1 /*
2  * [The "BSD license"]
3  *  Copyright (c) 2012 Terence Parr
4  *  Copyright (c) 2012 Sam Harwell
5  *  Copyright (c) 2017 Egbert Voig
6  *  All rights reserved.
7  *
8  *  Redistribution and use in source and binary forms, with or without
9  *  modification, are permitted provided that the following conditions
10  *  are met:
11  *
12  *  1. Redistributions of source code must retain the above copyright
13  *     notice, this list of conditions and the following disclaimer.
14  *  2. Redistributions in binary form must reproduce the above copyright
15  *     notice, this list of conditions and the following disclaimer in the
16  *     documentation and/or other materials provided with the distribution.
17  *  3. The name of the author may not be used to endorse or promote products
18  *     derived from this software without specific prior written permission.
19  *
20  *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  *  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 module antlr.v4.runtime.misc.EqualityComparator;
33 
34 /**
35  * @uml
36  * This interface provides an abstract concept of object equality independent of
37  *  {@link Object#equals} (object equality) and the {@code ==} operator
38  *  (reference equality). It can be used to provide algorithm-specific unordered
39  *  comparisons without requiring changes to the object itself.
40  *
41  * @author Sam Harwell
42  */
43 interface EqualityComparator(T)
44 {
45 
46     /**
47      * @uml
48      * This method returns a hash code for the object.
49      * @safe
50      * @nothrow
51      */
52     public static size_t hashOf(T o) @safe nothrow;
53 
54     public static bool opEquals(T a, T b);
55 
56 }