1
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var wrappy = require('wrappy')
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2
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module.exports = wrappy(once)
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3
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module.exports.strict = wrappy(onceStrict)
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4
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5
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once.proto = once(function () {
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6
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Object.defineProperty(Function.prototype, 'once', {
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7
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value: function () {
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8
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return once(this)
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9
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},
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10
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configurable: true
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11
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})
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12
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|
13
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Object.defineProperty(Function.prototype, 'onceStrict', {
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14
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value: function () {
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15
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return onceStrict(this)
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16
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},
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17
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configurable: true
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18
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})
|
19
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})
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20
|
|
21
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function once (fn) {
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22
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var f = function () {
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23
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if (f.called) return f.value
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24
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f.called = true
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25
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return f.value = fn.apply(this, arguments)
|
26
|
}
|
27
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f.called = false
|
28
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return f
|
29
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}
|
30
|
|
31
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function onceStrict (fn) {
|
32
|
var f = function () {
|
33
|
if (f.called)
|
34
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throw new Error(f.onceError)
|
35
|
f.called = true
|
36
|
return f.value = fn.apply(this, arguments)
|
37
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}
|
38
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var name = fn.name || 'Function wrapped with `once`'
|
39
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f.onceError = name + " shouldn't be called more than once"
|
40
|
f.called = false
|
41
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return f
|
42
|
}
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