OptionOrdering
Attributes
- Source
- Ordering.scala
- Graph
-
- Supertypes
Members list
Type members
Inherited classlikes
This inner class defines comparison operators available for T
.
This inner class defines comparison operators available for T
.
It can't extend AnyVal
because it is not a top-level class or a member of a statically accessible object.
Attributes
- Inherited from:
- Ordering
- Source
- Ordering.scala
- Supertypes
Value members
Abstract methods
Attributes
- Source
- Ordering.scala
Concrete methods
Returns an integer whose sign communicates how x compares to y.
Returns an integer whose sign communicates how x compares to y.
The result sign has the following meaning:
- negative if x < y - positive if x > y - zero otherwise (if x == y)
Attributes
- Source
- Ordering.scala
Compares the receiver object (this
) with the argument object (that
) for equivalence.
Compares the receiver object (this
) with the argument object (that
) for equivalence.
Any implementation of this method should be an equivalence relation:
- It is reflexive: for any instance x
of type Any
, x.equals(x)
should return true
. - It is symmetric: for any instances x
and y
of type Any
, x.equals(y)
should return true
if and only if y.equals(x)
returns true
. - It is transitive: for any instances x
, y
, and z
of type Any
if x.equals(y)
returns true
and y.equals(z)
returns true
, then x.equals(z)
should return true
.
If you override this method, you should verify that your implementation remains an equivalence relation. Additionally, when overriding this method it is usually necessary to override hashCode
to ensure that objects which are "equal" (o1.equals(o2)
returns true
) hash to the same scala.Int. (o1.hashCode.equals(o2.hashCode)
).
Value parameters
- that
-
the object to compare against this object for equality.
Attributes
- Returns
-
true
if the receiver object is equivalent to the argument;false
otherwise. - Definition Classes
-
Comparator -> Any
- Source
- Ordering.scala
Calculates a hash code value for the object.
Calculates 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.
Attributes
- Returns
-
the hash code value for this object.
- Definition Classes
- Source
- Ordering.scala
Inherited methods
Return true if x
== y
in the ordering.
Return true if x
== y
in the ordering.
Attributes
- Definition Classes
- Inherited from:
- Ordering
- Source
- Ordering.scala
Return true if x
> y
in the ordering.
Return true if x
> y
in the ordering.
Attributes
- Definition Classes
- Inherited from:
- Ordering
- Source
- Ordering.scala
Return true if x
>= y
in the ordering.
Return true if x
>= y
in the ordering.
Attributes
- Definition Classes
- Inherited from:
- Ordering
- Source
- Ordering.scala
Returns whether or not the other ordering is the opposite ordering of this one.
Returns whether or not the other ordering is the opposite ordering of this one.
Equivalent to other == this.reverse
.
Implementations should only override this method if they are overriding reverse as well.
Attributes
- Inherited from:
- Ordering
- Source
- Ordering.scala
Return true if x
< y
in the ordering.
Return true if x
< y
in the ordering.
Attributes
- Definition Classes
- Inherited from:
- Ordering
- Source
- Ordering.scala
Return true if x
<= y
in the ordering.
Return true if x
<= y
in the ordering.
Attributes
- Definition Classes
- Inherited from:
- Ordering
- Source
- Ordering.scala
Return x
if x
>= y
, otherwise y
.
Return x
if x
<= y
, otherwise y
.
Given f, a function from U into T, creates an Ordering[U] whose compare function is equivalent to:
Given f, a function from U into T, creates an Ordering[U] whose compare function is equivalent to:
def compare(x:U, y:U) = Ordering[T].compare(f(x), f(y))
Attributes
- Inherited from:
- Ordering
- Source
- Ordering.scala
Creates an Ordering[T] whose compare function returns the result of this Ordering's compare function, if it is non-zero, or else the result of other
s compare function.
Creates an Ordering[T] whose compare function returns the result of this Ordering's compare function, if it is non-zero, or else the result of other
s compare function.
Value parameters
- other
-
an Ordering to use if this Ordering returns zero
Attributes
- Example
-
case class Pair(a: Int, b: Int) val pairOrdering = Ordering.by[Pair, Int](_.a) .orElse(Ordering.by[Pair, Int](_.b))
- Inherited from:
- Ordering
- Source
- Ordering.scala
Given f, a function from T into S, creates an Ordering[T] whose compare function returns the result of this Ordering's compare function, if it is non-zero, or else a result equivalent to:
Given f, a function from T into S, creates an Ordering[T] whose compare function returns the result of this Ordering's compare function, if it is non-zero, or else a result equivalent to:
Ordering[S].compare(f(x), f(y))
This function is equivalent to passing the result of Ordering.by(f)
to orElse
.
Attributes
- Example
-
case class Pair(a: Int, b: Int) val pairOrdering = Ordering.by[Pair, Int](_.a) .orElseBy[Int](_.b)
- Inherited from:
- Ordering
- Source
- Ordering.scala
Return the opposite ordering of this one.
Return the opposite ordering of this one.
Implementations overriding this method MUST override isReverseOf as well if they change the behavior at all (for example, caching does not require overriding it).
Attributes
- Definition Classes
- Inherited from:
- Ordering
- Source
- Ordering.scala
Attributes
- Inherited from:
- Comparator
Attributes
- Inherited from:
- Comparator
Attributes
- Inherited from:
- Comparator
Attributes
- Inherited from:
- Comparator
Attributes
- Inherited from:
- Comparator
Attributes
- Inherited from:
- Comparator
Attributes
- Inherited from:
- Comparator
Returns whether a comparison between x
and y
is defined, and if so the result of compare(x, y)
.
Returns whether a comparison between x
and y
is defined, and if so the result of compare(x, y)
.
Attributes
- Inherited from:
- Ordering
- Source
- Ordering.scala
Implicits
Inherited implicits
This implicit method augments T
with the comparison operators defined in scala.math.Ordering.Ops
.
This implicit method augments T
with the comparison operators defined in scala.math.Ordering.Ops
.
Attributes
- Inherited from:
- Ordering
- Source
- Ordering.scala