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
|
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/**
* WeakMapMap is a weakmap collection dual-keyed using an object and a string.
* This is useful for keeping data compartmentalized e.g. grouped by tab.
*
* It's name comes from the internal structure which maps a WeakMap to a map,
* which contains the target data.
*
* Usage:
* const myWeakMapMap = new WeakMapMap();
* const key = { randomObject: true };
* myWeakMapMap.set(key, "text1", "Some value1");
* myWeakMapMap.set(key, "text2", "Some value2");
* myWeakMapMap.get(key, "text1"); // Returns "Some value1"
* myWeakMapMap.get(key, "text2"); // Returns "Some value2"
* myWeakMapMap.has(key, "text1"); // Returns true
* myWeakMapMap.has(key, "notakey"); // Returns false
*/
"use strict";
class WeakMapMap {
constructor() {
this.clear();
}
/**
* Returns the value associated to the key and nestedKey, or undefined if
* there is none.
*
* @param {Object} key
* The key associated with the desired value.
* @param {String} nestedKey
* The nested key associated with the desired value.
*/
get(key, nestedKey) {
if (!this.has(key, nestedKey)) {
return undefined;
}
return this.store.get(key).get(nestedKey);
}
/**
* Returns the value associated to the key and nestedKey, or undefined if
* there is none.
*
* @param {Object} key
* The key associated with the desired value.
* @param {String} nestedKey
* The nested key associated with the desired value.
*/
has(key, nestedKey) {
const hasKey = this.store.has(key);
return hasKey && this.store.get(key).has(nestedKey);
}
/**
*
* @param {Object} key
* The key associated with the value.
* @param {String} nestedKey
* The nested key associated with the value.
* @param {any} value
* The value to add.
*/
set(key, nestedKey, value) {
if (!this.store.has(key)) {
this.store.set(key, new Map());
}
const innerMap = this.store.get(key);
innerMap.set(nestedKey, value);
}
/**
* Removes the value associated to the key and nestedKey.
*
* @param {Object} key
* The key associated with the desired value.
* @param {String} nestedKey
* The nested key associated with the desired value.
*
* @returns True if an element in the store has been removed successfully.
* False if the key is not found in the store.
*/
delete(key, nestedKey) {
if (!this.store.has(key)) {
return false;
}
return this.store.get(key).delete(nestedKey);
}
/**
* Clear the store.
*/
clear() {
this.store = new WeakMap();
}
}
module.exports = WeakMapMap;
|
