Package kotlin.comparisons

Helper functions for creating java.util.Comparator instances.

Helper functions for creating Comparator instances.

Functions

compareBy

Common

fun <T> compareBy(vararg selectors: (T) -> Comparable<*>?): Comparator<T>

Creates a comparator using the sequence of functions to calculate a result of comparison. The functions are called sequentially, receive the given values a and b and return Comparable objects. As soon as the Comparable instances returned by a function for a and b values do not compare as equal, the result of that comparison is returned from the Comparator.

inline fun <T> compareBy(crossinline selector: (T) -> Comparable<*>?): Comparator<T>

Creates a comparator using the function to transform value to a Comparable instance for comparison.

inline fun <T, K> compareBy(comparator: Comparator<in K>, crossinline selector: (T) -> K): Comparator<T>

Creates a comparator using the selector function to transform values being compared and then applying the specified comparator to compare transformed values.

compareByDescending

Common

inline fun <T> compareByDescending(crossinline selector: (T) -> Comparable<*>?): Comparator<T>

Creates a descending comparator using the function to transform value to a Comparable instance for comparison.

inline fun <T, K> compareByDescending(comparator: Comparator<in K>, crossinline selector: (T) -> K): Comparator<T>

Creates a descending comparator using the selector function to transform values being compared and then applying the specified comparator to compare transformed values.

compareValues

Common

fun <T : Comparable<*>> compareValues(a: T?, b: T?): Int

Compares two nullable Comparable values. Null is considered less than any value.

compareValuesBy

Common

fun <T> compareValuesBy(a: T, b: T, vararg selectors: (T) -> Comparable<*>?): Int

Compares two values using the specified functions selectors to calculate the result of the comparison. The functions are called sequentially, receive the given values a and b and return Comparable objects. As soon as the Comparable instances returned by a function for a and b values do not compare as equal, the result of that comparison is returned.

inline fun <T> compareValuesBy(a: T, b: T, selector: (T) -> Comparable<*>?): Int

Compares two values using the specified selector function to calculate the result of the comparison. The function is applied to the given values a and b and return Comparable objects. The result of comparison of these Comparable instances is returned.

inline fun <T, K> compareValuesBy(a: T, b: T, comparator: Comparator<in K>, selector: (T) -> K): Int

Compares two values using the specified selector function to calculate the result of the comparison. The function is applied to the given values a and b and return objects of type K which are then being compared with the given comparator.

maxOf

fun <T : Comparable<T>> maxOf(a: T, b: T): T

inline fun maxOf(a: Byte, b: Byte): Byte

inline fun maxOf(a: Double, b: Double): Double

inline fun maxOf(a: Float, b: Float): Float

inline fun maxOf(a: Int, b: Int): Int

inline fun maxOf(a: Long, b: Long): Long

inline fun maxOf(a: Short, b: Short): Short

fun <T : Comparable<T>> maxOf(a: T, b: T): T

inline fun maxOf(a: Byte, b: Byte): Byte

inline fun maxOf(a: Double, b: Double): Double

inline fun maxOf(a: Float, b: Float): Float

inline fun maxOf(a: Int, b: Int): Int

inline fun maxOf(a: Long, b: Long): Long

inline fun maxOf(a: Short, b: Short): Short

fun <T : Comparable<T>> maxOf(a: T, b: T): T

inline fun maxOf(a: Byte, b: Byte): Byte

inline fun maxOf(a: Double, b: Double): Double

inline fun maxOf(a: Float, b: Float): Float

inline fun maxOf(a: Int, b: Int): Int

inline fun maxOf(a: Long, b: Long): Long

inline fun maxOf(a: Short, b: Short): Short

fun <T : Comparable<T>> maxOf(a: T, b: T): T

inline fun maxOf(a: Byte, b: Byte): Byte

inline fun maxOf(a: Double, b: Double): Double

inline fun maxOf(a: Float, b: Float): Float

inline fun maxOf(a: Int, b: Int): Int

inline fun maxOf(a: Long, b: Long): Long

inline fun maxOf(a: Short, b: Short): Short

Returns the greater of two values.

Since Kotlin

1.1

fun <T : Comparable<T>> maxOf(a: T, vararg other: T): T

fun maxOf(a: Byte, vararg other: Byte): Byte

fun maxOf(a: Double, vararg other: Double): Double

fun maxOf(a: Float, vararg other: Float): Float

fun maxOf(a: Int, vararg other: Int): Int

fun maxOf(a: Long, vararg other: Long): Long

fun maxOf(a: Short, vararg other: Short): Short

@ExperimentalUnsignedTypes

fun maxOf(a: UByte, vararg other: UByte): UByte

@ExperimentalUnsignedTypes

fun maxOf(a: UInt, vararg other: UInt): UInt

@ExperimentalUnsignedTypes

fun maxOf(a: ULong, vararg other: ULong): ULong

@ExperimentalUnsignedTypes

fun maxOf(a: UShort, vararg other: UShort): UShort

fun <T : Comparable<T>> maxOf(a: T, vararg other: T): T

fun maxOf(a: Byte, vararg other: Byte): Byte

fun maxOf(a: Double, vararg other: Double): Double

fun maxOf(a: Float, vararg other: Float): Float

fun maxOf(a: Int, vararg other: Int): Int

fun maxOf(a: Long, vararg other: Long): Long

fun maxOf(a: Short, vararg other: Short): Short

fun <T : Comparable<T>> maxOf(a: T, vararg other: T): T

fun maxOf(a: Byte, vararg other: Byte): Byte

fun maxOf(a: Double, vararg other: Double): Double

fun maxOf(a: Float, vararg other: Float): Float

fun maxOf(a: Int, vararg other: Int): Int

fun maxOf(a: Long, vararg other: Long): Long

fun maxOf(a: Short, vararg other: Short): Short

fun <T : Comparable<T>> maxOf(a: T, vararg other: T): T

fun maxOf(a: Byte, vararg other: Byte): Byte

fun maxOf(a: Double, vararg other: Double): Double

fun maxOf(a: Float, vararg other: Float): Float

fun maxOf(a: Int, vararg other: Int): Int

fun maxOf(a: Long, vararg other: Long): Long

fun maxOf(a: Short, vararg other: Short): Short

Returns the greater of the given values.

Since Kotlin

1.4

Common

fun maxOf(a: UByte, b: UByte): UByte

fun maxOf(a: UInt, b: UInt): UInt

fun maxOf(a: ULong, b: ULong): ULong

fun maxOf(a: UShort, b: UShort): UShort

Returns the greater of two values.

Since Kotlin

1.5

Common

fun <T> maxOf(a: T, b: T, comparator: Comparator<in T>): T

Returns the greater of two values according to the order specified by the given comparator.

Since Kotlin

1.1

Common

fun <T> maxOf(a: T, vararg other: T, comparator: Comparator<in T>): T

Returns the greater of the given values according to the order specified by the given comparator.

Since Kotlin

1.4

fun <T : Comparable<T>> maxOf(a: T, b: T, c: T): T

inline fun maxOf(a: Byte, b: Byte, c: Byte): Byte

inline fun maxOf(a: Double, b: Double, c: Double): Double

inline fun maxOf(a: Float, b: Float, c: Float): Float

inline fun maxOf(a: Int, b: Int, c: Int): Int

inline fun maxOf(a: Long, b: Long, c: Long): Long

inline fun maxOf(a: Short, b: Short, c: Short): Short

fun <T : Comparable<T>> maxOf(a: T, b: T, c: T): T

inline fun maxOf(a: Byte, b: Byte, c: Byte): Byte

inline fun maxOf(a: Double, b: Double, c: Double): Double

inline fun maxOf(a: Float, b: Float, c: Float): Float

inline fun maxOf(a: Int, b: Int, c: Int): Int

inline fun maxOf(a: Long, b: Long, c: Long): Long

inline fun maxOf(a: Short, b: Short, c: Short): Short

fun <T : Comparable<T>> maxOf(a: T, b: T, c: T): T

inline fun maxOf(a: Byte, b: Byte, c: Byte): Byte

inline fun maxOf(a: Double, b: Double, c: Double): Double

inline fun maxOf(a: Float, b: Float, c: Float): Float

inline fun maxOf(a: Int, b: Int, c: Int): Int

inline fun maxOf(a: Long, b: Long, c: Long): Long

inline fun maxOf(a: Short, b: Short, c: Short): Short

fun <T : Comparable<T>> maxOf(a: T, b: T, c: T): T

inline fun maxOf(a: Byte, b: Byte, c: Byte): Byte

inline fun maxOf(a: Double, b: Double, c: Double): Double

inline fun maxOf(a: Float, b: Float, c: Float): Float

inline fun maxOf(a: Int, b: Int, c: Int): Int

inline fun maxOf(a: Long, b: Long, c: Long): Long

inline fun maxOf(a: Short, b: Short, c: Short): Short

Returns the greater of three values.

Since Kotlin

1.1

Common

inline fun maxOf(a: UByte, b: UByte, c: UByte): UByte

inline fun maxOf(a: UInt, b: UInt, c: UInt): UInt

inline fun maxOf(a: ULong, b: ULong, c: ULong): ULong

inline fun maxOf(a: UShort, b: UShort, c: UShort): UShort

Returns the greater of three values.

Since Kotlin

1.5

Common

fun <T> maxOf(a: T, b: T, c: T, comparator: Comparator<in T>): T

Returns the greater of three values according to the order specified by the given comparator.

Since Kotlin

1.1

minOf

fun <T : Comparable<T>> minOf(a: T, b: T): T

inline fun minOf(a: Byte, b: Byte): Byte

inline fun minOf(a: Double, b: Double): Double

inline fun minOf(a: Float, b: Float): Float

inline fun minOf(a: Int, b: Int): Int

inline fun minOf(a: Long, b: Long): Long

inline fun minOf(a: Short, b: Short): Short

fun <T : Comparable<T>> minOf(a: T, b: T): T

inline fun minOf(a: Byte, b: Byte): Byte

inline fun minOf(a: Double, b: Double): Double

inline fun minOf(a: Float, b: Float): Float

inline fun minOf(a: Int, b: Int): Int

inline fun minOf(a: Long, b: Long): Long

inline fun minOf(a: Short, b: Short): Short

fun <T : Comparable<T>> minOf(a: T, b: T): T

inline fun minOf(a: Byte, b: Byte): Byte

inline fun minOf(a: Double, b: Double): Double

inline fun minOf(a: Float, b: Float): Float

inline fun minOf(a: Int, b: Int): Int

inline fun minOf(a: Long, b: Long): Long

inline fun minOf(a: Short, b: Short): Short

fun <T : Comparable<T>> minOf(a: T, b: T): T

inline fun minOf(a: Byte, b: Byte): Byte

inline fun minOf(a: Double, b: Double): Double

inline fun minOf(a: Float, b: Float): Float

inline fun minOf(a: Int, b: Int): Int

inline fun minOf(a: Long, b: Long): Long

inline fun minOf(a: Short, b: Short): Short

Returns the smaller of two values.

Since Kotlin

1.1

fun <T : Comparable<T>> minOf(a: T, vararg other: T): T

fun minOf(a: Byte, vararg other: Byte): Byte

fun minOf(a: Double, vararg other: Double): Double

fun minOf(a: Float, vararg other: Float): Float

fun minOf(a: Int, vararg other: Int): Int

fun minOf(a: Long, vararg other: Long): Long

fun minOf(a: Short, vararg other: Short): Short

@ExperimentalUnsignedTypes

fun minOf(a: UByte, vararg other: UByte): UByte

@ExperimentalUnsignedTypes

fun minOf(a: UInt, vararg other: UInt): UInt

@ExperimentalUnsignedTypes

fun minOf(a: ULong, vararg other: ULong): ULong

@ExperimentalUnsignedTypes

fun minOf(a: UShort, vararg other: UShort): UShort

fun <T : Comparable<T>> minOf(a: T, vararg other: T): T

fun minOf(a: Byte, vararg other: Byte): Byte

fun minOf(a: Double, vararg other: Double): Double

fun minOf(a: Float, vararg other: Float): Float

fun minOf(a: Int, vararg other: Int): Int

fun minOf(a: Long, vararg other: Long): Long

fun minOf(a: Short, vararg other: Short): Short

fun <T : Comparable<T>> minOf(a: T, vararg other: T): T

fun minOf(a: Byte, vararg other: Byte): Byte

fun minOf(a: Double, vararg other: Double): Double

fun minOf(a: Float, vararg other: Float): Float

fun minOf(a: Int, vararg other: Int): Int

fun minOf(a: Long, vararg other: Long): Long

fun minOf(a: Short, vararg other: Short): Short

fun <T : Comparable<T>> minOf(a: T, vararg other: T): T

fun minOf(a: Byte, vararg other: Byte): Byte

fun minOf(a: Double, vararg other: Double): Double

fun minOf(a: Float, vararg other: Float): Float

fun minOf(a: Int, vararg other: Int): Int

fun minOf(a: Long, vararg other: Long): Long

fun minOf(a: Short, vararg other: Short): Short

Returns the smaller of the given values.

Since Kotlin

1.4

Common

fun minOf(a: UByte, b: UByte): UByte

fun minOf(a: UInt, b: UInt): UInt

fun minOf(a: ULong, b: ULong): ULong

fun minOf(a: UShort, b: UShort): UShort

Returns the smaller of two values.

Since Kotlin

1.5

Common

fun <T> minOf(a: T, b: T, comparator: Comparator<in T>): T

Returns the smaller of two values according to the order specified by the given comparator.

Since Kotlin

1.1

Common

fun <T> minOf(a: T, vararg other: T, comparator: Comparator<in T>): T

Returns the smaller of the given values according to the order specified by the given comparator.

Since Kotlin

1.4

fun <T : Comparable<T>> minOf(a: T, b: T, c: T): T

inline fun minOf(a: Byte, b: Byte, c: Byte): Byte

inline fun minOf(a: Double, b: Double, c: Double): Double

inline fun minOf(a: Float, b: Float, c: Float): Float

inline fun minOf(a: Int, b: Int, c: Int): Int

inline fun minOf(a: Long, b: Long, c: Long): Long

inline fun minOf(a: Short, b: Short, c: Short): Short

fun <T : Comparable<T>> minOf(a: T, b: T, c: T): T

inline fun minOf(a: Byte, b: Byte, c: Byte): Byte

inline fun minOf(a: Double, b: Double, c: Double): Double

inline fun minOf(a: Float, b: Float, c: Float): Float

inline fun minOf(a: Int, b: Int, c: Int): Int

inline fun minOf(a: Long, b: Long, c: Long): Long

inline fun minOf(a: Short, b: Short, c: Short): Short

fun <T : Comparable<T>> minOf(a: T, b: T, c: T): T

inline fun minOf(a: Byte, b: Byte, c: Byte): Byte

inline fun minOf(a: Double, b: Double, c: Double): Double

inline fun minOf(a: Float, b: Float, c: Float): Float

inline fun minOf(a: Int, b: Int, c: Int): Int

inline fun minOf(a: Long, b: Long, c: Long): Long

inline fun minOf(a: Short, b: Short, c: Short): Short

fun <T : Comparable<T>> minOf(a: T, b: T, c: T): T

inline fun minOf(a: Byte, b: Byte, c: Byte): Byte

inline fun minOf(a: Double, b: Double, c: Double): Double

inline fun minOf(a: Float, b: Float, c: Float): Float

inline fun minOf(a: Int, b: Int, c: Int): Int

inline fun minOf(a: Long, b: Long, c: Long): Long

inline fun minOf(a: Short, b: Short, c: Short): Short

Returns the smaller of three values.

Since Kotlin

1.1

Common

inline fun minOf(a: UByte, b: UByte, c: UByte): UByte

inline fun minOf(a: UInt, b: UInt, c: UInt): UInt

inline fun minOf(a: ULong, b: ULong, c: ULong): ULong

inline fun minOf(a: UShort, b: UShort, c: UShort): UShort

Returns the smaller of three values.

Since Kotlin

1.5

Common

fun <T> minOf(a: T, b: T, c: T, comparator: Comparator<in T>): T

Returns the smaller of three values according to the order specified by the given comparator.

Since Kotlin

1.1

naturalOrder

Common

fun <T : Comparable<T>> naturalOrder(): Comparator<T>

Returns a comparator that compares Comparable objects in natural order.

nullsFirst

Common

inline fun <T : Comparable<T>> nullsFirst(): Comparator<T?>

Provides a comparator of nullable Comparable values considering null value less than any other value.

fun <T : Any> nullsFirst(comparator: Comparator<in T>): Comparator<T?>

Extends the given comparator of non-nullable values to a comparator of nullable values considering null value less than any other value.

nullsLast

Common

inline fun <T : Comparable<T>> nullsLast(): Comparator<T?>

Provides a comparator of nullable Comparable values considering null value greater than any other value.

fun <T : Any> nullsLast(comparator: Comparator<in T>): Comparator<T?>

Extends the given comparator of non-nullable values to a comparator of nullable values considering null value greater than any other value.

reversed

Common

fun <T> Comparator<T>.reversed(): Comparator<T>

Returns a comparator that imposes the reverse ordering of this comparator.

reverseOrder

Common

fun <T : Comparable<T>> reverseOrder(): Comparator<T>

Returns a comparator that compares Comparable objects in reversed natural order.

then

Common

infix fun <T> Comparator<T>.then(comparator: Comparator<in T>): Comparator<T>

Combines this comparator and the given comparator such that the latter is applied only when the former considered values equal.

thenBy

Common

inline fun <T> Comparator<T>.thenBy(crossinline selector: (T) -> Comparable<*>?): Comparator<T>

Creates a comparator comparing values after the primary comparator defined them equal. It uses the function to transform value to a Comparable instance for comparison.

inline fun <T, K> Comparator<T>.thenBy(comparator: Comparator<in K>, crossinline selector: (T) -> K): Comparator<T>

Creates a comparator comparing values after the primary comparator defined them equal. It uses the selector function to transform values and then compares them with the given comparator.

thenByDescending

Common

inline fun <T> Comparator<T>.thenByDescending(crossinline selector: (T) -> Comparable<*>?): Comparator<T>

Creates a descending comparator using the primary comparator and the function to transform value to a Comparable instance for comparison.

inline fun <T, K> Comparator<T>.thenByDescending(comparator: Comparator<in K>, crossinline selector: (T) -> K): Comparator<T>

Creates a descending comparator comparing values after the primary comparator defined them equal. It uses the selector function to transform values and then compares them with the given comparator.

thenComparator

Common

inline fun <T> Comparator<T>.thenComparator(crossinline comparison: (T, T) -> Int): Comparator<T>

Creates a comparator using the primary comparator and function to calculate a result of comparison.

thenDescending

Common

infix fun <T> Comparator<T>.thenDescending(comparator: Comparator<in T>): Comparator<T>

Combines this comparator and the given comparator such that the latter is applied only when the former considered values equal.