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.
Equivalent to x.hashCode
except for boxed numeric types.
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.
a hash value consistent with ==
Test two objects for equality.
Test two objects for equality.
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.
if the receiver object is not an instance of the erasure of type T0
.
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.
true if this instance can possibly equal that
, otherwise false
Create a copy of the receiver object.
Tests whether the argument (arg0
) is a reference to the receiver object (this
).
Tests whether the argument (arg0
) 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.
The universal equality method defined in AnyRef
.
The universal equality method defined in AnyRef
.
true
if the receiver object is equivalent to the argument; 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)
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
Returns the value from this Left
or throws Predef.NoSuchElementException
if this is a Right
.
Returns the value from this Left
or throws Predef.NoSuchElementException
if this is a Right
.
Left(12).left.get // 12 Right(12).left.get // NoSuchElementException
if the projection is 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
The hashCode method for reference types.
The hashCode method for reference types. See hashCode in Any.
the hash code value for this object.
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
The size of this product.
The size of this product.
for a product A(x_1, ..., x_k)
, returns k
The nth element of this product, 0-based.
The nth element of this product, 0-based. In other words, for a
product A(x_1, ..., x_k)
, returns x_(n+1) where 0 < n < k.
the element n
elements after the first element
An iterator over all the elements of this product.
An iterator over all the elements of this product.
in the default implementation, an Iterator[Any]
A string used in the toString
methods of derived classes.
A string used in the toString
methods of derived classes.
Implementations may override this method to prepend a string prefix
to the result of toString methods.
in the default implementation, the empty string
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()
Creates a String representation of this object.
Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.
a String representation of the object.
(Since version 2.8.0) use productIterator instead
Projects an
Either
into aLeft
.This allows for-comprehensions over Either instances - for example
Continuing the analogy with Option, a
LeftProjection
declares thatLeft
should be analogous toSome
in some code.1.0, 11/10/2008