Scala Standard Library2.12.2 < Back
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# Packages

-  package root

  This is the documentation for the Scala standard library.

  This is the documentation for the Scala standard library.

  #### Package structure

  The scala package contains core types like `Int`, `Float`, `Array` or `Option` which are accessible in all Scala compilation units without explicit qualification or imports.

  Notable packages include:

  - `scala.collection` and its sub-packages contain Scala's collections framework
    - `scala.collection.immutable` - Immutable, sequential data-structures such as `Vector`, `List`, `Range`, `HashMap` or `HashSet`
    - `scala.collection.mutable` - Mutable, sequential data-structures such as `ArrayBuffer`, `StringBuilder`, `HashMap` or `HashSet`
    - `scala.collection.concurrent` - Mutable, concurrent data-structures such as `TrieMap`
    - `scala.collection.parallel.immutable` - Immutable, parallel data-structures such as `ParVector`, `ParRange`, `ParHashMap` or `ParHashSet`
    - `scala.collection.parallel.mutable` - Mutable, parallel data-structures such as `ParArray`, `ParHashMap`, `ParTrieMap` or `ParHashSet`
  - `scala.concurrent` - Primitives for concurrent programming such as `Futures` and `Promises`
  - `scala.io` - Input and output operations
  - `scala.math` - Basic math functions and additional numeric types like `BigInt` and `BigDecimal`
  - `scala.sys` - Interaction with other processes and the operating system
  - `scala.util.matching` - Regular expressions

  Other packages exist. See the complete list on the right.

  Additional parts of the standard library are shipped as separate libraries. These include:

  - `scala.reflect` - Scala's reflection API (scala-reflect.jar)
  - `scala.xml` - XML parsing, manipulation, and serialization (scala-xml.jar)
  - `scala.swing` - A convenient wrapper around Java's GUI framework called Swing (scala-swing.jar)
  - `scala.util.parsing` - Parser combinators (scala-parser-combinators.jar)

  #### Automatic imports

  Identifiers in the scala package and the `scala.Predef` object are always in scope by default.

  Some of these identifiers are type aliases provided as shortcuts to commonly used classes. For example, `List` is an alias for `scala.collection.immutable.List`.

  Other aliases refer to classes provided by the underlying platform. For example, on the JVM, `String` is an alias for `java.lang.String`.

  Definition Classes
    root
-  package scala

  Core Scala types.

  Core Scala types. They are always available without an explicit import.

  Definition Classes
    root
-  package annotation
  Definition Classes
    scala
-  package beans
  Definition Classes
    scala
-  package collection

  Contains the base traits and objects needed to use and extend Scala's collection library.

  Contains the base traits and objects needed to use and extend Scala's collection library.

  #### Guide

  A detailed guide for using the collections library is available at http://docs.scala-lang.org/overviews/collections/introduction.html. Developers looking to extend the collections library can find a description of its architecture at http://docs.scala-lang.org/overviews/core/architecture-of-scala-collections.html.

  #### Using Collections

  It is convenient to treat all collections as either a scala.collection.Traversable or scala.collection.Iterable, as these traits define the vast majority of operations on a collection.

  Collections can, of course, be treated as specifically as needed, and the library is designed to ensure that the methods that transform collections will return a collection of the same type:

      scala> val array = Array(1,2,3,4,5,6)
      array: Array[Int] = Array(1, 2, 3, 4, 5, 6)

      scala> array map { _.toString }
      res0: Array[String] = Array(1, 2, 3, 4, 5, 6)

      scala> val list = List(1,2,3,4,5,6)
      list: List[Int] = List(1, 2, 3, 4, 5, 6)

      scala> list map { _.toString }
      res1: List[String] = List(1, 2, 3, 4, 5, 6)

  #### Creating Collections

  The most common way to create a collection is to use its companion object as a factory. The three most commonly used collections are scala.collection.Seq, scala.collection.immutable.Set, and scala.collection.immutable.Map. They can be used directly as shown below since their companion objects are all available as type aliases in either the scala package or in `scala.Predef`. New collections are created like this:

      scala> val seq = Seq(1,2,3,4,1)
      seq: Seq[Int] = List(1, 2, 3, 4, 1)

      scala> val set = Set(1,2,3,4,1)
      set: scala.collection.immutable.Set[Int] = Set(1, 2, 3, 4)

      scala> val map = Map(1 -> "one", 2 -> "two", 3 -> "three", 2 -> "too")
      map: scala.collection.immutable.Map[Int,String] = Map(1 -> one, 2 -> too, 3 -> three)

  It is also typical to prefer the scala.collection.immutable collections over those in scala.collection.mutable; the types aliased in the `scala.Predef` object are the immutable versions.

  Also note that the collections library was carefully designed to include several implementations of each of the three basic collection types. These implementations have specific performance characteristics which are described in the guide.

  The concrete parallel collections also have specific performance characteristics which are described in the parallel collections guide

  ##### Converting to and from Java Collections

  The scala.collection.JavaConverters object provides a collection of decorators that allow converting between Scala and Java collections using `asScala` and `asJava` methods.

  Definition Classes
    scala
-  package compat
  Definition Classes
    scala
-  package concurrent

  This package object contains primitives for concurrent and parallel programming.

  This package object contains primitives for concurrent and parallel programming.

  #### Guide

  A more detailed guide to Futures and Promises, including discussion and examples can be found at http://docs.scala-lang.org/overviews/core/futures.html.

  #### Common Imports

  When working with Futures, you will often find that importing the whole concurrent package is convenient:

      import scala.concurrent._

  When using things like `Future`s, it is often required to have an implicit `ExecutionContext` in scope. The general advice for these implicits are as follows.

  If the code in question is a class or method definition, and no `ExecutionContext` is available, request one from the caller by adding an implicit parameter list:

      def myMethod(myParam: MyType)(implicit ec: ExecutionContext) = …
      //Or
      class MyClass(myParam: MyType)(implicit ec: ExecutionContext) { … }

  This allows the caller of the method, or creator of the instance of the class, to decide which `ExecutionContext` should be used.

  For typical REPL usage and experimentation, importing the global `ExecutionContext` is often desired.

      import scala.concurrent.ExcutionContext.Implicits.global

  #### Specifying Durations

  Operations often require a duration to be specified. A duration DSL is available to make defining these easier:

      import scala.concurrent.duration._
      val d: Duration = 10.seconds

  #### Using Futures For Non-blocking Computation

  Basic use of futures is easy with the factory method on Future, which executes a provided function asynchronously, handing you back a future result of that function without blocking the current thread. In order to create the Future you will need either an implicit or explicit ExecutionContext to be provided:

      import scala.concurrent._
      import ExecutionContext.Implicits.global  // implicit execution context

      val firstZebra: Future[Int] = Future {
        val source = scala.io.Source.fromFile("/etc/dictionaries-common/words")
        source.toSeq.indexOfSlice("zebra")
      }

  #### Avoid Blocking

  Although blocking is possible in order to await results (with a mandatory timeout duration):

      import scala.concurrent.duration._
      Await.result(firstZebra, 10.seconds)

  and although this is sometimes necessary to do, in particular for testing purposes, blocking in general is discouraged when working with Futures and concurrency in order to avoid potential deadlocks and improve performance. Instead, use callbacks or combinators to remain in the future domain:

      val animalRange: Future[Int] = for {
        aardvark <- firstAardvark
        zebra <- firstZebra
      } yield zebra - aardvark

      animalRange.onSuccess {
        case x if x > 500000 => println("It's a long way from Aardvark to Zebra")
      }

  Definition Classes
    scala
-  package io
  Definition Classes
    scala
-  package math

  The package object `scala.math` contains methods for performing basic numeric operations such as elementary exponential, logarithmic, root and trigonometric functions.

  The package object `scala.math` contains methods for performing basic numeric operations such as elementary exponential, logarithmic, root and trigonometric functions.

  All methods forward to java.lang.Math unless otherwise noted.

  Definition Classes
    scala
  See also

    java.lang.Math

-  package ref
  Definition Classes
    scala
-  package reflect
  Definition Classes
    scala
-  package runtime
  Definition Classes
    scala
-  package sys

  The package object `scala.sys` contains methods for reading and altering core aspects of the virtual machine as well as the world outside of it.

  The package object `scala.sys` contains methods for reading and altering core aspects of the virtual machine as well as the world outside of it.

  Definition Classes
    scala
  Version

    2.9

  Since

    2.9

-  package text
  Definition Classes
    scala
-  package util
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o

scala

# Predef 

###

#### object Predef extends LowPriorityImplicits with DeprecatedPredef

The `Predef` object provides definitions that are accessible in all Scala compilation units without explicit qualification.

##### Commonly Used Types

Predef provides type aliases for types which are commonly used, such as the immutable collection types scala.collection.immutable.Map, scala.collection.immutable.Set, and the scala.collection.immutable.List constructors (scala.collection.immutable.:: and scala.collection.immutable.Nil).

##### Console Output

For basic console output, `Predef` provides convenience methods print and println, which are aliases of the methods in the object scala.Console.

##### Assertions

A set of `assert` functions are provided for use as a way to document and dynamically check invariants in code. Invocations of `assert` can be elided at compile time by providing the command line option `-Xdisable-assertions`, which raises `-Xelide-below` above `elidable.ASSERTION`, to the `scalac` command.

Variants of `assert` intended for use with static analysis tools are also provided: `assume`, `require` and `ensuring`. `require` and `ensuring` are intended for use as a means of design-by-contract style specification of pre- and post-conditions on functions, with the intention that these specifications could be consumed by a static analysis tool. For instance,

    def addNaturals(nats: List[Int]): Int = {
      require(nats forall (_ >= 0), "List contains negative numbers")
      nats.foldLeft(0)(_ + _)
    } ensuring(_ >= 0)

The declaration of `addNaturals` states that the list of integers passed should only contain natural numbers (i.e. non-negative), and that the result returned will also be natural. `require` is distinct from `assert` in that if the condition fails, then the caller of the function is to blame rather than a logical error having been made within `addNaturals` itself. `ensuring` is a form of `assert` that declares the guarantee the function is providing with regards to its return value.

##### Implicit Conversions

A number of commonly applied implicit conversions are also defined here, and in the parent type scala.LowPriorityImplicits. Implicit conversions are provided for the "widening" of numeric values, for instance, converting a Short value to a Long value as required, and to add additional higher-order functions to Array values. These are described in more detail in the documentation of scala.Array.

Source
  Predef.scala

Linear Supertypes
DeprecatedPredef, LowPriorityImplicits, AnyRef, Any
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Ordering

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Inherited

1. Predef
2. DeprecatedPredef
3. LowPriorityImplicits
4. AnyRef
5. Any

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Visibility

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### Type Members

1.  sealed abstract class <:< [-From, +To] extends (From) ⇒ To with Serializable

   An instance of `A <:< B` witnesses that `A` is a subtype of `B`.

   An instance of `A <:< B` witnesses that `A` is a subtype of `B`. Requiring an implicit argument of the type `A <:< B` encodes the generalized constraint `A <: B`.

   Annotations
     @implicitNotFound( msg = ... )
   Note

     we need a new type constructor `<:<` and evidence `conforms`, as reusing `Function1` and `identity` leads to ambiguities in case of type errors (`any2stringadd` is inferred) To constrain any abstract type T that's in scope in a method's argument list (not just the method's own type parameters) simply add an implicit argument of type `T <:< U`, where `U` is the required upper bound; or for lower-bounds, use: `L <:< T`, where `L` is the required lower bound. In part contributed by Jason Zaugg.

2.  sealed abstract class =:= [From, To] extends (From) ⇒ To with Serializable

   An instance of `A =:= B` witnesses that the types `A` and `B` are equal.

   An instance of `A =:= B` witnesses that the types `A` and `B` are equal.

   Annotations
     @implicitNotFound( msg = ... )
   See also

     `<:<` for expressing subtyping constraints

3.  implicit final class ArrayCharSequence extends CharSequence

4.  implicit final class ArrowAssoc [A] extends AnyVal

5.  type Class[T] = java.lang.Class[T]

6.  class DummyImplicit extends AnyRef

   A type for which there is always an implicit value.

   A type for which there is always an implicit value.

   See also

     scala.Array$, method `fallbackCanBuildFrom`

7.  implicit final class Ensuring [A] extends AnyVal

8.  type Function[-A, +B] = (A) ⇒ B

9.  type Manifest[T] = reflect.Manifest[T]
   Annotations
     @implicitNotFound( msg = "No Manifest available for ${T}." )
10.  type Map[A, +B] = collection.immutable.Map[A, B]

11.  type OptManifest[T] = reflect.OptManifest[T]
12.  implicit final class RichException extends AnyVal
13.  implicit final class SeqCharSequence extends CharSequence

14.  type Set[A] = collection.immutable.Set[A]

15.  type String = java.lang.String

    The `String` type in Scala has methods that come either from the underlying Java String (see the documentation corresponding to your Java version, for example http://docs.oracle.com/javase/8/docs/api/java/lang/String.html) or are added implicitly through scala.collection.immutable.StringOps.

16.  implicit final class StringFormat [A] extends AnyVal

17.  implicit final class any2stringadd [A] extends AnyVal

18.  type ClassManifest[T] = ClassTag[T]
    Annotations
      @implicitNotFound( msg = ... ) @deprecated
    Deprecated

      (Since version 2.10.0) use `scala.reflect.ClassTag` instead

19.  type Pair[+A, +B] = (A, B)
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use built-in tuple syntax or Tuple2 instead

20.  type Triple[+A, +B, +C] = (A, B, C)
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use built-in tuple syntax or Tuple3 instead

### Value Members

1.  final def !=(arg0: Any): Boolean

   Test two objects for inequality.

   Test two objects for inequality.

   returns

     `true` if !(this == that), false otherwise.

   Definition Classes
     AnyRef → Any
2.  final def ##(): Int

   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`.

   returns

     a hash value consistent with ==

   Definition Classes
     AnyRef → Any
3.  implicit def $conforms[A]: <:<[A, A]

4.  final def ==(arg0: Any): Boolean

   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)`.

   returns

     `true` if the receiver object is equivalent to the argument; `false` otherwise.

   Definition Classes
     AnyRef → Any
5.  def ???: Nothing

   `???` can be used for marking methods that remain to be implemented.

   `???` can be used for marking methods that remain to be implemented.

   Exceptions thrown
6.  implicit def Boolean2boolean(x: java.lang.Boolean): Boolean

7.  implicit def Byte2byte(x: java.lang.Byte): Byte

8.  implicit def Character2char(x: Character): Char

9.  implicit def Double2double(x: java.lang.Double): Double

10.  implicit def Float2float(x: java.lang.Float): Float

11.  implicit def Integer2int(x: Integer): Int

12.  implicit def Long2long(x: java.lang.Long): Long

13.  val Manifest: ManifestFactory.type
14.  val Map: collection.immutable.Map.type

15.  val NoManifest: reflect.NoManifest.type
16.  val Set: collection.immutable.Set.type

17.  implicit def Short2short(x: java.lang.Short): Short

18.  implicit val StringCanBuildFrom: CanBuildFrom[String, Char, String]
19.  final def asInstanceOf[T0]: T0

    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.

    returns

      the receiver object.

    Definition Classes
      Any
    Exceptions thrown

      `ClassCastException` if the receiver object is not an instance of the erasure of type `T0`.

20.  final def assert(assertion: Boolean, message: ⇒ Any): Unit

    Tests an expression, throwing an `AssertionError` if false.

    Tests an expression, throwing an `AssertionError` if false. Calls to this method will not be generated if `-Xelide-below` is greater than `ASSERTION`.

    assertion

      the expression to test

    message

      a String to include in the failure message

    Annotations
      @elidable( level = ASSERTION ) @inline()
    See also

      elidable

21.  def assert(assertion: Boolean): Unit

    Tests an expression, throwing an `AssertionError` if false.

    Tests an expression, throwing an `AssertionError` if false. Calls to this method will not be generated if `-Xelide-below` is greater than `ASSERTION`.

    assertion

      the expression to test

    Annotations
      @elidable( level = ASSERTION )
    See also

      elidable

22.  final def assume(assumption: Boolean, message: ⇒ Any): Unit

    Tests an expression, throwing an `AssertionError` if false.

    Tests an expression, throwing an `AssertionError` if false. This method differs from assert only in the intent expressed: assert contains a predicate which needs to be proven, while assume contains an axiom for a static checker. Calls to this method will not be generated if `-Xelide-below` is greater than `ASSERTION`.

    assumption

      the expression to test

    message

      a String to include in the failure message

    Annotations
      @elidable( level = ASSERTION ) @inline()
    See also

      elidable

23.  def assume(assumption: Boolean): Unit

    Tests an expression, throwing an `AssertionError` if false.

    Tests an expression, throwing an `AssertionError` if false. This method differs from assert only in the intent expressed: assert contains a predicate which needs to be proven, while assume contains an axiom for a static checker. Calls to this method will not be generated if `-Xelide-below` is greater than `ASSERTION`.

    assumption

      the expression to test

    Annotations
      @elidable( level = ASSERTION )
    See also

      elidable

24.  implicit def augmentString(x: String): StringOps

    Annotations
      @inline()
25.  implicit def boolean2Boolean(x: Boolean): java.lang.Boolean

26.  implicit def booleanArrayOps(xs: Array[Boolean]): ofBoolean
27.  implicit def booleanWrapper(x: Boolean): RichBoolean
    Definition Classes
      LowPriorityImplicits
    Annotations
      @inline()
28.  implicit def byte2Byte(x: Byte): java.lang.Byte

29.  implicit def byteArrayOps(xs: Array[Byte]): ofByte
30.  implicit def byteWrapper(x: Byte): RichByte

    We prefer the java.lang.* boxed types to these wrappers in any potential conflicts.

    We prefer the java.lang.* boxed types to these wrappers in any potential conflicts. Conflicts do exist because the wrappers need to implement ScalaNumber in order to have a symmetric equals method, but that implies implementing java.lang.Number as well.

    Note - these are inlined because they are value classes, but the call to xxxWrapper is not eliminated even though it does nothing. Even inlined, every call site does a no-op retrieval of Predef's MODULE$ because maybe loading Predef has side effects!

    Definition Classes
      LowPriorityImplicits
    Annotations
      @inline()
31.  implicit def char2Character(x: Char): Character

32.  implicit def charArrayOps(xs: Array[Char]): ofChar
33.  implicit def charWrapper(c: Char): RichChar
    Definition Classes
      LowPriorityImplicits
    Annotations
      @inline()
34.  def classOf[T]: Class[T]

    Retrieve the runtime representation of a class type.

    Retrieve the runtime representation of a class type. `classOf[T]` is equivalent to the class literal `T.class` in Java.

    Example:

    1.     val listClass = classOf[List[_]]
           // listClass is java.lang.Class[List[_]] = class scala.collection.immutable.List

           val mapIntString = classOf[Map[Int,String]]
           // mapIntString is java.lang.Class[Map[Int,String]] = interface scala.collection.immutable.Map

35.  def clone(): AnyRef

    Create a copy of the receiver object.

    Create 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[java.lang]
    Definition Classes
      AnyRef
    Annotations
      @throws( ... )
    Note

      not specified by SLS as a member of AnyRef

36.  implicit def double2Double(x: Double): java.lang.Double

37.  implicit def doubleArrayOps(xs: Array[Double]): ofDouble
38.  implicit def doubleWrapper(x: Double): RichDouble
    Definition Classes
      LowPriorityImplicits
    Annotations
      @inline()
39.  final def eq(arg0: AnyRef): Boolean

    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:

    - 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`).

    returns

      `true` if the argument is a reference to the receiver object; `false` otherwise.

    Definition Classes
      AnyRef
40.  def equals(arg0: Any): Boolean

    The equality method for reference types.

    The equality method for reference types. Default implementation delegates to `eq`.

    See also `equals` in scala.Any.

    returns

      `true` if the receiver object is equivalent to the argument; `false` otherwise.

    Definition Classes
      AnyRef → Any
41.  implicit def fallbackStringCanBuildFrom[T]: CanBuildFrom[String, T, collection.immutable.IndexedSeq[T]]
    Definition Classes
      LowPriorityImplicits
42.  def finalize(): Unit

    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.

    Attributes
      protected[java.lang]
    Definition Classes
      AnyRef
    Annotations
      @throws( classOf[java.lang.Throwable] )
    Note

      not specified by SLS as a member of AnyRef

43.  implicit def float2Float(x: Float): java.lang.Float

44.  implicit def floatArrayOps(xs: Array[Float]): ofFloat
45.  implicit def floatWrapper(x: Float): RichFloat
    Definition Classes
      LowPriorityImplicits
    Annotations
      @inline()
46.  implicit def genericArrayOps[T](xs: Array[T]): ArrayOps[T]
47.  implicit def genericWrapArray[T](xs: Array[T]): WrappedArray[T]

    Definition Classes
      LowPriorityImplicits
48.  final def getClass(): java.lang.Class[_]

    Returns the runtime class representation of the object.

    Returns the runtime class representation of the object.

    returns

      a class object corresponding to the runtime type of the receiver.

    Definition Classes
      AnyRef → Any
49.  def hashCode(): Int

    The hashCode method for reference types.

    The hashCode method for reference types. See hashCode in scala.Any.

    returns

      the hash code value for this object.

    Definition Classes
      AnyRef → Any
50.  def identity[A](x: A): A

    Annotations
      @inline()
51.  def implicitly[T](implicit e: T): T

    Annotations
      @inline()
52.  implicit def int2Integer(x: Int): Integer

53.  implicit def intArrayOps(xs: Array[Int]): ofInt
54.  implicit def intWrapper(x: Int): RichInt
    Definition Classes
      LowPriorityImplicits
    Annotations
      @inline()
55.  final def isInstanceOf[T0]: Boolean

    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.

    returns

      `true` if the receiver object is an instance of erasure of type `T0`; `false` otherwise.

    Definition Classes
      Any
56.  def locally[T](x: T): T

    Annotations
      @inline()
57.  implicit def long2Long(x: Long): java.lang.Long

58.  implicit def longArrayOps(xs: Array[Long]): ofLong
59.  implicit def longWrapper(x: Long): RichLong
    Definition Classes
      LowPriorityImplicits
    Annotations
      @inline()
60.  def manifest[T](implicit m: Manifest[T]): Manifest[T]
61.  final def ne(arg0: AnyRef): Boolean

    Equivalent to `!(this eq that)`.

    Equivalent to `!(this eq that)`.

    returns

      `true` if the argument is not a reference to the receiver object; `false` otherwise.

    Definition Classes
      AnyRef
62.  final 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.

    Definition Classes
      AnyRef
    Note

      not specified by SLS as a member of AnyRef

63.  final 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.

    Definition Classes
      AnyRef
    Note

      not specified by SLS as a member of AnyRef

64.  def optManifest[T](implicit m: OptManifest[T]): OptManifest[T]
65.  def print(x: Any): Unit

    Prints an object to `out` using its `toString` method.

    Prints an object to `out` using its `toString` method.

    x

      the object to print; may be null.

66.  def printf(text: String, xs: Any*): Unit

    Prints its arguments as a formatted string to the default output, based on a string pattern (in a fashion similar to printf in C).

    Prints its arguments as a formatted string to the default output, based on a string pattern (in a fashion similar to printf in C).

    The interpretation of the formatting patterns is described in java.util.Formatter.

    Consider using the f interpolator as more type safe and idiomatic.

    text

      the pattern for formatting the arguments.

    Exceptions thrown

      `java.lang.IllegalArgumentException` if there was a problem with the format string or arguments

    See also

      StringContext.f

67.  def println(x: Any): Unit

    Prints out an object to the default output, followed by a newline character.

    Prints out an object to the default output, followed by a newline character.

    x

      the object to print.

68.  def println(): Unit

    Prints a newline character on the default output.

69.  implicit def refArrayOps[T <: AnyRef](xs: Array[T]): ofRef[T]
70.  final def require(requirement: Boolean, message: ⇒ Any): Unit

    Tests an expression, throwing an `IllegalArgumentException` if false.

    Tests an expression, throwing an `IllegalArgumentException` if false. This method is similar to `assert`, but blames the caller of the method for violating the condition.

    requirement

      the expression to test

    message

      a String to include in the failure message

    Annotations
      @inline()
71.  def require(requirement: Boolean): Unit

    Tests an expression, throwing an `IllegalArgumentException` if false.

    Tests an expression, throwing an `IllegalArgumentException` if false. This method is similar to `assert`, but blames the caller of the method for violating the condition.

    requirement

      the expression to test

72.  implicit def short2Short(x: Short): java.lang.Short

73.  implicit def shortArrayOps(xs: Array[Short]): ofShort
74.  implicit def shortWrapper(x: Short): RichShort
    Definition Classes
      LowPriorityImplicits
    Annotations
      @inline()
75.  final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
      AnyRef
76.  def toString(): java.lang.String

    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.

    returns

      a String representation of the object.

    Definition Classes
      AnyRef → Any
77.  implicit def tuple2ToZippedOps[T1, T2](x: (T1, T2)): Ops[T1, T2]
78.  implicit def tuple3ToZippedOps[T1, T2, T3](x: (T1, T2, T3)): Ops[T1, T2, T3]
79.  implicit def unaugmentString(x: StringOps): String

    Annotations
      @inline()
80.  implicit def unitArrayOps(xs: Array[Unit]): ofUnit
81.  implicit def unwrapString(ws: WrappedString): String

    Definition Classes
      LowPriorityImplicits
82.  final def wait(): Unit
    Definition Classes
      AnyRef
    Annotations
      @throws( ... )
83.  final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
      AnyRef
    Annotations
      @throws( ... )
84.  final def wait(arg0: Long): Unit
    Definition Classes
      AnyRef
    Annotations
      @throws( ... )
85.  implicit def wrapBooleanArray(xs: Array[Boolean]): WrappedArray[Boolean]

    Definition Classes
      LowPriorityImplicits
86.  implicit def wrapByteArray(xs: Array[Byte]): WrappedArray[Byte]

    Definition Classes
      LowPriorityImplicits
87.  implicit def wrapCharArray(xs: Array[Char]): WrappedArray[Char]

    Definition Classes
      LowPriorityImplicits
88.  implicit def wrapDoubleArray(xs: Array[Double]): WrappedArray[Double]

    Definition Classes
      LowPriorityImplicits
89.  implicit def wrapFloatArray(xs: Array[Float]): WrappedArray[Float]

    Definition Classes
      LowPriorityImplicits
90.  implicit def wrapIntArray(xs: Array[Int]): WrappedArray[Int]

    Definition Classes
      LowPriorityImplicits
91.  implicit def wrapLongArray(xs: Array[Long]): WrappedArray[Long]

    Definition Classes
      LowPriorityImplicits
92.  implicit def wrapRefArray[T <: AnyRef](xs: Array[T]): WrappedArray[T]

    Definition Classes
      LowPriorityImplicits
93.  implicit def wrapShortArray(xs: Array[Short]): WrappedArray[Short]

    Definition Classes
      LowPriorityImplicits
94.  implicit def wrapString(s: String): WrappedString

    Definition Classes
      LowPriorityImplicits
95.  implicit def wrapUnitArray(xs: Array[Unit]): WrappedArray[Unit]

    Definition Classes
      LowPriorityImplicits
96.  object =:= extends Serializable

97.  object DummyImplicit

### Deprecated Value Members

1.  val ClassManifest: ClassManifestFactory.type
   Annotations
     @deprecated
   Deprecated

     (Since version 2.10.0) use `scala.reflect.ClassTag` instead

2.  def any2ArrowAssoc[A](x: A): ArrowAssoc[A]
   Definition Classes
     DeprecatedPredef
   Annotations
     @deprecated
   Deprecated

     (Since version 2.11.0) use `ArrowAssoc`

3.  def any2Ensuring[A](x: A): Ensuring[A]
   Definition Classes
     DeprecatedPredef
   Annotations
     @deprecated
   Deprecated

     (Since version 2.11.0) use `Ensuring`

4.  def any2stringfmt(x: Any): StringFormat[Any]
   Definition Classes
     DeprecatedPredef
   Annotations
     @deprecated
   Deprecated

     (Since version 2.11.0) use `StringFormat`

5.  def arrayToCharSequence(xs: Array[Char]): CharSequence
   Definition Classes
     DeprecatedPredef
   Annotations
     @deprecated
   Deprecated

     (Since version 2.11.0) use `ArrayCharSequence`

6.  def classManifest[T](implicit m: ClassManifest[T]): ClassManifest[T]
   Annotations
     @deprecated
   Deprecated

     (Since version 2.10.0) use scala.reflect.classTag[T] instead

7.  def conforms[A]: <:<[A, A]
   Annotations
     @deprecated
   Deprecated

     (Since version 2.11.0) use `implicitly[T <:< U]` or `identity` instead.

8.  def exceptionWrapper(exc: scala.Throwable): RichException
   Definition Classes
     DeprecatedPredef
   Annotations
     @deprecated
   Deprecated

     (Since version 2.11.0) use `Throwable` directly

9.  def readBoolean(): Boolean
   Definition Classes
     DeprecatedPredef
   Annotations
     @deprecated
   Deprecated

     (Since version 2.11.0) use the method in `scala.io.StdIn`

10.  def readByte(): Byte
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

11.  def readChar(): Char
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

12.  def readDouble(): Double
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

13.  def readFloat(): Float
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

14.  def readInt(): Int
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

15.  def readLine(text: String, args: Any*): String
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

16.  def readLine(): String
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

17.  def readLong(): Long
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

18.  def readShort(): Short
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

19.  def readf(format: String): List[Any]
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

20.  def readf1(format: String): Any
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

21.  def readf2(format: String): (Any, Any)
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

22.  def readf3(format: String): (Any, Any, Any)
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use the method in `scala.io.StdIn`

23.  def seqToCharSequence(xs: collection.IndexedSeq[Char]): CharSequence
    Definition Classes
      DeprecatedPredef
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use `SeqCharSequence`

24.  object Pair
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use built-in tuple syntax or Tuple2 instead

25.  object Triple
    Annotations
      @deprecated
    Deprecated

      (Since version 2.11.0) use built-in tuple syntax or Tuple3 instead

### Inherited from DeprecatedPredef

### Inherited from LowPriorityImplicits

### Inherited from AnyRef

### Inherited from Any

### Utility Methods

### Assertions

These methods support program verification and runtime correctness.

### Console Output

These methods provide output via the console.

### Type Constraints

These entities allows constraints between types to be stipulated.

### Aliases

These aliases bring selected immutable types into scope without any imports.

### String Conversions

Conversions to and from String and StringOps.

### Implicit Classes

These implicit classes add useful extension methods to every type.

### CharSequence Conversions

These implicit classes add CharSequence methods to Array[Char] and IndexedSeq[Char] instances.

### Java to Scala

Implicit conversion from Java primitive wrapper types to Scala equivalents.

### Scala to Java

Implicit conversion from Scala AnyVals to Java primitive wrapper types equivalents.

### Array to WrappedArray

Conversions from Arrays to WrappedArrays.

### Ungrouped