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Kotlin multiplatform port of ANTLR

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/*
 * Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
 * Use of this file is governed by the BSD 3-clause license that
 * can be found in the LICENSE.txt file in the project root.
 */
package org.antlr.v4.kotlinruntime.misc

/**
 * This interface provides an abstract concept of object equality independent of
 * [Object.equals] (object equality) and the `==` operator
 * (reference equality). It can be used to provide algorithm-specific unordered
 * comparisons without requiring changes to the object itself.
 *
 * @author Sam Harwell
 */
interface EqualityComparator {

    /**
     * This method returns a hash code for the specified object.
     *
     * @param obj The object.
     * @return The hash code for `obj`.
     */
    fun hashCode(obj: T): Int

    /**
     * This method tests if two objects are equal.
     *
     * @param a The first object to compare.
     * @param b The second object to compare.
     * @return `true` if `a` equals `b`, otherwise `false`.
     */
    fun equals(a: T?, b: T?): Boolean

}