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>

Platform and version requirements: JVM

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

Platform and version requirements: JS

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