-
Notifications
You must be signed in to change notification settings - Fork 0
/
Hashable.ts
167 lines (141 loc) · 3.9 KB
/
Hashable.ts
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
import { isPersistent, isImmutable } from './Persistent';
import { PCGRandom, isDefined, isPlain, isIterable } from '@frptools/corelib';
export interface Hashable {
'@@hash' (): number;
}
export function isHashable (value: object): value is Hashable;
export function isHashable (value: object): boolean;
export function isHashable (value: object): value is Hashable {
return '@@hash' in <any>value;
}
export function hash (arg: any): number {
return opt(_hash(arg));
}
export function hashArray (arr: any[]): number {
return opt(_hashArray(arr));
}
export function hashArgs (...args: any[]): number;
export function hashArgs (): number {
var h = 5381;
for (var i = 0; i < arguments.length; i++) {
h = _combineHash(h, hash(arguments[i]));
}
return opt(h);
}
export function combineHash (a: number, b: number): number {
return opt(_combineHash(a, b));
}
export function hashObject (value: object): number {
return opt(_hashObject(value));
}
export function hashMiscRef (o: Object): number {
return opt(_hashMiscRef(o));
}
export function hashIterator (it: Iterator<any>): number {
return opt(_hashIterator(it));
}
export function hashPlainObject (o: object): number {
return opt(_hashPlainObject(o));
}
export function hashNumber (n: number): number {
return opt(_hashNumber(n));
}
export function hashString (str: string): number {
return opt(_hashString(str));
}
function isZero (value: any): boolean {
return value === null || value === void 0 || value === false;
}
const RANDOM = new PCGRandom(13);
const CACHE = new WeakMap<Object, number>();
function randomInt () {
return RANDOM.integer(0x7FFFFFFF);
}
function _hash (arg: any): number {
if (isZero(arg)) return 0;
if (typeof arg.valueOf === 'function' && arg.valueOf !== Object.prototype.valueOf) {
arg = arg.valueOf();
if (isZero(arg)) return 0;
}
switch (typeof arg) {
case 'number': return _hashNumber(arg);
case 'string': return _hashString(arg);
case 'function': return _hashMiscRef(arg);
case 'object': return _hashObject(arg);
case 'boolean': return arg === true ? 1 : 0;
default: return 0;
}
}
function _hashArray (arr: any[]): number {
var h = 6151;
for (var i = 0; i < arr.length; i++) {
h ^= _combineHash(_hashNumber(i), _hash(arr[i]));
}
return h;
}
function _combineHash (a: number, b: number): number {
return (a * 53) ^ b;
}
function _hashObject (value: object): number {
var h = CACHE.get(value);
if (isDefined(h)) return h;
if (Array.isArray(value)) {
h = _hashArray(value);
}
else if (isHashable(value)) {
h = value['@@hash']();
}
else if (isIterable(value)) {
h = _hashIterator(value[Symbol.iterator]());
}
else if (isPlain(value)) {
h = _hashPlainObject(value);
}
else {
h = randomInt();
}
if (!isPersistent(value) || isImmutable(value)) {
CACHE.set(value, h);
}
return h;
}
function _hashMiscRef (o: Object): number {
var h = CACHE.get(o);
if (isDefined(h)) return h;
h = randomInt();
CACHE.set(o, h);
return h;
}
function _hashIterator (it: Iterator<any>): number {
var h = 6151;
var current: IteratorResult<any>;
while (!(current = it.next()).done) {
h = _combineHash(h, hash(current.value));
}
return h;
}
function _hashPlainObject (o: object): number {
CACHE.set(o, randomInt());
var keys = Object.keys(o);
var h = 12289;
for (var i = 0; i < keys.length; i++) {
h = _combineHash(h, _hashString(keys[i]));
h = _combineHash(h, hash((o as any)[keys[i]]));
}
return h;
}
function _hashNumber (n: number): number {
if (n !== n || n === Infinity) return 0;
var h = n | 0;
if (h !== n) h ^= n * 0xFFFFFFFF;
while (n > 0xFFFFFFFF) h ^= (n /= 0xFFFFFFFF);
return n;
}
function _hashString (str: string): number {
var h = 5381, i = str.length;
while (i) h = (h * 33) ^ str.charCodeAt(--i);
return h;
}
function opt (n: number) {
return (n & 0xbfffffff) | ((n >>> 1) & 0x40000000);
}