Package-level declarations

Helper functions for creating java.util.Comparator instances.

Helper functions for creating Comparator instances.

Functions

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.

Since Kotlin 1.1

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.

Since Kotlin 1.1

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.

Since Kotlin 1.1

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

Since Kotlin 1.0

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.

Since Kotlin 1.0

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.

Since Kotlin 1.0

compareByDescending

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.

Since Kotlin 1.1

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.

Since Kotlin 1.1

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.

Since Kotlin 1.0

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.

Since Kotlin 1.0

compareValues

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

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

Since Kotlin 1.1

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

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

Since Kotlin 1.0

compareValuesBy

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.

Since Kotlin 1.1

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.

Since Kotlin 1.1

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.

Since Kotlin 1.1

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

Since Kotlin 1.0

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

Since Kotlin 1.0

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

Since Kotlin 1.0

maxOf

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

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

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

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

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

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

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

Returns the greater of two values.

Since Kotlin 1.1

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

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

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

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

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

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

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

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

Returns the greater of three values.

Since Kotlin 1.1

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

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

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

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

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

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

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

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

Returns the smaller of two values.

Since Kotlin 1.1

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

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

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

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

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

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

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

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

Returns the smaller of three values.

Since Kotlin 1.1

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

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

Returns a comparator that compares Comparable objects in natural order.

Since Kotlin 1.1

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

Returns a comparator that compares Comparable objects in natural order.

Since Kotlin 1.0

nullsFirst

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

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

Since Kotlin 1.1

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.

Since Kotlin 1.1

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

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

Since Kotlin 1.0

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.

Since Kotlin 1.0

nullsLast

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

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

Since Kotlin 1.1

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.

Since Kotlin 1.1

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

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

Since Kotlin 1.0

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.

Since Kotlin 1.0

reversed

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

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

Since Kotlin 1.1

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

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

Since Kotlin 1.0

reverseOrder

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

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

Since Kotlin 1.1

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

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

Since Kotlin 1.0

then

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.

Since Kotlin 1.1

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.

Since Kotlin 1.0

thenBy

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.

Since Kotlin 1.1

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.

Since Kotlin 1.1

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.

Since Kotlin 1.0

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.

Since Kotlin 1.0

thenByDescending

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.

Since Kotlin 1.1

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.

Since Kotlin 1.1

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.

Since Kotlin 1.0

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.

Since Kotlin 1.0

thenComparator

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

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

Since Kotlin 1.1

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

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

Since Kotlin 1.0

thenDescending

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.

Since Kotlin 1.1

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.

Since Kotlin 1.0

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