/* __ *\ ** ________ ___ / / ___ Scala API ** ** / __/ __// _ | / / / _ | (c) 2003-2013, LAMP/EPFL ** ** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ ** ** /____/\___/_/ |_/____/_/ | | ** ** |/ ** \* */ package scala package util.hashing import scala.annotation.implicitNotFound /** `Hashing` is a trait whose instances each represent a strategy for hashing * instances of a type. * * `Hashing`'s companion object defines a default hashing strategy for all * objects - it calls their `##` method. * * Note: when using a custom `Hashing`, make sure to use it with the `Equiv` * such that if any two objects are equal, then their hash codes must be equal. * * @since 2.10 */ @implicitNotFound(msg = "No implicit Hashing defined for ${T}.") trait Hashing[T] extends Serializable { def hash(x: T): Int } object Hashing { final class Default[T] extends Hashing[T] { def hash(x: T) = x.## } implicit def default[T] = new Default[T] def fromFunction[T](f: T => Int) = new Hashing[T] { def hash(x: T) = f(x) } }