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Matt McKegg / mutant



Tree: cbf829de3c92ce641590e320ffd3f2fb07a3cf61

Files: cbf829de3c92ce641590e320ffd3f2fb07a3cf61 / set.js

2342 bytesRaw
1var Value = require('./value')
2
3module.exports = Set
4
5function Set (defaultValues) {
6 var object = []
7 var sources = []
8 var releases = []
9
10 if (defaultValues && defaultValues.length) {
11 defaultValues.forEach(function (valueOrObs) {
12 if (!~sources.indexOf(valueOrObs)) {
13 sources.push(valueOrObs)
14 releases[sources.length - 1] = typeof valueOrObs === 'function'
15 ? valueOrObs(refresh)
16 : null
17 }
18 })
19 update()
20 }
21
22 var observable = Value(object)
23 var broadcast = observable.set
24
25 observable.add = function (valueOrObs) {
26 if (!~sources.indexOf(valueOrObs)) {
27 sources.push(valueOrObs)
28 releases[sources.length - 1] = typeof valueOrObs === 'function'
29 ? valueOrObs(refresh)
30 : null
31 refresh()
32 }
33 }
34
35 observable.clear = function () {
36 releases.forEach(tryInvoke)
37 sources.length = 0
38 releases.length = 0
39 refresh()
40 }
41
42 observable.delete = function (valueOrObs) {
43 var index = sources.indexOf(valueOrObs)
44 if (~index) {
45 sources.splice(index, 1)
46 releases.splice(index, 1).forEach(tryInvoke)
47 refresh()
48 }
49 }
50
51 observable.has = function (valueOrObs) {
52 return !!~object.indexOf(valueOrObs)
53 }
54
55 observable.set = function (values) {
56 sources.length = 0
57 values.forEach(function (value) {
58 sources.push(value)
59 })
60 refresh()
61 }
62
63 observable.get = function (index) {
64 return sources[index]
65 }
66
67 observable.getLength = function () {
68 return sources.length
69 }
70
71 observable.destroy = observable.clear
72
73 return observable
74
75 function refresh () {
76 update()
77 broadcast(object)
78 }
79
80 function update () {
81 var currentValues = object.map(get)
82 var newValues = sources.map(resolve)
83 currentValues.filter(notIncluded, newValues).forEach(removeFrom, object)
84 newValues.filter(notIncluded, currentValues).forEach(addTo, object)
85 }
86}
87
88function get (value) {
89 return value
90}
91
92function resolve (source) {
93 return typeof source === 'function' ? source() : source
94}
95
96function notIncluded (value) {
97 return !~this.indexOf(value)
98}
99
100function removeFrom (item) {
101 var index = this.indexOf(item)
102 if (~index) {
103 this.splice(index, 1)
104 }
105}
106
107function addTo (item) {
108 this.push(item)
109}
110
111function tryInvoke (func) {
112 if (typeof func === 'function') {
113 func()
114 }
115}
116

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