException at
runtime, while the expression List(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 type.
the receiver object.
ClassCastException if the receiver object is not an instance of the erasure of type T0.
Create a copy of the receiver object.
Tests whether the argument (that) is a reference to the receiver object (this).
Tests whether the argument (that) is a reference to the receiver object (this).
The eq method implements an equivalence relation on
non-null instances of AnyRef, and has three additional properties:
x and y of type AnyRef, multiple invocations of
x.eq(y) consistently returns true or consistently returns false.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).
true if the argument is a reference to the receiver object; false otherwise.
Returns false if Right or returns the result of the application of
the given function to the Left value.
Returns false if Right or returns the result of the application of
the given function to the Left value.
Left(12).left.exists(_ > 10) // true Left(7).left.exists(_ > 10) // false Right(12).left.exists(_ > 10) // false
Returns None if this is a Right or if the given predicate
p does not hold for the left value, otherwise, returns a Left.
Returns None if this is a Right or if the given predicate
p does not hold for the left value, otherwise, returns a Left.
Left(12).left.filter(_ > 10) // Some(Left(12)) Left(7).left.filter(_ > 10) // None Right(12).left.filter(_ > 10) // None
Called by the garbage collector on the receiver object when there are no more references to the object.
Called by the garbage collector on the receiver object when there are no more references to the object.
The details of when and if the finalize method is invoked, as
well as the interaction between finalize and non-local returns
and exceptions, are all platform dependent.
Binds the given function across Left.
Binds the given function across Left.
Left(12).left.flatMap(x => Left("scala")) // Left("scala") Right(12).left.flatMap(x => Left("scala") // Right(12)
The function to bind across Left.
Returns true if Right or returns the result of the application of
the given function to the Left value.
Returns true if Right or returns the result of the application of
the given function to the Left value.
Left(12).left.forall(_ > 10) // true Left(7).left.forall(_ > 10) // false Right(12).left.forall(_ > 10) // true
Executes the given side-effecting function if this is a Left.
Executes the given side-effecting function if this is a Left.
Left(12).left.foreach(x => println(x)) // prints "12" Right(12).left.foreach(x => println(x)) // doesn't print
The side-effecting function to execute.
Returns string formatted according to given format string.
Returns string formatted according to given format string.
Format strings are as for String.format
(@see java.lang.String.format).
Returns the value from this Left or throws java.util.NoSuchElementException
if this is a Right.
Returns the value from this Left or throws java.util.NoSuchElementException
if this is a Right.
Left(12).left.get // 12 Right(12).left.get // NoSuchElementException
java.util.NoSuchElementException if the projection is scala.util.Right
A representation that corresponds to the dynamic class of the receiver object.
A representation that corresponds to the dynamic class of the receiver object.
The nature of the representation is platform dependent.
a representation that corresponds to the dynamic class of the receiver object.
not specified by SLS as a member of AnyRef
Returns the value from this Left or the given argument if this is a
Right.
Returns the value from this Left or the given argument if this is a
Right.
Left(12).left.getOrElse(17) // 12 Right(12).left.getOrElse(17) // 17
Test whether the dynamic type of the receiver object is T0.
Test whether the dynamic type of the receiver object is T0.
Note that the result of the test is modulo Scala's erasure semantics.
Therefore the expression 1.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 specified type.
true if the receiver object is an instance of erasure of type T0; false otherwise.
Maps the function argument through Left.
Maps the function argument through Left.
Left(12).left.map(_ + 2) // Left(14) Right[Int, Int](12).left.map(_ + 2) // Right(12)
Equivalent to !(this eq that).
Equivalent to !(this eq that).
true if the argument is not a reference to the receiver object; false otherwise.
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.
not specified by SLS as a member of AnyRef
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.
not specified by SLS as a member of AnyRef
Returns a Some containing the Left value if it exists or a
None if this is a Right.
Returns a Some containing the Left value if it exists or a
None if this is a Right.
Left(12).left.toOption // Some(12) Right(12).left.toOption // None
Returns a Seq containing the Left value if it exists or an empty
Seq if this is a Right.
Returns a Seq containing the Left value if it exists or an empty
Seq if this is a Right.
Left(12).left.toSeq // Seq(12) Right(12).left.toSeq // Seq()
Projects an
Eitherinto aLeft.This allows for-comprehensions over Either instances - for example
Continuing the analogy with scala.Option, a
LeftProjectiondeclares thatLeftshould be analogous toSomein some code.1.0, 11/10/2008