abstract final class Boolean extends AnyVal
Boolean
(equivalent to Java's boolean
primitive type) is a
subtype of scala.AnyVal. Instances of Boolean
are not
represented by an object in the underlying runtime system.
There is an implicit conversion from scala.Boolean => scala.runtime.RichBoolean which provides useful non-primitive operations.
- Source
- Boolean.scala
- Alphabetic
- By Inheritance
- Boolean
- AnyVal
- Any
- by boolean2Boolean
- by booleanWrapper
- by any2stringadd
- by StringFormat
- by Ensuring
- by ArrowAssoc
- Hide All
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- Public
- All
Abstract Value Members
-
abstract
def
!=(x: Boolean): Boolean
Compares two Boolean expressions and returns
true
if they evaluate to a different value.Compares two Boolean expressions and returns
true
if they evaluate to a different value.a != b
returnstrue
if and only ifa
istrue
andb
isfalse
ora
isfalse
andb
istrue
.
-
abstract
def
&(x: Boolean): Boolean
Compares two Boolean expressions and returns
true
if both of them evaluate to true.Compares two Boolean expressions and returns
true
if both of them evaluate to true.a & b
returnstrue
if and only ifa
andb
aretrue
.
- Note
This method evaluates both
a
andb
, even if the result is already determined after evaluatinga
.
-
abstract
def
&&(x: Boolean): Boolean
Compares two Boolean expressions and returns
true
if both of them evaluate to true.Compares two Boolean expressions and returns
true
if both of them evaluate to true.a && b
returnstrue
if and only ifa
andb
aretrue
.
- Note
This method uses 'short-circuit' evaluation and behaves as if it was declared as
def &&(x: => Boolean): Boolean
. Ifa
evaluates tofalse
,false
is returned without evaluatingb
.
-
abstract
def
==(x: Boolean): Boolean
Compares two Boolean expressions and returns
true
if they evaluate to the same value.Compares two Boolean expressions and returns
true
if they evaluate to the same value.a == b
returnstrue
if and only ifa
andb
aretrue
ora
andb
arefalse
.
-
abstract
def
^(x: Boolean): Boolean
Compares two Boolean expressions and returns
true
if they evaluate to a different value.Compares two Boolean expressions and returns
true
if they evaluate to a different value.a ^ b
returns
trueif and only if
a
istrue
andb
isfalse
ora
isfalse
andb
istrue
.
-
abstract
def
unary_!: Boolean
Negates a Boolean expression.
Negates a Boolean expression.
-
!a
results infalse
if and only ifa
evaluates totrue
and -!a
results intrue
if and only ifa
evaluates tofalse
.- returns
the negated expression
-
abstract
def
|(x: Boolean): Boolean
Compares two Boolean expressions and returns
true
if one or both of them evaluate to true.Compares two Boolean expressions and returns
true
if one or both of them evaluate to true.a | b
returnstrue
if and only ifa
istrue
orb
istrue
ora
andb
aretrue
.
- Note
This method evaluates both
a
andb
, even if the result is already determined after evaluatinga
.
-
abstract
def
||(x: Boolean): Boolean
Compares two Boolean expressions and returns
true
if one or both of them evaluate to true.Compares two Boolean expressions and returns
true
if one or both of them evaluate to true.a || b
returnstrue
if and only ifa
istrue
orb
istrue
ora
andb
aretrue
.
- Note
This method uses 'short-circuit' evaluation and behaves as if it was declared as
def ||(x: => Boolean): Boolean
. Ifa
evaluates totrue
,true
is returned without evaluatingb
.
Concrete Value Members
-
def
<(that: Boolean): Boolean
Returns true if
this
is less thanthat
Returns true if
this
is less thanthat
- Implicit
- This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
- Definition Classes
- Ordered
-
def
<=(that: Boolean): Boolean
Returns true if
this
is less than or equal tothat
.Returns true if
this
is less than or equal tothat
.- Implicit
- This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
- Definition Classes
- Ordered
-
def
>(that: Boolean): Boolean
Returns true if
this
is greater thanthat
.Returns true if
this
is greater thanthat
.- Implicit
- This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
- Definition Classes
- Ordered
-
def
>=(that: Boolean): Boolean
Returns true if
this
is greater than or equal tothat
.Returns true if
this
is greater than or equal tothat
.- Implicit
- This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
- Definition Classes
- Ordered
-
def
booleanValue(): Boolean
- Implicit
- This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
- Definition Classes
- Boolean
-
def
compare(y: Boolean): Int
Result of comparing
this
with operandthat
.Result of comparing
this
with operandthat
.Implement this method to determine how instances of A will be sorted.
Returns
x
where:x < 0
whenthis < that
x == 0
whenthis == that
x > 0
whenthis > that
- Implicit
- This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
- Definition Classes
- OrderedProxy → Ordered
-
def
compareTo(arg0: java.lang.Boolean): Int
- Implicit
- This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
- Definition Classes
- Boolean → Comparable
-
def
compareTo(that: Boolean): Int
Result of comparing
this
with operandthat
.Result of comparing
this
with operandthat
.- Implicit
- This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
- Definition Classes
- Ordered → Comparable
-
def
getClass(): Class[Boolean]
Returns the runtime class representation of the object.
-
val
self: Boolean
- Implicit
- This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
- Definition Classes
- RichBoolean → Typed → Proxy
Shadowed Implicit Value Members
-
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.
- Implicit
- This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:(boolean: java.lang.Boolean).equals(arg0)
- Definition Classes
- Boolean → AnyRef → Any
-
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.
- Implicit
- This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:(boolean: java.lang.Boolean).hashCode()
- Definition Classes
- Boolean → AnyRef → Any
-
def
toString(): 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.
- Implicit
- This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:(boolean: java.lang.Boolean).toString()
- Definition Classes
- Boolean → AnyRef → Any
-
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.
- Implicit
- This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:(boolean: RichBoolean).toString()
- Definition Classes
- Proxy → Any
This is the documentation for the Scala standard library.
Package structure
The scala package contains core types like
Int
,Float
,Array
orOption
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 frameworkscala.collection.immutable
- Immutable, sequential data-structures such asVector
,List
,Range
,HashMap
orHashSet
scala.collection.mutable
- Mutable, sequential data-structures such asArrayBuffer
,StringBuilder
,HashMap
orHashSet
scala.collection.concurrent
- Mutable, concurrent data-structures such asTrieMap
scala.collection.parallel.immutable
- Immutable, parallel data-structures such asParVector
,ParRange
,ParHashMap
orParHashSet
scala.collection.parallel.mutable
- Mutable, parallel data-structures such asParArray
,ParHashMap
,ParTrieMap
orParHashSet
scala.concurrent
- Primitives for concurrent programming such asFutures
andPromises
scala.io
- Input and output operationsscala.math
- Basic math functions and additional numeric types likeBigInt
andBigDecimal
scala.sys
- Interaction with other processes and the operating systemscala.util.matching
- Regular expressionsOther 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 forscala.collection.immutable.List
.Other aliases refer to classes provided by the underlying platform. For example, on the JVM,
String
is an alias forjava.lang.String
.